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Message started by Steve Deckert on 07/01/19 at 02:00:15

Title: Steve's BIG BETSY Project
Post by Steve Deckert on 07/01/19 at 02:00:15


Inspired by Caintuck Audio's Randy Rash and his stunning Betsy Open-Baffle design, I decided my first truly serious project in my new wood shop would be to build a giant pair of Betsy Open Baffle loudspeakers.

https://www.decware.com/newsite/Caintuck.html

I simply scaled Randy's design up for a 15 inch driver, with the intension of using these as bass baffles to further enhance the Betsy Open-Baffle sound that I love so much!  I had a strong feeling that if I did this, I would likely have a new reference pair of speakers that I liked better than my current selection, specifically the DNA2 and the HR1 speakers which I consider the best full-range offerings we have.  If I could do that, it would be really something.

Here is my plans.  I realize these plans will short out a lot of DIY speaker builders who like in-depth plans, but for myself, this is all I ever do... it has all the information I need to build the loudspeaker.  The cut out diameter will be determined by the actual diameter of the drivers I decide to use.

They basically end up being around twice as tall, twice as wide and twice as thick.  Shouldn't be a big deal right... only twice as big!

Actually not so.  The original size Betsy consumes around 6 or 7 board feet per speaker.  So does the big one use 12 or 14 board feet?  No, it took 36+ board feet. So to say they are twice as big would be somewhat misleading.

Anyway, this is where it all started.  I am matching a solid Paduke and Wenge baffle to exactly match the pair of Betsys from Randy at Caintuck Audio.




Here is a picture of my personal pair of Caintuck Audio's Betsy Baffles, done solid hardwood and outfitted with the Alnico drivers.  This is what I intend to exactly reproduce at the larger scale drawn above.


 
Steve







Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/01/19 at 03:08:31



Before I get into the build... a note about the shop. Built under some decaying ash trees I decided to make it with a 12 pitch roof. Not only that, but with everything at 16 inches on center and 100% screwed together. The roof is super strong. The pitch is so steep and so frikin high that I almost pissed my pants at least 50 times framing it.  

Last night I got to see it in action, as a huge tree fell splitting two other trees all onto the roof of my new shop.  Slid right off like rain.  No structural damage.  The shed behind the shop was smashed.




Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/01/19 at 03:19:06




The shed behind the shop.


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/01/19 at 03:53:01


I purchased 20 BF of African Paduke and 20 BF of Wenge. The Wenge delivered is $22 a board foot. The Paduke is about half that. Nevertheless the total cost of materials gave me real pause. I had to think about it for a couple of days knowing I could probably make the same thing out of plywood with veneer for a fraction of the amount. To get myself over the hump I simply calculated the materials wrong and purchased less than I'll actually needed.  

Whoops.



Before it was over another 18 BF of wedge was needed, and 20BF of oak.  ::)

In this picture I have run the Paduke through the jointer and planer as well as two of the Wenge boards.

Interesting note... hating to waste an 1/8 inch for each cut on the table saw, I ran the Paduke through my band saw and it cut it like butter with precious little waste.  When it came time to do the Wenge, which I was already short on I knew I was going to do the same thing.  However, when applying the Wenge to the bandsaw, the bandsaw dropped its first F-Bomb and proceeded to cut the opposite of a straight line.  Wenge is really unbelievably hard and heavy wood.  A single one of those black boards you see in the picture probably weighs 30 lbs!

Haha, looking back on it, I would have to be a real wood craftsman or desperate for money to build a pair of these with this much Wenge.  Of course ignorance is bliss until you reach that moment where you wonder what you have just gotten yourself into!

Somehow we have to make two giant Betsy baffles out of these boards.

-Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/01/19 at 04:19:41


Here is some of the Paduke. I've machined the first three boards which is setting the thickness for the entire project. That turned out be 1.74 inches in the end, however in this picture it was closer to 1.85. After I had every single board machined in both Paduke and Wenge I ran everything through a final polishing pass because I assumed that is what my wood guru Bob Zigler would have done : )



BTW, I found out what my planer was actually capable of doing when I ran a tapered 8 inch wide 2 inch board 4 feet long through it and by the end it was at a full  1/8 inch cut. While the bandsaw dropped and F-Bomb on the Wenge, the Planer just dug-in and got the job done to my complete astonishment. This was a holy-crap moment that still has me shaking my head!  If you drop a 2 inch solid Paduke board on you foot you're going to anciently drop an F-Bomb yourself... but if you drop the same size Wenge board on your foot, you're going to the hospital.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/01/19 at 04:31:23


Here is all the boards machined square and to the same thickness.  




Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/01/19 at 04:37:48


Now the brain melter for amateur wood workers like myself... figuring out how to stretch the wood you have after machining to get the job done without buying more!



Clearly I have not enough to create a full rectangular panel, so I have to figure out a way to get the missing wood to land in the center of what would be the cut-out for the woofer!

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/01/19 at 04:41:20


After a few days I came up with this...



As if it wasn't stressful enough trying to stretch the wood (at $22 a BF) HALF of the Wenge was 1/4 sawn, and half was not.  Now, Wenge that is not quarter sawn looks like frikin black and yellow plywood.  It's hateful looking so now two of my 8 inch x 48 inch boards had to be cut into 1.74 inch strips and rotated 90 degrees to and glued back together to create the illusion of a quarter sawn board.


Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/01/19 at 04:45:27


Here is another view of how I joined the boards into panels with what I had. Getting the jointer at a perfect 90 so I can flip the boards at will was easier said than done, also I glued and clamped one joint at a time so I didn't get surprised when it was all done with a curved panel.  That's why it took so long.



Of course by now we're on week two, and a plywood or MDF model would have been a two day gig to get to this point.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/01/19 at 04:51:46


The next big thrill is to try to cut the arc perfectly...  the bandsaw option is out, panel is too heavy to lift.  We all know the only way is the dreadful router.  This is too serious for a mid-fi router, so I had to remove the PC from my router table and make a jig big enough to swing the arc.  

Interesting note:  The radius of the arc will end up being the same length as the height... around 42 inches.  Sacred geometry at work here...



It took a carbide spiral SATAN bit to make this cut.  It's a SATAN bit because if you run it too slow it will worm it's way at mach 6 through your board and then through side of your building with the router and you attached!  Baddddd asss bit... scares the crap out of me.


Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/01/19 at 04:58:07


Here is another view of the first cut.



Yes it's polished like a mirror... the Satan bit that cost as much as a Chinese router has my complete fear and respect.

To not blow out any of the edge was a real thrill. Problem is I have to do it three more times with equally perfect results. By this time I am realizing that even one mistake anywhere in the rest of this build will be catastrophic. This is really slowing me down at this point. Every move is pondered.

I now have a real understanding for why it takes so long to build perfect cabinets. God Bless you Bob Ziegler!! And You too Randy...  If I can make these monsters look as good as yours, well... that would be my goal since I'm trying to exactly match the pair!

Steve


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/01/19 at 05:06:15



It was a perfect day for it... idillic in fact.  72'F nice breeze, birds chirping, low humidity, no bugs.  Don't worry I appreciated every second of it.  



Both sides of the first panel are done with no flaws.  Trying to do the second one without waiting 24 hours would be certain disaster... can't chance it.  Going too well.

-Steve

Title: Re: Steve's BIG BETSY Project
Post by ZYGI on 07/01/19 at 16:23:08

Steve, they look great!!

Shop looks great as well.

Guys, you don't even want to know how much I cringed to see Steve's old table saw sitting out in the rain with a crustacean of rust on the top. But the dam thing still worked!

Zygi

Title: Re: Steve's BIG BETSY Project
Post by ScottNC on 07/01/19 at 16:43:13

I guess he was done with it!   [smiley=10.gif]

Those slabs of gorgeous wood look incredible, can’t wait to see more of this endeavor.

Best,
Scott

Title: Re: Steve's BIG BETSY Project
Post by Lon on 07/01/19 at 17:01:38

I know from a luthier that wenge is very hard to work with. But it's a great tone wood for instruments--I have it as neck and fingerboard for one guitar and one bass, and they are favorites.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/01/19 at 17:14:58

Tell me more about the router bit. I would assume solid carbide with some sort of coating??

Title: Re: Steve's BIG BETSY Project
Post by Dominick on 07/01/19 at 18:26:20

Steve...The Cathedral wood shop has come a long way since Decfest.  

Glad to hear the tree didn’t take it out.  If I can make to to Decfest again this year....it will be interesting to hear how the room sounds now that it’s closed off.  

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/01/19 at 19:28:07


The shop sounds very respectable.  It would drive me nuts if it didn't.  Absorption on all four walls and the roof.  Bass is wonderful out there.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/01/19 at 19:31:57

Donnie,

Here are the Satan bits I use:  https://www.infinitytools.com/routing/router-bits/carbide/straight-spiral-router-bits/solid-carbide-spiral-router-bits-10847



#85915, the actual bit is the tallest one in the picture... see it's devilish horns?

Steve

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/01/19 at 21:21:27



Wow !!!

Very cool .....

Steve ..... might I suggest that this baffle be named the "Big Bertha" .....

Looking forward to seeing (and hearing) the finished project.

Happy listening,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/01/19 at 22:12:04

That is a kick ass cutter.
If you ever dull it down, take it to Countyline Tool Grinding and have it resharpened, They are right there in E. Peoria, I guarantee you that you have driven past  their shop a thousand times.
You probably can get 2 regrinds out of it to bring the cost of ownership down a bit.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/02/19 at 01:42:55

Here is the tree this evening... still moving slowly towards the ground through my shed.



Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/02/19 at 01:44:42




Basically at this point the fence is holding it up.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/02/19 at 01:52:51


Getting ready to cut the hole for the woofer...






Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/02/19 at 01:54:18


No vacuum hose for this cut...




Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/02/19 at 01:57:33




Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/02/19 at 02:07:54


Fixing the side where on the last cut I blew out a large chunk of Wenge... and then lots of sanding.  Trying to keep everything perfectly flat...



Next will come the linseed oil to seal it up.

Steve


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/02/19 at 02:10:30


Letting it swim in linseed oil for awhile before I wipe it off.



Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/02/19 at 02:12:02


After it was wiped off.  Will get a second coat tomorrow.



This is the back side

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/02/19 at 02:23:24


Next I have to figure out how I want to handle the base that keeps it upright.  I can make a nearly 24 inch base scaled from the original Betsy which is about 12 inches... or change it.  I pondered this for a long time.  Despite the fact that I can not even lift the baffle, when it is on the floor it becomes weightless.  That means precious little effort to tip it forward.  Since I have cats and grandkids I don't want to see smashed, I decided to shorten the back to 12 inches and put 7 inch feet on the front.  This way even the smallest amount of pressure from behind will cause the baffle to lift up off the floor at which point it is no longer weightless.  Also, the thought of 24 inches behind the speaker was scary since I'd be tripping over it all the time.

So with the following sketch I went to work...




Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/02/19 at 02:30:45


I ordered 20 BF of OAK and started jointing it up. I decided to make it solid once I got started... more mass, and that's an important component in the Betsy baffle design.



Steve





Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/02/19 at 02:33:12


Now to figure out how to attach them to the baffles.



Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/02/19 at 02:38:07


Here is another shot of the oak bases.  I'm going to dowel them into place and use lag bolts so they can be easily removed.



Steve

Title: Re: Steve's BIG BETSY Project
Post by deucekazoo on 07/02/19 at 14:18:15

Steve, looking good. I can't wait to see how they look all put together. They are going to be one heavy speaker. You will need to get a dolly to move them around.

Title: Re: Steve's BIG BETSY Project
Post by Geno on 07/02/19 at 14:45:37

Steve,

Thanks for letting us ride along with you on this!

So these will be Bass baffles? To pair with the normal Alnico Betsy's?

What Bass driver are you using?

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/02/19 at 15:11:34



Steve said "Fixing the side where on the last cut I blew out a large chunk of Wenge... and then lots of sanding."

Yep ….. when routing the outside edge of just about any hardwood, it is VERY easy to blow a chunk out of the wood …..
I have done that several times and it makes you sick to your stomach to mess up a beautiful slab of hardwood.

At this point ….. I just use a band saw, trace the shape of the baffle from a template, cut out the baffles on the band saw close to the line and then clamp the two baffles together and use my belt sander to make the edges as smooth as a baby's butt …..

Of course, Steve's baffles are too big to easily (if at all) run through a band saw ….. so he did something different.

I am impressed ….. for anyone who has never attempted a project like this, there is a lot more to it than you can even imagine.

Very nice ….. !!!

Happy listening,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/02/19 at 23:11:11


Thanks for the kind words Randy... yea, just too heavy and large to cut on the band saw unless you cut the pieces before they are glued together. That was my original plan until I found out my bandsaw didn't like 2 inch thick Wenge! I'm sure it will cut it fine, but being somewhat new at this, I didn't feel it was the time to be increasing the blade tension ; ).

My blow-out looked the like a scar on Mars... I packed it full of Wenge splinters from the cut and it's very hard to tell anything happened. A lighter wood would have been a different story.

Steve




Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/02/19 at 23:20:00


Yes, these are intended to be bass baffles to pair with the Alnico Betsy speakers. My hope was to find a lower efficiency woofer with a steep natural roll-off that I could either series or parallel with the Betsy and in either configuration not use a crossover. Since the Alnico Betsy driver is more sensitive and has over 3 octaves higher response, even though both drivers are hooked together, the high frequencies will naturally go to the Betsy driver, and the low frequencies will naturally go to the bass driver. Any overlap is seamlessly canceled by running the bass drivers out of phase relative to the Betsy drivers.

I found the perfect drivers, some Seeburg DDS1 drivers. Basically vintage disco tech drivers with alnico magnets and cloth surrounds. Probably about 88/89dB from what I can tell.



I painted them black to match the Betsy drivers. You can see them in one or two of the previous pictures in the background of my shop.

When I got these drivers I laid them on the floor next to my Betsys and hooked them up as described without a baffle.  It was perfect.  You practically couldn't hear them which is what I wanted.  I could have lived with that just fine, but once I got the image in my mind of a 2 inch thick solid hardwood Betsy at a full 42 inches tall I just had to make a pair.  Couldn't help it.

The first full listening test was to be honest a lot more bass than I was expecting which was great!  Then when I figured out to wire the woofers 180 degrees out from the Betsy drivers the mid-bass overlap disappeared and so far it was for my personal taste the best sound I've possibly ever heard.  There was zero mid-bass bloat or room contribution in that critical area and I found it so refreshing that I was just spellbound by it.

I'll put together some photos and more impressions about the sound in the next couple days.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/02/19 at 23:26:18



Quote:
there is a lot more to it than you can even imagine.


Yup, like when I found out half of my Wenge was quarter sawn and half wasn't so I had to rip down all that wasn't and rotate the pieces 90 degrees and glue it back together without loosing the 1/2 inch of wood from the four cuts on the table saw.  

The biggest lesson I learned is that you want more wood than you need and that a good sounding stereo provokes a lot less mistakes than a bad sounding one!

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/03/19 at 00:34:02


So here are a couple more shots of the front feet getting put on, and from this point forward, they got carted into the listening room.  I'll take some pics of the finished baffles next.




Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/03/19 at 00:34:36


By this point I got too excited and forgot to take more pictures... happens every time!






Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/03/19 at 02:10:56



Quote:
Steve, they look great!!

Shop looks great as well.

Guys, you don't even want to know how much I cringed to see Steve's old table saw sitting out in the rain with a crustacean of rust on the top. But the dam thing still worked!

Zygi


Hehe... seeing that saw set out in the rain all those years was instrumental in motivating me to build the shop.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/03/19 at 21:15:51


Quote:
Obsession is a bad thing, or is it??


It gets things done ; )

Steve

Title: Re: Steve's BIG BETSY Project
Post by Dana on 07/06/19 at 15:43:57

Ya know... If the woofer thing doesn't work out what a beautiful coffee table with a space for your bowl of chips.

Or maybe a pair of subwoofer coffee tables that way you wouldn't have to worry squashing the guests when they get a little rowdy.

Actually thanks for sharing I hope they sound as good as they look.

Dana


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/11/19 at 03:44:39


Here are a couple teaser pics. In this particular configuration the photo shows it as a full-range speaker rather than a bass baffle, so it is quite literally a perfect scale replica of the Caintuck Audio Betsy Baffles.  



As I'm sure I said in earlier posts, it was a lot more effort that I bargained for but turned out to be well worth it.  This is one of those rare speakers with so much mass I can't lift it.  It feels like a giant magnet stuck to a steel floor.




Because the driver is large enough to accommodate heavy binding posts, the speaker wires can be connected directly to the driver itself.

-Steve  :)


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/11/19 at 03:58:23


My bass baffle implementation is non-duplicatable because it is based on obsolete vintage alnico Seeburg drivers from the 1950's.

The full-range drivers shown in the picture are a current production driver from a small company called Lii-Audio who specialize in crossover-less full-range drivers.  The model is the F15 which is the largest driver in their line, and the least expensive.  I'm not sure it would be priced so reasonably if more people heard it in this magic Caintuck Audio Betsy Baffle design.  I'm not blowing smoke here either.  This combo is producing more low bass than the smaller sized baffles featuring multi-15 inch driver arrays by a huge margin.  

Here is a spec sheet on the drivers used.




Steve

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 07/11/19 at 05:16:51

Damn Steve, that is bad ass!  As an owner of Randy's Betsy Baffles and of his Bubinga 15" Augie bass drivers, I have enough knowledge and experience with Randy's designs to fully appreciate what you have done here.  

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/11/19 at 05:20:39


The efficiency of these drivers in combination with these baffles is easily at or over 100dB 1w/1m and that is all the way down to 50Hz at which point it begins to roll off. I realize there are many 100dB speakers out there but consider this, many are rated at 2.83v not 1w/1m which translates to a lower figure, usually by around 2dB. Also many 100dB speakers are using a crossover and more than one driver. Also many full-range drivers that claim to be 100dB have absolutely no bass compared to this, which is a crossover-less full-range 15-inch driver with only 14 grams of moving mass.

As a result, its sound is unique, reminiscent of the vintage drivers from the 50's that were nice and tight, which this certainly is. The difference is that there is no cone break-up at the listening levels you would be able to tolerate in your home. It sounds exactly like the original Betsy driver, but with an octave lower bass. The top end is the same, slightly rolled response that I never have a problem enjoying.

The Alnico Betsy drivers by comparison are faster and more extended in the top end. A pair of the Betsy speakers with either driver create a believable you are there sound stage with reference precision.  The F15 drivers in the big betsy baffles create a believable they are here sound stage (which is rather different) with dynamics and projection better than any speaker I have ever heard, proving the validity of the special shape of this baffle design.

The F15 drivers in these baffles will get louder, hit harder, have more bass, and sound bigger than any other Decware free-standing speaker driven by our larger TORII and ZMA amplification with nothing more than a 2 watt Zen Triode amplifier! It's simply insanely good and incredibly hard to believe when you hear it. For all those who own a 2 watt Zen Triode and wondered what it would sound like with a 40 watt ZMA, this is the same result only better because no other speaker has this projection, not even my corner horns.

However with the F15 driver there is no doubt in my mind, especially for Zen Triode owner's that even a triple-sandwich of MDF or cabinet grade plywood used to create a Big Betsy on a budget would provide reasonably similar results, which is scary exciting since the drivers are less than $500 a pair.

I will have these set up in my room indefinitely, so a great time to hear them would be 2019 DECFEST in October 4th, 5th, 6th. Between these and Bob's re-designed HR-1's , the Omegas and Randy's baffles there will be quite a bit of new sound this year! Of course that doesn't even include all the anniversary mods and the new soon to be released CSP325 preamp!

Happy listening!


Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/11/19 at 05:33:21



Quote:
Damn Steve, that is bad ass!  As an owner of Randy's Betsy Baffles and of his Bubinga 15" Augie bass drivers, I have enough knowledge and experience with Randy's designs to fully appreciate what you have done here.


Thanks Jeff... they are blowing my mind pretty hard on a number of different levels. The frequency balance is so good. Warm, full, and without any detectable peaks whatsoever. Just a joy to listen to, and to my great satisfaction they have the scale of the big horns, specifically my corner horns, and the imperial horns, which I wasn't frankly expecting.  Also many times the impact and projection, so live sounding and simply effortless. They will absolutely faithfully reproduce a full orchestra at live levels with convincing realism which is rare because you don't normally hear this sound without a box or a horn or both...

I just can't get used to the live playback levels. Listening to 'Los Invisables- Santana' as I write this and it feels exactly like it did one evening listening live around the pool and bar area at a place in St. Thomas Island while on vacation. It's definitely a demonstration of sound getting bigger instead of getting louder, but man you can feel it in the whole structure, the bass performance has literally destroyed all of my other speakers including the corner horns.  I certainly didn't expect that! The Audio Gods have already let me know that making the same size baffle in a rectangle will ruin the sound, and I've seen and can understand exactly why I just haven't figured out the words to explain it yet.  A living demonstration of Sacred Geometry is the best I can do at this point...  I mean the thing that blew my mind the first time I ever head a pair of Randy's Betsy Baffles was the fact that they had such good bass when I was expecting basically none.  It shouldn't be happening, and now that I have scaled the speaker up the effect as well as the fascination is the same, with performance an octave lower and over twice as loud, it just shouldn't be possible.  Fun Stuff!

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/11/19 at 06:03:04


I just thought of how to describe the sound...

The sound of this speaker is what you always wish would happen when you turn up the volume of your stereo but never does.

Steve

Title: Re: Steve's BIG BETSY Project
Post by deucekazoo on 07/11/19 at 14:13:38

Steve, those look awesome!!! Can't wait to hear them at Decfest.
I wonder if you could add one of Randy's planar tweeters to those to extend the highs a little.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/11/19 at 17:15:07

Steve,
Do you believe that more mass in a open baffle is a good thing?
The ones that I made are HEAVY, but I have heard others say that it didn't matter.
What's your take?

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 07/11/19 at 18:08:46

Ahh... the age old debate Mr. Donnie.  

Does size matter?  Or is it how it's used?  ;)

Title: Re: Steve's BIG BETSY Project
Post by ScottNC on 07/11/19 at 18:14:52

Like Jeff said:
Damn Steve...

There is no truth to the old saying, “let sleeping dogs lie”!
All I have to do is move a few plants and there is room for those absolutely stunning speakers, I have no doubt they are all you say and then some. Very cool.

It truly never will end will it?

Best Scott

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/11/19 at 23:01:41



Quote:
Steve,
Do you believe that more mass in a open baffle is a good thing?
The ones that I made are HEAVY, but I have heard others say that it didn't matter.
What's your take?


In a word yes.  

Mass and stiffness seem to be the key interrelated ingredients.  Remember, in a baffle like this, the speaker and baffle are one.  Sound projects off the baffle in the shape of the baffle both front and rear.  It is not projecting like a flashlight beam from the speaker cone, the energy is already in the wood before the wave is launched, it therefor launches from the wood and the cone.

Those who say it doesn't matter are correct because everything is relative.  When you don't have the money or time to go with high mass, then you don't hear high mass and conveniently high mass doesn't matter.  Once they hear a high mass copy of a low mass speaker, then suddenly it will matter... ignorance is bliss in this hobby as we all know.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/12/19 at 01:44:05

Ignorance is one of my specialties!

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/12/19 at 05:25:51

Ignorance is the realization of all possibilities.  It is unbound by knowing.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/12/19 at 06:26:02



Quote:
Like Jeff said:
Damn Steve...

There is no truth to the old saying, “let sleeping dogs lie”!
All I have to do is move a few plants and there is room for those absolutely stunning speakers, I have no doubt they are all you say and then some. Very cool.

It truly never will end will it?

Best Scott


Hehe... no Scott it never ends, thankfully.  The key to getting through the journey without financial ruin is  A) have gear that sounds so good you don't really care if you do or not.  That way there is no real pain in going without.

Tonight I watched the High End Munich Video on Youtube : https://www.youtube.com/watch?v=58Dt0CM-6Uk&feature=youtu.be&t=79 and played the recordings I heard on this system and I realize that the Audio Gods have taken a real favor to Randy with this design because what I am hearing from these large Betsy's are making the video sound rather stupid, and we're still on 2 watts.  I have not heard the speakers on anything more than the 2 watt Zen Triode amplifiers so far.  

As Bob Ziegler, the other ear in the Decware trifecta of straight shooters will recall, the loudest we ever got anything in this room without distortion was with the legendary corner horns driven with the secret Decware OTL amplifier which was basically 20 watts of 6C33C SRPP amplification that I decided was too esoteric and expensive to add to the Decware line.  It was an ass kicker, remember Bob?

Believe it or not these damn baffles with a 2 watt Zen Triode are actually just outperforming that, by about 30% I would say.  I'm afraid to put more power on them because I might get to a nirvana that makes anything less taste like McDonnalds.

In fact, Bob, imagine 4 DNA2 speakers side by side on each channel with the Zen Mystery Amp driving them at full tilt... this probably doesn't go as low, but so far I have not heard anything that would suggest it didn't.  I listened to the famous Halucianenic hippo track from Randy's demo disc and I actually nearly mirrored the performance from the Imperial horns which were using 90dB woofers driven by 60 watt Zen Torii Monoblocks.  

I'm sorry to be so chatty about these speakers, but I'm just trying to capture my mind getting blown in real time and we're at the full burn-in point with these on a well seasoned amplifier, so it is possible to start getting really serious about what they can do well and what if anything they lack, which I already know is nothing.  As I mentioned before, they bring the performance to your listening room with such a live dense presence that you have no idea what the actual recording venue sounded like.  The original small Betsy's in contrast do the opposite which is to transport you to the the venue and accurately reproduce large spaces.  

I'm really starting to wonder what a triple laminated plywood copy of these would sound like.  My guess is so similar most would say the same.  The extra perceptive would give the speed advantage to the solid hardwood, but the extra damping of the plywood or MDF could create a more relaxed sound.  I just know that if you own a low power tube or solid state amplifier, this is going to be the holy grail of bang for the buck, and isn't that ironic because that's what this baffle design has always been.  I thought Decware was the leader in that category, but Randy now sits at the top of that pile.  

All I can say is that if you watch the original Betsy Baffle video I did you can hear for yourself how seemingly impossibly good they are.  Scaled up by 800% it is literally scary.  It completely re-inforces my recommendation for the Caintuck Audio Betsy Baffles.  I think everyone should have a pair regardless of what you have now, because they will constantly challenge your indoctrinations.

Steve


Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/12/19 at 15:11:08




Quote:
I realize that the Audio Gods have taken a real favor to Randy with this design because what I am hearing from these large Betsy's are making the video sound rather stupid, and we're still on 2 watts.


Steve ..... many thanks for the kind words concerning the Betsy baffles.
However, I usually chalk up any modest success I have had in my speaker building projects to the proverbial "blind squirrel finding an occasional acorn" .....

It is certainly true that since 2015 I have built literally dozens of open baffle speakers in various shapes and sizes using a variety of drivers.



The Betsy baffles that I have been offering to the public reached their current configuration based on a few things.
I found that baffles with "rounded" sides sounded consistently better to me than rectangular baffles.
Flying in the face of the "received wisdom" that a speaker driver should be at "ear level" of a seated listener, I found that a good full range driver would throw a full height stereo image with the driver much closer to the floor. An added bonus was that the proximity to the floor enhanced the lower midrange and upper bass frequencies.
A third consideration was that the speakers should be affordable, small enough to ship a pair in a single carton and reasonably attractive to fall within acceptable boundaries of the WAF.

Of course, having a pretty revealing front end and a Decware SE84UFO amplifier that images like crazy made it a lot easier to actually hear differences in the various baffle configurations .....

A couple of years ago, one of the Decware forum members (Mike - maddog07) brought a pair of Betsy baffles to the Decware Fest fitted with larger Audio Nirvana alnico drivers. I was able to hear them and was very impressed. However, these drivers alone cost about 1K a pair which is a bit above the price most of my intended customer base wants to pay ..... so I never offered them as an option.

The Lii Audio F-15 drivers are certainly cool looking and the price is attractive. I have ordered a pair and will check them out in a pair of my standard sized baffles to see how they work.

Of course, they will not make the low end and scale that the BIG BETSY baffles are creating ..... but my gut feeling is that they might be pretty "interesting" .....

So many options ..... so little time .....

Happy listening,
Randy

 

Title: Re: Steve's BIG BETSY Project
Post by lazb on 07/12/19 at 15:23:06

Randy and Steve,
Random thought just popped into my head! Is there any possibility that the "rounded" baffles behave sonicly(sp?) somewhat like the "wings" on Infinity IRS series speakers?

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/12/19 at 17:12:47



Hi lazb,

Good question ..... but not being a "numbers guy", I would only be guessing at the reason they work like they do.
I'm sure that Steve is in a better position to explain the "whys and wherefores" .....

When I first started experimenting with open baffles, the only thing I knew for sure was that there was something different about the sound that I wasn't hearing from the box speakers that were in my listening room at the time. It was a "natural" sound and made me want to spend time listening to music ..... and that was enough to make me spend some time "butchering wood".

You know how this hobby is ... no matter how good something sounds, you just know that it can be improved on ...

I went through quite a few different sizes and shapes and drivers .....







The one thing that seemed to be consistent was that the baffles with the rounded (or asymmetrical) sides disappeared better both visually and sonically. They also sounded "smoother".
I remembered reading somewhere that straight edges had some disadvantages when it came to sound ..... but couldn't remember the reasoning behind it .....

Now, it could be that my conclusions were simply what I wanted to believe ..... but I don't think so. When I made the first pair of the "low boy" barrel shaped baffles, all of the other baffles I had made went in the scrap heap, and I never looked back.

Truthfully, some of the speakers in the photos above sounded pretty good ..... but some of the drivers used and the way they were built would have been a nightmare to make and ship.

Simplicity can be a very good thing .....

Best wishes,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/12/19 at 18:07:49

I do wonder about the asymmetrical loading of the drivers?
My OB's have the full range driver offset 1/3 over and are also not in the center of the radius of the baffle, it is not centered on purpose.
I did it because I read that it would help the driver from "beaming"
They seem to sound pretty OK in my room.



Title: Re: Steve's BIG BETSY Project
Post by Dana on 07/12/19 at 21:29:59

At about 28 minutes https://www.youtube.com/watch?v=EEh01PX-q9I

He talks about wood vibrations and density and does some tests and then provides a solution with a vibration absorbing compound Decidamp.

Would this be effective as an adhesive for a multilayor baffle sandwitch?


Title: Re: Steve's BIG BETSY Project
Post by maddog07 on 07/12/19 at 23:54:07

I gotta hear these things Steve - they look fantastic!

there is research out there that lends credence to the shape of Randy's baffles.  On first thought, one might think "round" would be good - research shows that "round" is actually one of the worst shapes for OB.  "Irregular" baffle shapes are theoretically the best acoustically.  The same research tends to support mounting the driver "not in the center" of the baffle either.

For my regular Betsy Baffle "kit" that I got from Randy, I modified the baffle base so that it tilts the main baffle back about 15 degrees.  And I added a brace that runs vertically from the top of the base to the top of the baffle, right in the middle, with a half-circle cutout for the back of the Betsy frame and magnet.  This brace is rigidly attached to the middle of the back of the baffle, except for where the Betsy protrudes out the back.  I tend to be a little anal about "mass" and rigidity and thought they needed something...  The wood back brace is 1" think material. Did this make an audible difference?  Who knows, I didn't try them without it.  I just sleep better at night knowing it's there.  And they sound wonderful.  I also had a pair of 945's.  I compared the 945's to the Betsy's a few times.  What I heard, was not what I expected.  To my aging ears, which I'm certain wouldn't reach 15khz in a test, the Betsy's and 945's sounded more alike than different.

With my custom Hawthorne Audio Trio's, which use "mounting plates" to decouple and attach the actual drivers to the main baffle... I have made numerous mounting plates that allow me to use a multitude of full-range mid/hi drivers with the main Hawthorne Trio baffle which has two 15" Augie bass drivers per baffle - four total for the pair. (one 15" at the top, one at the bottom and the full-ranger in the middle).  I have never heard more real, more natural sounding bass.  And there is absolutely no issue with "quantity".  This setup pressurizes the room like nothing I've ever owned or heard.  I think I could lift the house off the foundation with enough volume.  They are more than capable of giving you a "gut massage" in terms of quantity.  They have "bass you can feel" even at low volumes.. just like sitting in the first few rows of a jazz or blues club.
To date, I have ran an Audio Nirvana 15" cast frame ferrite full-ranger in these, an Audio Nirvana 12" cast frame Alnico driver, and been quite pleased.  I just completed mounting plates to run a pair of Betsy W.O.W. drivers paired with Dayton AMT's like Randy demo'd at Decfest in 2017 to run in the center position of the Trio OB's.  I haven't actually put them in the Trio's yet, but I'm expecting "good things" from this configuration.

This thread is putting ideas in my head - not always a good thing.  I have never tried running one of the Augie bass drivers off the same amp as the full-ranger(I use a Torii).  The Audio Nirvana drivers are really efficient... way more than standard Betsy's.  I've never measured them, but I have had the Betsy's and AN's side-by-side and switched back and forth and you have to adjust the volume control significantly.  More volume for Betsy's, less for AN's.
The Augie's have a stated sensitivity of 89db 1w/1m if memory serves.  I don't think one could run an Augie and any of the full-rangers I have tried off the same amp - that's just speculation.  I should probably try it and see.

so many ideas, things to try, experiments - so little time.  Thankfully retirement is approaching - I'm going to be busy for at least a couple of years....  Steve I envy you so much - you have no idea - making a living doing something you love and truly enjoy - that is a blessing my friend - a true blessing.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/13/19 at 00:35:18


With regards to the baffle sandwich:  On the Betsy Baffle design, the driver is screwed directly to the wood baffle.  The baffle is energized and becomes a sound transducer.  When I scaled it up for the Big Betsy, I expected with all the additional mass that I wouldn't feel much energy in the baffle.  I was wrong, the amount of energy was exactly the same as the smaller Betsy, and interestingly the pitch was about the same, not lower on the larger baffle as I expected.  This made me realize that probably the last thing that I would want to do is create a co-mass-layer-damped lamination that was inert.  Nevertheless it would be fun to do it anyway and put the two approaches side by side and see what the effect on the sound  actually is.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/13/19 at 01:26:57

Giving demos all day today, still at it.  The Big Betsy is just wrecking everything...  Make sure not to play these if someone is interested in any other speakers.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/13/19 at 04:03:05

Watching the two gentlemen here tonight listening to the Baffles is like watching a video of myself going through the mind melt... it's a nice conformation.  My advise is do not attend DECFEST 2019 because it will upset your apple cart.


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/13/19 at 04:30:49

Yea, ...they'll never be the same again.

After awhile we put the ZKIT60 in and cranked things up a notch. I gained a new appreciation for this amplifier. Guaranteed there is no better sounding 60 watt amplifier made for 800.00 on the planet. You can put my name on that.

It wrecked them really bad and impressed the crap out me as well... great job Dan!

Then as the final lesson for the night, being solid state guys, I told them that some tube gear actually hits a lot harder than solid state, and after hearing the ZKIT60 they simply couldn't believe it.

Up came the Zen Mystery Amp.  Only 40 watts, but it simply hammered it. They were literally stunned. I know they're talking about it right now on the long drive home.

It was the first time I heard the Big Betsy on anything more than 2 watts and I was extremely pleased at how well they deal with power. Never does the room become compressed, and OMG the hit is just insane.

That said, and as I pointed out, the difference in performance between the two amps was about 20%.  However the difference in price was 7.5 times as much!   $800 vs. $6000 so the clear winner in that equation is the ZKIT60.  Perhaps the all time king of diminishing returns, which btw, is why we carry it.  If you want power that sound like Decware tube gear, but don't have the bread for it, this IS your answer, trust me.

And these damn speakers -- are another UFO25... When the two are paired together it is to put it mildly, memorable. This is the kamasutra of audio, no question about it!

And here's the best part!!! Speakers are too heavy to beam up so those UFO's in the videos are going to have to come up with a new strategy!


In all honesty, after 30 years of doing this, and walking through many hi-end shows with X-RAY vision, I never dreamed a stereo could sound like this, or much less that it would be mine.  God I love my job!


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/13/19 at 06:03:50


I have to say this, because it's true.  We listened to the bookshelf speakers, the DNA2's and the Big Betsy's.

Before any of that -- these two walked in on Randy's Hallucinogenic Hungry Hippo demo track with the worlds lowest textured bass. It was playing on the Zen TORII Mono's driving the ZOB's and Imperial SO horns... you know, the epic demo of the 2018 DECFEST. If that's not setting the bar rather high... before a listening session even begins...

Anyway, we started with the UFO25 driving the DM945's which sounded great, even after the Hippo demo, and they were both pleased. Problem was, the song selection was grade B recordings streamed on demand as they asked for them.  Despite that the speakers and amp still sounded good.  After about 10 minutes (all telling secret numbers) they requested the 100dB speakers I spoke of.  That was at 5:00 P.M. Four hours later they wanted to hear the DNA2's. Now get this...  1 minute 45 seconds and the request was made to put back on the Big Betsy. And I have to agree, while the DNA2 was silky and exquisite sounding, the Big Betsy spanked its ass so hard it was like a toy.  Almost embarrassing.  

Also of noteworthiness is the fact that these two are seasoned veterans who take audio so seriously they have 6 different pressings of the better LP's in their collection. And they of course brought them. And we of course played them.

Probably the highlight of the evening was during the ZKIT60 demo. I had my digital feed, complete with ZROCK2 going into the ZKIT60 and we started listening to some BORRIS BLANK aka YELLO tracks that really flex a soundstage with deep dynamics and it was SOOO good.  Then I got a rare pressing of the same thing out and put it on the turntable, and literally the difference was a 353% improvement. Holy hell did it have some slam... so dense and liquid. This fried everyones mind pretty hard. The source is what you hear.

So another fun evening.  Also the AC broke down on Monday, the repair crew was here all day today during the demo installing a new unit and everyone had sweat dripping off them for over four hours but we were all so distracted by the euphoric sound that we forgot we were hot.

Now that it's hooked up, I am spending the evening listening to these speakers on the ZMA with anniversary mods. I have it turned up as loud as I can really handle it and I can say that the Zen Triode Anniversary amp at 2 watts hits harder and gets just as loud with these magical 100+ dB speakers. Power wise you can not tell any difference between the two amplifiers except for the hit, which against all reason the single-ended amp with 2 watts is hitting harder making it sound like it has more power. I'm not kidding folks.

I'm setting here right now listening to the speakers on 40 watts and it brings absolutely nothing to the table over the 2 watts. It's a completely different story however on 94dB speakers. With those I was always on the fence, 50/50. And that's not completely true... I would gravitate towards the 40 watt because of the majestic headroom it had and the ability to turn the music up really loud without tanking the sound. But now, with these 100dB+ speakers that have BONE CRUSHING CLEAN BASS it just completely illustrates that low-power high-efficiency is the holy grail in audio reproduction. Especially and perhaps exclusively only when it is a true full-range, single-driver, crossover-less point-source. This is something that almost no main-stream hi-fi speakers qualify for.  

I'm now thinking perhaps an appropriate name for these baffles would be the Big Fun Baffles!

Steve







Title: Re: Steve's BIG BETSY Project
Post by TomR on 07/13/19 at 15:17:45

Mr Steve,
Did you do any trials with the Seeburg drivers and the Betsy, or just scrapped the idea ?

Just wondering, I have a set of the same 15" Utah drivers, That have never found a home.


Tom in Lafayette

Title: Re: Steve's BIG BETSY Project
Post by Brian on 07/15/19 at 03:07:21

I can't add anything useful to all of this! But this speaker has me so excited I have to make some sort of comment. The "Big Bastards" with the F15 full range, sound like your best speaker yet!

I like your trammel points - classy.

Not being qtr sawn, you got a more glowing color. I like it.

Brian

Title: Re: Steve's BIG BETSY Project
Post by Showme on 07/15/19 at 15:28:40

Now the trouble is for me, not being a woodworker, what am I to do? Well I will await Randy’s report on the F-15’s in his baffles. Maybe they’ll be close enough. We’ll see.

Title: Re: Steve's BIG BETSY Project
Post by bikehappy1 on 07/15/19 at 16:02:30

BAOB. Big Ass Open Baffle.  

Title: Re: Steve's BIG BETSY Project
Post by lazb on 07/15/19 at 18:20:37

this looks to be the driver and ON SALE !
https://www.lii-audio.com/index.php/product/recommended-15-full-range-speaker-driver-for-music-loudspeaker-with-tube-amplifier-f-15-in-pair/#reviews

Title: Re: Steve's BIG BETSY Project
Post by maddog07 on 07/15/19 at 22:53:57

has anybody besides Steve actually "attained" a pair of these?  If I read lii Audio's website correctly, these are now on sale for $399 for A PAIR...!!!
Or has anybody ordered anything from them?  Just wondering what they are like to deal with - being that they are located in China.
4055 Nong Gang Rd.
Jianggan District
310020 Hangzhou, China

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/15/19 at 23:53:45



Hi Mike,

I ordered a pair via their website on 7/11/2019.
An email was received on 7/15 telling me that they had shipped with a UPS online tracking number.
When I checked the tracking number, it showed that the speakers actually shipped on 7/12/2019 and they will be delivered on 7/18/2019.

The shipping point of origin is Baldwin Park, CA, United States.
Shipping charge - $49.00

They accept PayPal and seem to be "on the ball" .....

If the drivers are as good as the service, I have high hopes for them.
If they sound anywhere near as good as your AN alnico drivers did in my standard baffles ..... it looks like I might have to make an addition to my product line .....

I recently sent an email to Steve and Bob suggesting that they start building the BIG baffles and offering them in the online store ..... no reply yet. Steve is probably still recovering from building the first pair .....

The BIG baffles are definitely beyond my woodworking tools and skill set ..... but Steve and Bob can probably stay as busy as they want to be offering these beauties (in some configuration).

It's not like Steve has anything else to do ..... other than build 25th anniversary equipment. doing mods, etc. .....

Best wishes,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/16/19 at 04:14:58


Indeed, I know I wouldn't be in a position to build another pair from hardwood like this because of time, so it would be up to Bob Ziegler and I wouldn't feel right about asking him until October when he is here to hear them first hand.

This speaker is as far as I can tell probably going to have to be shipped freight. Because of that alone, if we offered it, I wouldn't have a 30 day trial. Doubtful that would ever really be a sticking point since the way they work in a room and the way they sound will ensure success in every case, just as Randy's smaller ones do.

Perhaps Randy will be temped after he receives his drivers and brakes them in to hear them in the big baffles and make a pair out of plywood... you never know.

I have gotten a good vibe from Lii Audio, and find them eggar to please.  Their other products look enticing as well.  You know me, always for the little guy, and clearly that is the case here.  These drivers aren't made in giant Eupa factory in China but by small business like Decware. I have communicated with the owner and designer of the driver Mr. Lii and we look forward to see what things can happen next. ; )

As far as the Big Betsys with the F15 drivers go, it's my opinion they are too good not to build and sell. On more than one level they spank all of our speakers... the ZOB, the DNA2, the HR-1, the Corner Horns, to a degree that they simply have to be built. My concern isn't about so much offering this exact pair or other hardwoods for 6 or 7 grand, but finding out if the sound can be duplicated in MDF or plywood.  Because if it can, that's going to be a speaker everyone who is serious can easily afford to buy or build once they hear it.

I'm a little scared what I will hear in a side-by-side comparison, because there is a energy and speed associated with this hardwood pair I built that I honestly wonder if it can be duplicated in other woods, and how sensitive that's going to be.

However, doing the math, since the speaker is basically twice as good as everything else we've offered on it's own without augmentation, that means that if a mdf or plywood baffle sounds only 70% as good, it would still be 30% better than everything we've offered... the thing is, it is possible that either material could for some Godforsaken reason sound better than this hardwood. It could be 30% better yielding a final result of 130% improvement. Also with laminated MDF or plywood is the opportunity to make co-mass-layer-damped panels by sandwiching asphalt paper, dynamat, linoleum, etc., between the layers. Of course if it did sound better I would prefer to not know about it since I love my pair and ignorance is bliss in this hobby.

So you may be shocked to hear me say that on more than one level they spank all of our other speakers. (not every level, but 2 out of 3 sort of thing) Two reasons for this. 1) They have more bass than highs, not the other way around, so they always sound good. 2) In these baffles they are at least 100dB or higher and everything else we make is 96/94dB or less. You wouldn't think 4, 5, or 6 dB or maybe 7dB would make that much difference but it is a complete game changer. You no longer have a 2 watt amp, you now have a 40 watt amp with incredible slam. This excites me because we all know the ZMA 40 watt is 6 grand and you can get a 2 watt Zen Triode for 1 grand. Just to be crystal clear about this, these speakers on a 2 watt zen triode amp hit as hard as a Zen Mystery Amp on our fabulous 94dB DNA2 loudspeakers! It seems impossible but it's true.



Steve



Title: Re: Steve's BIG BETSY Project
Post by ScottNC on 07/16/19 at 05:13:51

Being as happy as I am with the DNA2’s, I’d venture a 10%? of (I bet you gotta pretty good guess)...let’s move this along🤓
Best on this this one, no doubt...
Scott
My offer stands as long as they take a while to build😆

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/16/19 at 10:51:33

Hmmm, I have 4 sheets if .750" MDF just sitting in my shop without any real plans......

Title: Re: Steve's BIG BETSY Project
Post by dank on 07/16/19 at 12:53:07


Quote:
Hmmm, I have 4 sheets if .750" MDF just sitting in my shop without any real plans......


4 sheets seems excessive, I'm going with double thick which required 2 sheets, 1 1/2 actually if you can find 3/4 sheets (4' x 6') somewhere.  My radius turned out to be 43" and the measurements seem very close:  42" high, 36" wide at the widest point, and 24" wide at the top and bottom.  They are fairly large, standing almost as tall as the corner horns.

Once the feet go on, do they stand vertical or are they tilted back a few degrees?  I guess I'm just planning on tilting them enough so they seem to best point to the main listening chair.  Also, I see the speaker is mounted from the front with a router round over bit used on the back, is there a reason for this?  Would I get worse results if I used the round over bit on the front and mounted the speaker from the rear (probably with speaker cloth between the speaker and the board)?  








Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/16/19 at 15:35:59

That MDF freaks me out with all that toxic dust.  If I were to make a pair I might cheat and start with a maple blank like this one:  https://www.foodservicedirect.com/john-boos-oil-finish-hard-rock-maple-industrial-top-48-x-34-x-1-75-inch-1-each-21369953.html

Title: Re: Steve's BIG BETSY Project
Post by Showme on 07/16/19 at 16:13:01

HD and some of the big box stores sell butcher block countertops in sizes that would accommodate 42" x 36" slabs. They are from 1.5" to 1.75" thick. They stain beautifully. I just built an audio rack using it for shelves and all thread rods with stainless steel nuts and washers for the uprights.

Title: Re: Steve's BIG BETSY Project
Post by maddog07 on 07/16/19 at 23:19:07

Hi Randy...

now you got me thinking I need some of these lii drivers!  Does anybody know what the magnet material is?  And how much power they can absorb before going up in smoke?  Just what I need - another set of mounting plates for the Trio's, and I'll have no less than 5 different variations/flavors of mid/hi drivers to go with the Trio's four Augie's.  Does this ever end?  Us old fogies already know the answer to that!  I have some younger audio pals who still think there is an "end all" system!   ;D

I use Baltic birch... and am more than happy.  I also use a co-layer-damped approach with all my OB's.  This, after experiencing the baffle transmitting at least as much vibrational energy into the room as the drivers!  And not "good energy" either, but a buzzing akin to a swarm of Africanized bees.  And the side rails of my Trio baffles are sand filled!  After this experience, I added mass to the baffles, added rear braces and started decoupling the drivers and the mounting plates from the main baffle.  To my ears, this cured the problem completely and the overall sound became much more natural and organic.  

Also... another "conventional wisdom" practice I tossed aside when I started experimenting with OB's - toss any kind of floor spike out.  I went to great lengths(and expense) to add 1/4" plate steel outriggers thru-bolted to the 2" thick, almost 2 ft. square basses, with 2lb brass footers.  These coupled through thin carpet to a concrete floor in my room.  This seemed to "amplify" energy in the baffle instead of draining/dispersing it.  I removed the steel outriggers and brass footers. I now place a sheet of some of the same material I use between drivers, mounting plates and the baffles for decoupling/dampening, under the bass of the baffle. (closed cell neoprene foam - this works great under components too)

I think Randy, has perhaps, really landed on the "magic formula" with his K-I-S-S approach to the Betsy Baffles.

When I first installed the 12" Audio Nirvana cast frame Alnico's in a recommended 5.6 cu.ft. reflex box... I had an "Oh No" moment - there was too much bass.  And I mean way too much.  However, and thankfully, the drivers pretty quickly loosened up and produced mids and highs.

The 15" Cast frame ceramic Audio Nirvana drivers are more sensitive/efficient than the Alnico's.  The Alnico's are "smoother".  I have A/B'd the ceramic and Alnico's side-by-side in my custom Trio baffles.  You have to adjust for volume differences, but even getting the volume matched within a fraction of a db, the sonic differences between the two are not subtle.

I have also A/B'd them in reflex boxes.  The ceramic's are too hot for my taste in a box - probably too hot for most people.  The Alnico's need no bass augmentation in a reflex box... with a current source output "type" amp like my Torii III or a Papa Pass FirstWatt J2 they sound superb.
Placing the Alnico's in a larger OB makes them sound "laid back" and soft compared to the ceramics.
 
The 15" ceramics in an OB are more resolute, more micro and macro dynamic than the Alnico's and way more so than my current generation Martin Logan stats - no joke!  An audio bud of mine sums it up best and characterizes the crossover-less, full-range, OB's as "snappier" than the stats.  It causes a bit of cognitive dissonance the first time you hear the two side-by-side.  Your brain just doesn't want to believe what your ears are telling it.  
My point... I can completely relate to what Steve is talking about "slam", hit, etc. from these lii Audio drivers in that massive baffle.  Every time I demo my Trio OB's with the 15" crossover-less full-rangers, and 25ish watts of Decware Torii tube power - I always get a "you're "F'ing" with me look...

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/17/19 at 02:55:11


For those building the large betsy baffles,

Part of the Betsy Baffle sound is the high mass energy drain for the baffle.  That would be the 4 inch thick bass that it bolts to.  That pretty much sets the angle to 90 degrees, and I have found that optimal on both this large baffle and the original Betsy Baffles.   The bass is better at 90 degrees and the rear wave hits the ceiling and the wall at the same time.  As you tilt them back you drop the rear wave to hitting the wall first.

Also the handle at the top is in my experience critical as it braces the weakest part of the panel.  For the big betsy, large cast iron handles are ideal.

Regarding co mass layer damping on the cheap, I have had good success by using a V-Notch Trowel with flooring adhesive which never really hardens.  Just spread it out on the panel and then place 5 O-Rings on the panel in the glue.  That will set the gap so you can lay the second panel down.  Having air gaps between the trowel marks is a bonus so ideally you want the ridge of the glue notch to rise about 1/16 inch above the thickness of the o-rings.

Also, for those who don't know, the mass of each panel should ideally be different.  3/4" - glue - 3/8" - glue - 5/8"  makes a wicked panel that with the thickness of the adhesive /o-rings ends up at a thickness close to 2 inches.

Having said all that for those who want to try it, there is still no guarantee it will sound better than the solid Wenge and Paduke.  The mass is so different that what works for MDF or plywood is likely not going to work the same with ultra stiff and dense hardwoods.  If it turns out when I measure the baffle for vibration that there is a peak or two, It can always be drained away with some solid brass tuned-weights screwed the back.  They would actually be barrel shaped (ironically) just like the baffle. (hint)


So in summary, 90 degrees, don't skimp on the mass of the rear base it bolts to, and the handle.  Got to have one that is stiffer than the wood it is screwed into.

-Steve


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/17/19 at 03:18:06




All I can say is your shop is way too clean so cutting the arcs must have been real messy! ; )

Also, I just love looking at your shop!  I have no doubt that it sounds damn good in there with all that natural diffusion.  It would be nearly impossible to get a listening room in your house that complex as far as wall surfaces go.  I reminds me of my shop in Peoria that at one point had stuff everywhere and it never sounded better.  In fact I was so amazed at the sound it motivated me to clean the shop which I did and that ruined the sound.  Lesson learned there.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 07/17/19 at 05:02:59

Randy,

Do you recall the cutout diameter for the Augie 15" bass drivers you've built?

Cheers,
Jeff

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/17/19 at 06:37:35



Hi Jeff,

The Augie driver fits in the same opening as the Eminence Alpha 15" driver.
According to the specs on the Parts Express website, the recommended size is 13.77".

I just went out to my workshop and checked the template that I used for the Augies and currently use for the Alpha 15 and it is 14".

So ..... I'm thinking that anything between 13.77" and 14" works well.
The baffles I made for you would have been based on my template and the opening should be 14".

The recommended opening for the F15 driver is 355 mm or 13.9764".

Best wishes,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 07/17/19 at 06:40:55

Thanks for the speedy reply Randy!  That is exactly what I was looking for. Much appreciated my friend!! 👍😁

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/17/19 at 06:43:33



Hi Jeff,

I just added some information to my reply .....
Check it again .....

Happy listening,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 07/17/19 at 06:47:25

Lol!  Besides being a super duper OB speaker designer/maker, you are a mind reader! I have a strong suspicion those F15 Lii Audi drivers will sound mighty tasty in those Bubinga baffles you made me. They are heavy and dense as steel!  I was thinking of picking up a pair of F15’s to swap in and give a listen.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/17/19 at 16:48:29

These new speakers are a good reason to attend the Fest this year.

And I have to agree that more weight on the baffles is better.  I still have my big thick MDF baffles I used in iteration #2 of the Palomino Audio project.  Those could be modified to be used with these drivers.

But I hear the call of the dense wood saying, build me, build me.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/18/19 at 04:54:12


Yes, it's going to be a game changer, especially for those with our low power (BIG BALLS) Zen Triode amplifiers... because you finally experience the true performance the amp is capable of.  It's a combination that exceeds sanity on multiple levels.  So, yes, it will be a real treat this year!  It's a good thing I'm not in charge of topping last years fest each and every year, because obviously I couldn't do it, nor could any of us.  This is what the Audio Gods wanted you and me to hear, so come and hear it.


The density thing... African Paduke Janka hardness: 1970,  Wenge is : 1930, however the wedge is twice as hard to cut and feels twice as heavy???

Some interesting specs on Wenge
Average Dried Weight: 54 lbs/ft3 (870 kg/m3)
Specific Gravity (Basic, 12% MC): .72, .87
Janka Hardness: 1,930 lbf (8,600 N)
Modulus of Rupture: 21,990 lbf/in2 (151.7 MPa)
Elastic Modulus: 2,550,000 lbf/in2 (17.59 GPa)


Same specs of African Paduke

Average Dried Weight: 47 lbs/ft3 (745 kg/m3)
Specific Gravity (Basic, 12% MC): .61, .75
Janka Hardness: 1,970 lbf (8,760 N)
Modulus of Rupture: 16,830 lbf/in2 (116.0 MPa)
Elastic Modulus: 1,700,000 lbf/in2 (11.72 GPa)


Steve

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/18/19 at 12:14:27

I priced out the wood.  That isn't going to happen.  Especially with my meager wood skills.  It would likely end up an expensive pile of kindling.

I will seek out substitutes such as the butcher block suggested above.  I asked for a quote from a local counter top manufacturer.  42X36X1.75 I think is what I asked for.

Are there any less exotic woods with decent density and weight?

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/18/19 at 15:32:59

An interesting material, if density is a major consideration, is the man-made "quartz" slab that's used for countertops.  This is a combination of stone and resin.  3 cm is readily available but beware, it's heavy as granite.  It seems to be fairly "dead" to vibration -- more like dense wood than stone.  Of course, you'd have to get with a fabricator since cutting and polishing takes special tools.

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 07/18/19 at 15:49:36

When I was at T.H.E. SHOW high-end audio event in Long Beach a couple months ago, there was a speaker manufacturer that builds their entire speaker cabinets out of granite.  They were tanks!  They sounded really good and when I placed my hand on the granite cabinets, they were dead to vibration at a fairly high listening levels.  

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 07/18/19 at 15:53:56

Pal,
Here is a Janka hardness list for reference:  https://en.wikipedia.org/wiki/Janka_hardness_test

The Bubinga Randy used in my Caintuck bass baffles is 1980 on the scale!  

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/18/19 at 16:00:00



Steve's most recent posts reminded me that when I first started making the Betsy baffles a few years ago that there was an abundance of hardwood slabs from one of my suppliers that were 18" wide and 3/4" thick ..... almost any species I wanted.
They shipped them to me finished on all four edges and only needed fine sanding before applying a finish.

Sadly, that supply has dried up and I can rarely find anything decent in an 18" width .....

It seems that the majority of the big trees are being milled in very thick pieces for custom work and are priced accordingly.

That is why I started offering the two-tone baffles.

Here is a photo of a solid 18" wide Wenge baffle.



Larger photo here.

The grain on these baffles was amazing and I was totally shocked when I applied the linseed oil / beeswax finish.
They became as black as a bowling ball .....

I don't even remember who purchased them ..... but whoever it was has a very special and unique pair of Betsy baffles .....

Were the baffles heavy ? Yep .....

Randy


Title: Re: Steve's BIG BETSY Project
Post by Lon on 07/18/19 at 17:31:34

Randy,

Wenge is an excellent tone wood that some luthiers use despite the difficulty to work with. It imparts a rich and precise tone. I have a wenge neck and fingerboard on one of my favorite guitars, and one of my favorite basses (they both have black limbs bodies, I find the combination of these woods excellent).

The guitar:

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/18/19 at 20:16:01



Hi Lon,

Very cool .....

Nice looking guitar .... and I'm betting that it sounds wonderful.

Best wishes,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/18/19 at 20:24:41


Update .....

Jeff,
The F15 drivers came in today and Lii Audio's tape measure must be slightly different than mine. The opening in my template is a full 14" as well as the opening in the baffles I mounted them in.
Very tight fit ..... actually a little small ..... at least for the pair they shipped to me.
I'm thinking that 14 1/8" might be better .....

If you decide to buy a pair and mount them in your Bubinga baffles, you will probably have to slightly enlarge the cutout.

Just a heads up .....

Best wishes,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/18/19 at 20:29:27

Thanks Randy.  I’ll pick up some sandpaper :)

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/18/19 at 20:45:39



Well ..... here we go .....







Larger photos here, here and here.

At this point, I will only say that I can only guess what Steve is hearing with the BIG BAFFLES and the 25th Anniversary amp.

The more surface area a baffle has, the more bass it will make.

Good grief .....

Randy


Title: Re: Steve's BIG BETSY Project
Post by Geno on 07/18/19 at 20:50:47

Randy,

Initial impressions?

Thanks,

Geno

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/18/19 at 20:54:45



Hi Geno,

Still trying to wrap my head (and ears) around what I am hearing.
The drivers have zero break in time, but what I'm hearing so far is positive.

Stay tuned.

Best wishes,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Lon on 07/18/19 at 21:00:52


Randy in Caintuck wrote on 07/18/19 at 20:16:01:
Hi Lon,

Very cool .....

Nice looking guitar .... and I'm betting that it sounds wonderful.

Best wishes,
Randy

It does sound good. I have it set up with two Seymour Duncan "Cool Rail" and one "Hot Rail" "stacked" humbuckers which can also be each switched to single-coil, and instead of a volume and two tone controls, I have three volume controls and even a phase switch. So many possible sounds, and I get great jazz and blues sounds . . . it's like several guitars in one.

Congrats on that new driver, looks as if it's going to be a great option.

Title: Re: Steve's BIG BETSY Project
Post by Brian on 07/19/19 at 05:24:20

Palomino asked:  "Are there any less exotic woods with decent density and weight?"

American oak in White, Red, Pin or Live varieties would be heavy and hard. Live oak always seemed the densest to me.  Red is probably the most porous.


Brian

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/19/19 at 17:19:45

Randy,

The first few days the tightness is distracting.  They do loosen up with time.  Also the efficiency is disarming.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/19/19 at 17:25:54


Another thing that happens with the big baffles that doesn't happen with the small ones is that the visual of the baffle is so overpowering it is a mind melter as your brain tries to connect the sound to the speakers.  I have to close my eyes with these big baffles and when I do, I can not tell where they are.  Even in Randys smaller room, the same would be true.



Title: Re: Steve's BIG BETSY Project
Post by Dana on 07/19/19 at 17:28:30

For the adventurous in the Seattle area.  They are only 37" tall ....

https://seconduse.com/inventory/items/708091-S/resawn-white-oak/

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/19/19 at 17:35:10


As far as alternate approaches using hardwoods, there is no reason why a person couldn't cut 3/4 boards into 1-3/4 or 2 inch strips and glue them together to create the baffles. Oak would be a great wood for it and by gluing it up from strips you would have a nice quarter-sawn look.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/19/19 at 17:42:27


This is where I get my exotic lumber.  I add 2.00 a BF to have it shipped to my door.

https://crlumber.com

Steve

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/19/19 at 20:16:12

In the Chicago area we have Owl hardwoods.  I'm like a kid in a candy store there.  All kinds of exotics.  Huge tree slabs.  Butcher block, you name it.

They do 1-2 cuts for free and a buck a cut after that.  Precision cuts for sure.

They make stuff too.  I had them make me a maple mantle to match my family room floating shelves (which I made) and the maple cabinets.

I am going to put these drivers in my MDF Palomino Audio project baffles that are just sitting around to run them in.  Then I'll decide on my next course of action once I see how I like them.

Title: Re: Steve's BIG BETSY Project
Post by lazb on 07/19/19 at 20:25:38

Man, Pal, I am envious! Seems so many are jumping on the Big Betsy bandwagon. Lii Audio best get busy making more drivers. Sure wish I could jump in but, for now, gonna be happy with my DNA2s. At least until DECFEST!

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/19/19 at 20:46:40

Yeah, it was a bit of an impulse buy, but Steve's enthusiasm and my desire to get back to a single driver cross-over less design plus the price led to me pulling the trigger.

I usually wait for others to try and/or ponder my purchases for months.

I really like my speakers right now.  I will likely try some new bass drivers but other than that, I think the PAP has run its course.  They are a bit franken-speakers though, and thus my interest in these drivers.  Simplify.

I have exchanged a few emails with Leo from Lii.  Seems like a decent chap.  He is interested in attending Decfest.  That could be fun.

Title: Re: Steve's BIG BETSY Project
Post by lazb on 07/19/19 at 21:01:26

Yeah, sounds fun! Be a lot farther "drive" for him than me! LOL

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/20/19 at 00:39:26

I did inventory on surplus butcher block tops I've salvaged from jobs and with a couple of glue-ups I can easily get blanks big enough to cut a pair of these baffles.  My stock is 1 1/2 inches thick and hardrock maple.  Worth the effort and $450 for the drivers?

As always, Steve's enthusiasm is infectious!

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/20/19 at 04:05:16

Time will tell...

I’ll see how the 1.5” MDF sounds.  The drivers will be a little low to the ground but I am hoping I can get an idea of the sound and if I like it enough I’ll figure out my hardwood strategy.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/20/19 at 06:27:31


It is exciting to know this is all going to transpire into a great conversation as everyone gets them built and begins to compare notes !

This weekend I am going to restore the baffles to their original idea which was to use the vintage Alnico Utah drivers in parallel with the matching Alnico Betsy Baffles.  I'll take some pictures. and report the results.  The first time I did this was the best imaging I ever got, and wonderful timbre with great low-bass and reduced mid-bass which really opened up the sound like a spacious venue instead of an in-your-face 1st row experience.

Tonight I am listening to them with the F15 drivers on the 25th Anniversary Zen Triode amplifier, and it is making me realize that none of us really know what the drivers sound like!  I mean, I have been listening to them for the past two days with many different amplifiers, and when I got the UFO25 back in it was like a welcome friend! So then I decided to change the input tube from the supplied 7DJ8 to the warmer 6N5P, and in my room it made the speakers sound more like you would imagine 15 inch drivers would sound like.  Slower, warmer, thicker...  This alone made enough of a change that I no longer loved the speakers in such a supportive way.  In a harder room, it would have been glorious.  So, thank God for DECFEST every year, because it gives everyone who attends in person and everyone who listens in on the live broadcast a real good baseline of how I'm referencing the sound of these speakers.

Obviously being a touch rolled they are going to like a higher grade NOS tube because those tubes have greater focus, speed, and dynamics.  This all helps the 15 inch driver sound more like a smaller driver with greater speed.








Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/20/19 at 13:05:55

For me, getting a new pair of drivers offers an opportunity to start over and figure it out.  Saying these hold promise is like handing me a new puzzle.  I already have my “design” spreadsheet going.

The info on the tubes gives me a place to start. Thanks.

My goal would be to provide some feedback on how MDF sounds.  I can also put them in 3/4 and 1.5” Baltic birch.  Each of these are around 32-34” wide.  The catch is none of them are the Betsy Baffle shape and the driver is only going to be 6” or so off the ground.  So I don’t know how valid my findings will be.  But if I can get them to sound decent in one of these configurations it will point the way to the next step.

Getting the 25th presented a similar puzzle.  I changed tubes, ICs, speaker wire and even modified my drivers in my OBs. All great fun and when I got there, it was magnificent.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/20/19 at 16:00:00

Palo,
It sounds like you need to make some sort of risers to get the driver up off of the floor. I'm thinking something with "wings" Perhaps with the curves cut on them. Like a "H" frame that raises everything up 16" or so.
Just spitballing here.
Get me the sizes of what you have now and I'll have my new apprentice draw it up.  

Title: Re: Steve's BIG BETSY Project
Post by will on 07/20/19 at 17:15:01

With a smallish room area for speakers, I am looking forward to reports of smaller versions of Randy's baffle shape. Looking forward to your reports Randy using the F15s in your normal baffle. Also has anyone thought of doing a pair with the same baffle proportions, but between Steve's and Randy's in size?




Title: Re: Steve's BIG BETSY Project
Post by Geno on 07/20/19 at 17:49:05

All you gents try to keep in mind what Steve labeled, Randy’s “Sacred Geometry” when designing your baffles. For whatever the reason, the barrel shape, with the driver a lower height from the ground, works. That is why Steve made Big Bertha to scale. There are mystical forces at work here. I really think that, and it makes sense with all Steve’s talk of UFO’s, that Steve and Randy are both aliens. How else can you explain such an off the wall design having these results ;D

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/20/19 at 18:26:11

This is what I have to work with:



22 3/4" wide

25 " from the floor to the bottom of the upper driver hole.  There is about 6" from the top of the bass driver hole to the bottom of the top driver hole.  I would cut them off below the top driver to have the same space above and below the bass driver cutout.  

4" from the floor to the cutout for the bottom driver.  Maybe an inch or two probably to where the driver starts (the 15A driver is 6").  I'd have to look at the 15F spec sheet to see what this distance is.

I would probably take off the back "foot" and do something else for the supports.  I have some nice 4X4 oak table legs that a friend in the office furniture business gave me that I might be able to use for the supports.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/20/19 at 18:51:12

Palo,
Project one this Monday morning will be a discussion with my design guys on how we can modify what you have to end up with what Steve has.
Believe it or not this isn't that far off of what we do every day, take something that we already have and modify it into something that we need. Though working in MDF is way easier than 2" thick steel.

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/20/19 at 19:33:49




Quote:
I really think that, and it makes sense with all Steve’s talk of UFO’s, that Steve and Randy are both aliens. How else can you explain such an off the wall design having these results .....


   


Title: Re: Steve's BIG BETSY Project
Post by Geno on 07/20/19 at 22:16:53

;) ;) ;)

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/20/19 at 23:47:22

Looking over the LII Audio site, any reason their Crystal-10 wouldn't be a better choice than the F-15?  And maybe scaling down the baffle some?

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/21/19 at 00:14:29

Just the cost.  It seems to dig a little deeper actually.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/21/19 at 01:00:51

I can't interpret the spec's but the graph looks like it extends in both Hi's and Low's but gets as loud.  If I make something I'd like it to equal or beat my HR1s in sound but get MUCH louder.  

One other thing, if it's still on, the Crystal-10s ship with a free pair of F-15s.

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/21/19 at 03:35:27



After living with the F15 drivers in a pair of my low boy baffles for a couple of days, I'm ready to share a few thoughts .....

Since this thread is primarily about Steve's BIG BETSY Project, I thought it best to post my thoughts in the forum Steve has generously created for the Caintuck Audio products.

If you wish to read them ..... they can be found here.

Happy listening,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/21/19 at 06:46:33



Quote:
I can't interpret the spec's but the graph looks like it extends in both Hi's and Low's but gets as loud. If I make something I'd like it to equal or beat my HR1s in sound but get MUCH louder.  


I noticed this as well but what the specs don't convey is the bass slam of this larger driver. It has 325 HP and 795 FP of torque.  My guess is the 10 inch drivers will have 600 HP and 500 FP of torque.  Both will be great but the brute force of muscle has been proven since the 1950's as legendary for a reason.

Nevertheless I have a feeling before it's over we will find out what the differences actually are. Presently if I compare the Alnico Betsy Drivers with the F15, the Betsy are way faster and a lot more extended but lack mid-bass and low-bass by comparison. Probably the 10 inch drivers from Lii-Audio are going to have a nice balance of both which could eliminate my original Array.  Although the original array featuring the Big Betsy baffle is always going to be unbeatable because of the giant scale it has and the low bass performance combined with the finest of the alnico Betsy drivers I suspect may be hard to beat.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/21/19 at 17:29:43

Well, I might have to see if LII's promotion is still on and get both!  One advantage to the 10" is a smaller baffle.  I would like to get efficiency well above the HR1s though.  Is there any way to calculate or predict efficiency from the spec'd numbers?

The horsepower/torque analogy is helpful but how does the lower extension spec tie in?  Do the 10" just go into a region that isn't needed?

BTW, lately my HR1 bass is amazing.  It may be the music I'm currently favoring but I am consistantly getting deep rumblings that I feel in my chest.  I think Ziggy's mods are a big factor.  They seem way better than anything I remember pre-mod.  One thing though is that I'm listening just about as high as I can go with my meters starting to jump.  I'd like more volume.

Title: Re: Steve's BIG BETSY Project
Post by ScottNC on 07/21/19 at 19:37:12

I have to say between this and Randy’s thread these have me wanting to hear more and more how it all progresses.
I too also hope they will be offered in some form for those of us without a shop (and skills🤗) needed to build these on out own. I can’t get the visual of Steve’s build gone from my head...
Thanks to all, it’s a great read.
Best,
Scott

Title: Re: Steve's BIG BETSY Project
Post by Rivieraranch on 07/21/19 at 21:13:58

Seems that the evolution of speaker design at Decware went from MTM then to radial and now large driver open baffle. Fascinating journey. With all this buzz about 10 inch drivers, 15 inch, thickness of the wood, etc., something mighty profound is bound to result.

Title: Re: Steve's BIG BETSY Project
Post by will on 07/21/19 at 21:35:37

I have been thinking along the same lines Archie, perhaps a smaller baffle with a 10" driver. Don't know, but for my needs, I am guessing better top extension may be more important than bass slam. My Torii, not maxed out with tubes, I would welcome a little more headroom in my room also, but it is sounding so incredible, I am not willing to jack it up with VRs and hotter inputs and power tubes. I can't quite imagine 99 dB speakers!

Fun thread!

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/22/19 at 00:46:05

UPDATE 7/21/19

As promised, and update about the Big Betsy Baffles set up in my originally intended array.

First here is another picture of the F15 from the back.  Note the F15 is actually grey in color, this pair I carefully changed the color to black.



Steve


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/22/19 at 00:48:07


This is what they look like tipped back as I prepare to remove the F15 drivers.



I have some ultra great spikes, super heavy duty with balls on the points, but sadly if I install them no-one will be able to move the speakers during DECFEST.  As they are, they slide around fairly easily on the carpet.

Steve


Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/22/19 at 00:51:51

I'm trying to figure out what some of these driver spec's mean and I found this site that has some useful information.

https://www.eminence.com/support/understanding-loudspeaker-data/

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/22/19 at 00:53:09


Here they are with the drivers removed, good opportunity to apply some Black Bison wax.



I was polishing them by hand for a long time despite possessing the knowledge that I had a buffer somewhere. What's wrong with me? My arm hurts.  


Steve

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/22/19 at 00:54:42

Steve, those baffles are really pretty.  I especially like that you used linseed oil on them.  I'm thinking though that the oak could use a few coats of black satin paint.

And thank you for that good front picture with and without the driver installed.  How important is the recess?  Randy doesn't seem to recess his Betsys.  (Or does he?)

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/22/19 at 01:17:58


Here are the vintage alnico Seeburg DDS1 drivers installed.



If I had less speakers in the room, I would spread this out a little wider, however the imaging is wall to wall...
so maybe not.

Steve


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/22/19 at 01:31:47




Here is a rear view of the complex crossover and wiring used for my array.  If you want the sound to be warm and a touch fat wire the speakers in phase.  If you want no overlap and to simply extended the bass of the Betsy Alnico speakers, then wiring is done out of phase.  That is to say the small Betsy and the big Betsy are wired as a pair either in-phase or out-of-phase.  The imaging is in the category of best I ever heard with this particular out-of-phase arrangement.  The sound stage is perfect and huge.  You are in row 10 or 20 depending on the size of the venue when recorded.

The integration between these two drivers is so perfect you would never know it was two drivers.

Sadly I won't be demoing this array approach at DECFEST because changing out drivers in the baffles during the fest is just asking for trouble.  The F15 drivers will be what we demo the Big Betsy Baffles with.

Title: Re: Steve's BIG BETSY Project
Post by will on 07/22/19 at 01:46:10

Beautiful, and a nice easy "crossover!" Congratulations Steve! I bet the combination is gorgeous.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/22/19 at 02:18:52

The four Betsy array from the sitting position.



Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/22/19 at 02:20:28


And another shot from the listening position.



I would have to say the imaging of this array is actually better than my personal record holder - the egg speakers.  

Steve

Title: Re: Steve's BIG BETSY Project
Post by Brian on 07/22/19 at 02:24:45

I sure like the glow and shine the wax is presenting.

Brian

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/22/19 at 02:49:44


Yes, there is something to a natural hand-rubbed finish that you just don't get any other way.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/22/19 at 02:56:32


To quote myself:


Quote:
Sadly I won't be demoing this array approach at DECFEST because changing out drivers in the baffles during the fest is just asking for trouble.  The F15 drivers will be what we demo the Big Betsy Baffles with.


Damnit. If you were here right now listening to this you would never forgive me for not letting anyone hear it.  It is so flawless on literally every level it checks all the boxes.  The disappearing act is just too much to deal with.  The resolution is insane.  Timbre and every other aspect is so right that it probably needs to be heard.  

Warning, if I do set up this array, and you look at the four baffles and try to figure out where the sound is coming from, your eyes will fall out on the floor and roll under the couch... so Just don't do it.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/22/19 at 03:28:13


Here is an image of the Big Betsy Baffle array - of what I see when I close my eyes. This is literally no exaggeration. This is what I tend to like in a speaker/amplifier combination... being transported to the venue - like being in a time machine hearing/seeing it as it was recorded...  This image represent my EXACT soundstage, width, hight, depth and overall space.



You can superimpose the image above over the image below.

I'm happy to report that this array and the SE84UFO25 perfectly recreates the above image as though it was on a Startrek Holodeck... but then when you open your eyes everything shrinks 100 times and you see a pair of big speakers right in front of your face in a small little carpeted room.  



quick, close your eyes!




This is by far the best visual explanation of my soundstage that I've ever come up with.  Eyes shut... eyes open... eyes shut again!

Am I blowing smoke up your ass you wonder?  Definitely not.  If the bulk of audiophiles today knew this was actually possible... it would lead to quickly achieving this sound and resolution which would quickly lead to happiness.  I'll probably have this set up until October so if you don't believe me, drive or fly over for a personal listening session and tell everyone here how accurate this image really was.

God I love good sound!

Happy listening,

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/22/19 at 04:01:56


Here, I did it.  I superimposed the two images.  This is what I am hearing with this array.



Notice how the listening chair is a balcony seat?  My carpet becomes the edge of the balcony.  You would never want to record on the floor level because all the different instruments would stack behind each other and become a big blur of sound.  From the balcony you can pin-point every sound in space without one ever overlapping the others.  It is perfect clarity.  If the recording was done with two microphones, as all the best ones are, this is how you will hear it.  It is the reference for soundstage reproduction during playback.

See how the small Betsys are nestled in where the bulk of the instruments are, and the big Betsys are reproducing the bigger sounds coming off the walls in the music hall.  It's a near perfect room set up if you want to reproduce sound from this perspective which has always been my goal because believe me, if you can get this to happen, all other recorded music will sound good...no problem.

In contrast, the F15 puts you about 15 feet in front of the grand piano in this same image.  Basically you are nearly on stage by comparison.  That is also pretty thrilling but completely different from this.  This is perspective listening, that is intimate listening or perhaps participatory listening.  Two alter egos of music reproduction.




Here is a smaller image that fits in the frame here without sideways scrolling.



My beautiful listening room as I hear and see it with the lights low.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/22/19 at 05:01:20


And as I said the ability to do that makes it possible to do any recorded music with uncanny intricacy.  But this is not an imaging thing as I make it out to be but a combination of perfect frequency balance, speed in all the right places, and timbre that make the illusion possible.

Right now I am listening to 'Sweet Pain' Nusrat Fateh Ali Khan & Michael Brook - Night Song' and I have never heard anything sound so real.  It's like just because I owned this recording doesn't mean I've ever actually heard it... but now, holy crap!  I had a real suspicion when I got past the first few hours of the Betsy Alnico drivers in my Betsy Baffles that something great was going to happen.  If just a way to add some lower end scale to it, I thought.  It would become a new reference I thought... and trust me it has.  Just insane.  It just sounds so real.  Also I am only using the SE84UFO25 by itself being fed from the ZTPRE and a good DAC.


Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/22/19 at 15:31:59

Holy crap Batman!   ;D  I just had to say it.  It's Steve's catchphrase.   ;)



I've been in communication with LII Audio regarding their Crystal-10 vs their F-15.  This is what they had to say:


Quote:
As for the bass slam, honestly, F-15, for its size, do a little better. Crystal-10 is a different style, its mid and high are super sweet and exquisite, especially when you play a track of female voice, Leon who designed Leonidas XO of pure audio project said it's "to die for". For Crystal-10, the bass is OK as most people said, but not rocking.

Besides, Crystal-10 is more sensitive to enclosure than F-15, we recommend enclosed box with at least 220L capacity to give it space to perform well, I personally did some experiments, different boxes can make great differences to this driver.


Since we are discussing open baffles here, I think this driver is out of contention and I'm back to building HUGE baffles.   :-/

Title: Re: Steve's BIG BETSY Project
Post by Geno on 07/22/19 at 15:49:15

And you'll save a shitload of money to boot!

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/22/19 at 16:13:01




Quote:
How important is the recess?  Randy doesn't seem to recess his Betsys.  (Or does he?)


Hi Archie,

No, I do not.
The hardwood on my baffles is about 3/4" thick after processing.
If I recessed the driver, there would only be about 1/2" of material behind the driver and the screws I would have to use would not be long enough to secure the drivers properly, in my opinion. I also don't want to take the chance of cracking or splitting the narrow center section of wood on the two tone hardwood baffles because of it being too thin.

The packaging materials I use have to accommodate the 3/4" plywood that I use for the less expensive speakers, so I just make the two tone hardwood version 3/4" thick as well.

For what it's worth, I did build a pair with recessed drivers and did an A / B with a stock pair. I could hear no sonic difference.

The surface mounted drivers look fine to me from the listening seat, so I never gave it any additional thought.

Best wishes,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/22/19 at 16:22:46

Thanks Randy.  I wasn't sure since one of Steve's pictures seemed to show your's recessed.  I prefer the look of the surface mount and if there is no sonic benefit from recessing then I'll save myself the extra step.  I'm also considering gluing up the panel (center-ish joint) after running through a bandsaw to avoid cutting the big arc with a router.  Clamping against the curved edge of the pieces gives me some hesitation though.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/22/19 at 16:54:16

I guess I'm committed to building a pair of the mega Betsy's as I just ordered a set of drivers.   :P

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/22/19 at 16:58:57

Mine are shipped but I am not sure of the delivery date.  My issue is I am out of town the next two weekends so an early results won't be available for a while.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/22/19 at 17:07:51

Drawings are in process!
I hope to have a pretty good looking drawing of the Big Betsy's this afternoon.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/22/19 at 17:11:00

Now I've got to get out to my shop and get organized to handle these big pieces.  Making them out of large BB blanks will really help the process along.  I'm using Steve's drawing and a design-as-you-go process.

For anyone who hasn't explored the LII Audio site, they sell a very interesting speaker that uses their Crystal-10 driver.  They look surprisingly affordable too given the geometry and what they charge for the drivers alone.  Maybe someone in California can demo them?  (They have a couple pair in a warehouse there.)

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/22/19 at 17:13:43

Very cool Donnie.  We should soon know of the sound from big, mid and original besty sized baffles.

I have to figure out the best way to draw/cut the arc.  I have a new router but may do some freehanding.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/22/19 at 17:30:54

Any good ways to cut the driver opening?  I'd like to use a router with a guide bushing but I don't know how to make the template.  I can cut perfect circles on my bandsaw but not an inside circle.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/22/19 at 17:44:23

I use one of these for inside and outside holes and radii.
https://www.lowes.com/pd/Milescraft-CircleGuideKit/1000233663

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/22/19 at 18:06:02

Parts Express also sells a jasper jig specifically for speakers.  

I just made one out of Plexiglas.  

I have also seen one made with a thin board.  Pin hole and then a hole for your router bit (make them 1/2 your driver cutout distance apart).  I made my pin out of an old broken drill bit.

I always cut a blank and test using an old piece of wood before I try it on the expensive stuff.

Title: Re: Steve's BIG BETSY Project
Post by TomR on 07/22/19 at 18:47:30

Just a nube here.... where do you purchase the Betsy alinco drivers ?


Tom in Lafayette

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/22/19 at 18:58:30

Local price (Chicago) on made to order maple butcher block (pickup only).

42" x 32" x 1.5" w/poly finish - $300ea

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/22/19 at 19:03:15

I think just contact them and ask:

http://www.wildburroaudio.com/contact.php

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/22/19 at 19:07:27




Quote:
Just a nube here.... where do you purchase the Betsy alinco drivers ?


Hi Tom,

Palomino is correct .....

My arrangement with Wild Burro Audio Labs does not permit me to sell the raw drivers ..... only if they are installed in my Betsy baffles.

You can contact Douglas at :

http://www.wildburroaudio.com/contact.php

Best wishes,
Randy


Title: Re: Steve's BIG BETSY Project
Post by dank on 07/22/19 at 20:54:33

Circles with a router:
https://www.parts-express.com/jasper-circle-jig-model-200--365-250
Been using it for years, works great.  Diameter from about 2" to 19" in 1/16" increments.  Only down side is you pin in the exact center, so once you've cut a circle you can't cut a larger one (without gluing the cutout back in - which I've done on occation).

Title: Re: Steve's BIG BETSY Project
Post by TomR on 07/22/19 at 21:13:23

Thanks for the Betsy sourcing information


Tom in Lafayette

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/22/19 at 21:30:57

I need to figure out the jig for the sides.  I’ll just make a board jig.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/22/19 at 22:23:52

Here is the Big Betsy print that my guy did today.
I hope that it helps someone.


Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/23/19 at 01:21:53

Those are good circle jig suggestions.  However, now that I'm into the project I'm determined to spend a little as possible.  So far I have the baffles cut (but not smoothed) and my cost is "0" since everything was already in my shop.  I think I'll cut a circle on my band saw and then make the negative template using my router and a guide bushing.

One thing I did wrong was I didn't see the top and bottom dimension and I used Steve's "sacred Geometry" of R=42".  I missed the "around 42 inches" in his early post.  So mine have a top and bottom around 21 1/2".  Mine truly are sacred geometrically correct!   ::)

Since I had to glue up my panels from two pieces of butcher block, I went ahead and cut the radii on my bandsaw.  I'll do like Randy said he does and clamp the baffles together and belt-sand the edges smooth.

What driver hole diameter is everyone using?  I saw that Randy thought 14 1/8" might be good.  I'd like as small an opening as possible to leave plenty of meat for the screws.

These baffles made out of 1 1/2" maple are beasts to move.  I can't imagine how Steve maneuvered his around his shop given how much more they must weigh.  Once the bases are on I might be using a hand truck.

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/23/19 at 02:30:34




Quote:
What driver hole diameter is everyone using?  I saw that Randy thought 14 1/8" might be good.  I'd like as small an opening as possible to leave plenty of meat for the screws.


Hi Archie,

I made a template with an opening of 14 1/8" and the F15 driver fit in it with a little bit of play ..... you might be able to get by with 14 1/16".

From what I read on the Lii Audio website, it looks like the spec for the driver opening is 355 mm.



If that is correct, my conversion table makes that 13.9764".
The template that I have been using for the Hawthorne Audio Augie 15" driver and the Eminence Alpha 15" driver is 14" exactly.
The F15 driver would not sit flat in that template .....

I'm hoping that Steve will weigh in on this.
It's possible that the baskets on my pair have a slight anomaly, but I don't think so ..... neither one would sit flat in my 14" template.

Happy listening,
Randy


Title: Re: Steve's BIG BETSY Project
Post by dank on 07/23/19 at 12:48:05

Mine fit just right in a 14" cutout

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/23/19 at 13:49:30

Measured mine and it’s 14 1/8”.  Drivers due to arrive Friday but I will be in Michigan for the weekend >:(

Title: Re: Steve's BIG BETSY Project
Post by dank on 07/23/19 at 14:22:10

Big baffles:  Something's not adding up -

Steve's drawing and Donnie's show the big baffles as being 32.66" wide at the widest point and 20.56" wide at the top and bottom.  This should correspond to a 42" height and a 42" radius cut on the outer arc's (but I lack the mathematical skills to verify this radius cut measurement).  Donnie's drawing shows this is a 39.6" radius cut, which is way off from 42".

But Steve's drawing also shows the widths of the boards used:  7.22" (outer wenge), 8.39" (inner paduke), and 3.81 (center wenge).  If the 3 middle board widths are added up you get 8.39 + 3.81 + 8.39 = 20.59" which is wider than the baffle width at the top and bottom.  This leaves nothing for the outer board's width at the top and bottom which is clearly wrong, as can be seen in the pictures.  So, are the board width's the pre-planed widths and have nothing to do with their final size, or are the top and widest width measurements off?

Unfortunately, I went with the board sizes and came up with 35" wide at the widest point, and then measured / guessed / interpolated the width of the two outer boards at the bottom from the photo and came up with 24" wide at top and bottom.  This turned out to be a 43" radius cut which I thought was "close enough".

However, while sounding very interesting and different from other speakers, (my first impression was "holy crap, I need to get a bigger room") I am definitely NOT getting the bass and bass slam that Steve has been talking about.  I may need to trim my arch's a bit.

Randy - what are your original baffle's width measurements at the top and the widest point and the height measurement?



Dan

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/23/19 at 15:08:33

I had another idea to get closer to the weight and density of the Steve's big baffles.

I looked up 42" oak stair treads at Owl Hardware.  They are 11.5" wide and 1" thick.  Called and the cost is around $26 each.

I would have them trim a little more than 1/2" or so off each one, removing the rounded portion of the tread and glue them together.  $80 for each baffle or double them up for $160 per baffle.  Not exact, but pretty close.

I was at home depot and while they didn't have 42", they did have 36", which I lifted and thought, man, even at 1" it will be pretty tough to lift/move these.

I'd still have to figure out the stands, but I can probably do something with the oak 4X4 table legs I have.

Just an idea.  To do butcher block in Oak at similar dimensions (but the correct thickness) would be $660 vs $160 (single) or $320 (doubled up) for the treads.

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/23/19 at 16:02:03




Quote:
Randy - what are your original baffle's width measurements at the top and the widest point and the height measurement?


Sorry dank ..... that's a trade secret .....



My baffles are 22.5" tall x 17.75" wide at the center.
The top and bottom width is 11".

Best wishes,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/23/19 at 17:05:24

Depending what scale factor is used, the numbers will be different.  I'm guessing Steve used 15/8=1.875 but the numbers don't match exactly (using Randy's panel dimensions).  Donnie's radius has to be too tight though.  I was very careful in laying out my arch and with a 32 3/4" width (like Steve) and a 42" radius, I ended up with 21 1/2" top and bottom.  It wouldn't take much to bring that down 1/2" per side.  Maybe R=41 1/2"?

I have a hard time believing that the exact shape is highly sensitive and critical.  I would assume that baffle material is more important.  MDF might be too damped compared to hardwood.

I posted a link earlier and I'll post it again.  This BB is 1 3/4" thick, made in the US and can be had for $625/pr delivered.  The only drawback is that the pieces are finger jointed (looks mostly).  Maple is denser than oak and there is much less fussing with glue-ups.  https://www.foodservicedirect.com/john-boos-oil-finish-hard-rock-maple-industrial-top-48-x-34-x-1-75-inch-1-each-21369953.html

I've seen affordable BB in Lab Supply catalogues and the like.  If I were to start from scratch I might buy wider hard maple and make my own panels.  The only problem I generally find is that with panels this wide I'd have to go find a shop and buy some time on their Timesaver to sand and flatten.

If the driver opening is a bit tight, will a slight chamfer take care of it?  I might shoot for 14" if that's the case.

Oh, and based on the UPS Tracking Number I received from LII Audio, I am guessing they have a US warehouse that they are shipping from.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/23/19 at 17:12:28

My numbers are what the software came up with.
It may be wrong, it may be right.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/23/19 at 17:15:58

I figured that.  You are probably right then.  So much for Steve's Sacred Geometry!   ;D

I might lean on my belt sander a bit near the ends.

Title: Re: Steve's BIG BETSY Project
Post by dank on 07/23/19 at 18:23:53

I found a pretty cool arc calculator on line

https://www.mathopenref.com/arcradius.html

that confirms Donnie's radius of 39.6 (it implies 39.36).

Scaling Randy's numbers up to a 42" height yields 33.13" at widest point, and 20.53" wide at top and bottom/  These numbers imply a radius of 38.15".  So I probably need to run my baffles thru the router again...at least my mistake made then too big instead of too small.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/23/19 at 22:42:06

I can't imagine that a small difference in a radius that large is going to really matter for sound quality. But I'm often wrong.
In my world if you are right 75% of the time they think that there is some sort of black magic going on.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/24/19 at 00:39:30

No way was I going to recut my baffles for a half inch per side at the tops and bottoms.  I'm not even sure linear scaling of Randy's baffle relative to the driver is completely logical.  We all will have differences one way or another.  Heck, Randy isn't even making his baffle bigger for the F15.

Today I smoothed the edges, cut notches for my footers and cut the driver holes.  This was a full day!  Moving these monsters around and making jigs takes a lot of time.  When Steve starts selling them don't be surprised at the price.  They are a bear to make despite their simplicity.

BTW, removing 14"D by 1 1/2" thick maple blanks lightened things up considerably.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/24/19 at 01:13:07

I don’t think I would recut either.

I used Donnie’s drawing to figure out how to cut my old baffles.  They aren’t tall enough to do the magic dimensions.  So I am going to make a couple of low boys.  I still intend to cut the radius (figured that one out today) but that’s about it.  Slap a little duratex on it and call it a day.

At 1.5 inches of good quality MDF we’ll see how that sounds and then take it from there.

Title: Re: Steve's BIG BETSY Project
Post by beowulf on 07/24/19 at 01:19:22


Palomino wrote on 07/23/19 at 15:08:33:
I'd still have to figure out the stands, but I can probably do something with the oak 4X4 table legs I have.


Have you seen the stands on the new Spatial Audio X Class?  Something like this would look pretty cool.






Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/24/19 at 17:04:13

Pal, it will be interesting to share impressions once we all get our's up and running.  I've got a theory that MDF might be over-damped compared to solid wood or plywood.  Or it could be my prejudice since I hate the stuff.   ::)

Title: Re: Steve's BIG BETSY Project
Post by lazb on 07/24/19 at 17:10:21

Archie, my use of MDF is limited to "just enough to know I do not like it" but I wonder if the OSB (oriented strand board) might be of some use as a replacement?

Title: Re: Steve's BIG BETSY Project
Post by Lonely Raven on 07/24/19 at 18:12:05


FF to about 28 minutes in this video.

https://www.youtube.com/watch?v=EEh01PX-q9I

This guy is a great teacher.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/24/19 at 19:18:50

Arch, I transitioned from MDF to Baltic Birch for my OBs because I felt the Baltic had a better, more lively sound.  

My initial test for these new drivers will be in MDF because I hadn’t cut up the old baffles and burned them yet.  Not a fan of mdf but use it some times.

Last night I cut them down and put a little paint on them so the low boys are ready to go. In essence they are the same height of Randy’s but about 5 inches wider.  A lot heavier.

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/24/19 at 22:29:51



I placed an initial order for some Lii Audio F15 drivers last night.
Hoping to have them in house in the near future .....

A preliminary page has been created on my website.
The information can be viewed here.

Looking forward to Decware Audio Fest 2019 .....

Happy listening,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/25/19 at 00:13:14

Lasb, LOL!  The only thing I hate more than MDF is OSB!   ;D

I'd bet OSB is fairly dead too.  I don't know all that's involved in making sound with OBs but if the baffle is part of the sound then I suspect it would have to be lively like a wood stringed instrument.

Spending WAY too much time with my baffle build.  I sure hope it's worth it.  Mostly sanding, routing edges and building the feet.  I thought I had a simple solution to the footers but I have consistently found nothing is simple with this build.  I plan on painting mine since the BB is too wild.  I know if I ask for color suggestions, Donnie will say red.   :D

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/25/19 at 00:21:26

LR, that guy is my hero.  I didn't have enough time to watch much but he doesn't like MDF and he talked about damping vibration as opposed to "draining" vibration, the latter being constantly thrown around in audio circles.  I still don't know what that means.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/25/19 at 01:00:09

Not just red, Rust-Oleum Safety Red over Zinsser B-I-N shellac based primer.
4 coats of primer, sanded smooth as your first real date's thigh, then about 6 coats of red, again smoooooth, sand with wet or dry paper, from 500 to 2000, some anti swirl compound, and finally a dozen coats of wax.
You will be able to see a reflection of yourself in it.
I may go overboard in finishing sometimes.....


Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 07/25/19 at 02:33:22

Very impressive Donnie...   I have not the energy or patience, but can certainly appreciate the quality end product you achieve.  

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/25/19 at 16:12:46

Donnie, did you write something about paint?  I was completely distracted by " smooth as your first real date's thigh".

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/25/19 at 16:23:54

I used some rattle can spray paint on mine.  A few runs, but nothing to get worked up about.  Not as smooth as anybody's first date's thigh.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/25/19 at 16:39:29

Krylon is your friend!  I'll go with satin black.  Or I could embrace the wildness of butcher block and filler and just clear coat.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/25/19 at 17:03:18

Most of my stuff I have been building lately is painted with duratex.  Expensive but hides all my mistakes.

The low boys were already painted the gloss black so I stuck with that.  I just had to paint where I chopped them off.

I'll never do gloss black again ;)

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/26/19 at 01:21:38

I used up my town's supply of Krylon satin black so I had to switch to Rustoleum Semi-Gloss.  It's not too glossy but boy does it take a long time to dry compared to Krylon.  I should have brush painted them.  Hides better and not so toxic!

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/26/19 at 03:25:10

SUMMARY:  The original plans shown here were a target, the final dimensions I ended up with, that has been documented here, is I think visually better. Also the final result is not a perfect linear scale nor probably should it be.  Also discussed.


Couple comments about the shape and size of these baffles:


Quote:
Here is my plans. I realize these plans will short out a lot of DIY speaker builders who like in-depth plans, but for myself, this is all I ever do... it has all the information I need to build the loudspeaker. The cut out diameter will be determined by the actual diameter of the drivers I decide to use.




This is the starting point. Notice there is no spec for thickness. That's because you don't know how thick your wood will be until you machine it. The thickness will be determined by how much twist there is in the worst board of the bunch.

The board widths of the Wenge and Paduke in the drawing above were determined by eye and were targets. There was no way to know how close to these board widths I would be able to achieve until after all the lumber is machined. As Archie noted, these things are complicated for as simple as they are, especially when you have to puzzle-piece all the wood together to match a particular pattern. Solid Paduke (or any hardwood) would have taken less than 1/2 as long.

I did the arc in the drawing by eye using a 3 point measurement... it is how I've always done it. Usually I will cut a piece of wood or metal that is just stiff enough to strongly resist being bent and then bend it into shape by applying pressure at both ends and let nature and the pressure of my tumb tips define a perfect arc, which I can bias positive or negative just by adjusting the pressure at either end and then looking at the arc. When I see it, I just know it, and then I freeze the shape and mark it on the board.

In this case, since a router would be used with a jig, the arc would be perfect. Still I remember how I set the radius, and it was again done visually as I adjusted the swing to hit the top and bottom at the particular point. That point was determined by the amount of Wenge I wanted to show so it visually matched Randy's baffles he made for me. During this process I recall becoming intrigued that the radius was around 42 inches as is the height of the baffle.  

I had already marked the cutout diameters for the driver so I was also referencing that visually as I set the arc. The final shape of these Big Betsy Baffles was the result of all of the above. Interestingly, when I had to saw two of the wide Wenge boards into strips and glue them back together I lost about 1/2 inch -- that I stressed over because I wanted as much Realestate to work with as possible before I set the final shape and dimensions.

Nevertheless my final shape that I ended up with is slightly more stubby which from an artists eye better serves the 15 inch driver I planned to put in it. So if I measure my pair of Big Betsy Baffles, the actual width came to 33.75 inches. The width at the top and bottom were 22-13/16 and the height came to 42-1/8.  

I think if this actual dimension were scaled back down and the original Betsy Shape was modified to match it would not serve the 8 inch driver as well as the original shape does... if not sonically, visually.  And I think the opposite is true as you go up in size.


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/26/19 at 03:58:47




So now you know a bit more about my design process.  I have found through years of experimentation that perfect linear scaling is seldom a satisfactory way to make something bigger or put another way can always be bested by a more organic approach. If the whole world were linear, yea that would work, but gravity, light, sound, and virtually everything have different scales or 'curves' so when you make one of those items bigger all the other have to use slightly different scales to end up in the same operational sweet spot.

In any case, I tend to agree with Archie, I think we will find that getting the shape identical to mine would be less important and the wood that was used and the process of construction will have a bigger effect.

Having made a few hundred MDF and Particle Board speaker cabinets in the process of Decware, I have a feel for the damping and the sound, and generally always preferred the consistency it brings to the table over hardwoods. However, my impression of these speakers is that the liveliness of the wood brings a small part of the wavefront onto the surface of the entire baffle both front and back so it is like having say a 32 inch driver.  

I will also make the comment that the Alnico drivers I am currently using in the Array, being less efficient and having comparatively little mid-bass slam  would probably sound exactly the same in any material.  The F15 on the other hand is easily 6 or 8 dB louder with the same power and has an insane hit in these baffles. I have never heard them in anything else as of yet... but, I know Dank's ears and tastes well, and have his amplifier, so when he says there isn't any bass in his place it suggests to me that MDF might not work as well. It could of course be where he puts them in the room. Probably there will have to be some adjustment there as the speakers might be more oriented to telling you where they will set in your room and not the other way around. Being the size they are that could be an issue for him and others. The cool think is time will answer this question and the answer will show up here in this thread at some future point.

Dan, one suggestion would be to EQ them a bit while they are breaking in... you know, if you want them to sound juicy give them a bit more juice. I have used the ZROCK2 with these speakers on and off and all it's wonders are magnified by the speaker's efficiency and bass potential which is to say the speakers are tight enough to respond to a juicer signal. During the last demo I spoke of, I used the ZROCK2 with much of the digital, and a ZBIT and a ZTPRE on the front-end.  For the vinyl Demo, I used the ZMC1 feeding the ZP3 phono stage, feeding a ZSTAGE going directly into the amp. The vinyl rig had more slam with the best LP's in my collection.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/26/19 at 05:47:39



Quote:
FF to about 28 minutes in this video.

https://www.youtube.com/watch?v=EEh01PX-q9I

This guy is a great teacher.



It's some good stuff.  The first recording of the stringed instrumental was stunning, it bent my brain.  The second song which I stopped at 34:53 sounded like Spong Bob playing flexible speaker baffles.  In contrast, the same track on the F15 loaded Big Betsy would have simply crushed it.  I have experimented with foam as a baffle for a real speakers and it's a no-go.  As a panel for a Dayton transducer it has some honorable qualities and good efficiency without a lot of or in the case of the ceiling tile, any resonance of it's own.

Nevertheless, the insight is invaluable.  It makes me wonder if the different dynamics of the woods (Wenge and Paduke) are doing a similar thing but in an inverse sort of way.  Each would clearly have a different frequency balance, and both would probably be good, but combined would likely be better.

BTW, congrats on the new house and large shop area! We'll be expecting a pair of something out of you soon!

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/26/19 at 06:38:42


Tonight I'm listening to some new radio station tapes I got, and the sound on this batch of tapes is unreal... I remember it. I know I have heard it as a teenager. It's the exact sound. Almost spooky because you realize it's not the melody or the dynamics or the loudness level, but the timbre. The sound is so transparent, deep and rich, with no compression whatsoever. It's a sound that even if someone stole your woofers, you would still happily listen to because the midrange is so glorious. In todays digital world if someone steels your woofers, the game is over right there, which is btw telling of a missing sort of staying power of analog that is not present in even perfect sounding digital. Perfect sounding digital when hacked sound hacked.  You take the bass or the treble down and the sound falls apart. These analog tapes you could dissect into pieces and the sound is holographic, it just somehow makes itself whole again! Simply amazing. Hearing the actual exact sound/timbre after some 40 years was an unexpected time machine that literally appeared unexpectedly and blew me back to the summer of the mid 1970's.  

This is making me wonder what's going on...  it sounds too good.  Like I've never heard it like this since I was a kid.  It it the Array?  What would happen if I had the F15's in there right now?  Would I be feeling the same way, or would it move to a holy-crap level?  Gee, now I understand the original vision I had of these baffles that had a removable clamping system so that any driver could be installed in minutes without risk of damage.  You know any time you change a woofer using a screw gun in front of more than 10 people it is a certainty you will slip and put the bit through the speaker surround.  

I of course could put inserts into the baffles and run the original betsy drivers or the alnico drives and would probably shit my pants at the things it brings out in the sound but then I though about a slot that perfectly accepts the original Betsy Baffle so that you could actually just slide a Betsy into the big baffle.  Another woofer less sub-woofer, the best kind ever.

Since reading somewhere in this thread that the Lii 10" Crystal driver is bass shy and prefers a box, getting the sound of the 8 inch Betsy Alnico driver with the bass scale of a Big Betsy may not actually require anything other than a larger piece of wood.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/26/19 at 14:57:07




Quote:
Since reading somewhere in this thread that the Lii 10" Crystal driver is bass shy and prefers a box, getting the sound of the 8 inch Betsy Alnico driver with the bass scale of a Big Betsy may not actually require anything other than a larger piece of wood.


Hi Steve,

This is true ..... based on the baffles I have built over the past couple of years, the larger the surface area of an open baffle, the more bass it produces.  One of my audio buddies (Derek) built a pair of 4' x 4' baffles using the original Betsy drivers and called them the "Donkey Kongs".
They made enough bass in his listening room to make my knee caps buzz .....

It's a balancing act though ..... too much bass response can overwhelm the mids, or at least obscure them. I also believe that the size and characteristics of the listening room are part of the equation.
In a larger room, the Donkey Kongs would probably have been more "balanced".

Of course, the shape and materials used in your BIG BAFFLES would have a big effect on the overall sound ..... so the 8" drivers in those baffles might be totally killer .....

Best wishes,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/26/19 at 15:12:35

In my current OBs, the Tang Band 1808 has a relatively big flange around it so the opening is pretty big.   I made an big "O" insert that allows me to test a few smaller or equal size drivers in my baffles.  

Not a quick change setup by any means, but it allows the ability to test other drivers.  In the past, I have put in a different driver and listened for a few days or  a week and then switched back to compare.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/26/19 at 15:53:34

My drivers are scheduled to show up Monday.  I'm nervous in my anticipation to hear if only Steve is blessed by the Audio Gods.  I'd hate to think a week's worth of work could be in vain.

After reading Steve's build details I see that I basically have a baffle that is 1 inch narrower than his.  If that inch, maple instead of his exotic blend of HW and my painted surface makes a difference then Steve ought to be buying lottery tickets since his intuition/luck is beyond belief!   ;)


Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/26/19 at 15:57:36

Good luck Arch.

Mine are arriving today but I am in Michigan, not Illinois.  Hopefully, UPS will deliver to my neighbor as requested.

We'll see how the MDF sounds in the low boys.  I have another system set up to run them in.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/26/19 at 16:05:15

Watching more of LR's video link, MDF is not more "dead" than plywood.  So, what could be going on with Dank's MDF baffles and the lack of bass?  Maybe it has to do with the lower stiffness of MDF which would lower its resonant frequency which could interfere with bass production?

All just a guess.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/26/19 at 16:24:26

Now Tuesday.  UPS is claiming "severe weather delay" between So. CA and CO.  Sounds like they are taking a page from the Airlines when it comes to excuses.   >:(

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/26/19 at 16:34:33

Disappointing  >:(

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/26/19 at 17:17:36

I might need to fire up my saw this weekend. You guys have given me the "itch" to build something.
I have material, drivers and tools. Oh and some red paint too.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/26/19 at 19:23:56

Keep it smooth Donnie. Keep it smooth.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/26/19 at 21:21:52

Now it's back to Monday.  I guess the extreme weather cleared up.   ::)

Paint is interesting to work with.  Has anyone tried buffing with say 0000 steel wool and then coating with wax?  Or maybe just some rubbing/polishing compound?  The surface laid down out of the can can be a little rough.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/26/19 at 22:08:10

Here is another video by the speaker builder LR originally posted.  https://www.youtube.com/watch?v=CKIye4RZ-5k

He's making flat panel speakers and I think that some of what he's analysing is applicable to OB speakers.  At 8:25 he talks a bit about shape and at 12:50 he talks about where to put the actuator.  Interestingly, he uses a 3/5 2/5 rule.  Randy and Steve seem to be using this vertically.  Steve's driver center of 25 1/4" in a 42.125" baffle is 3/5 up.

His whole point with the shape and driver offset is to break up panel resonances.

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/27/19 at 05:16:06




Quote:
His whole point with the shape and driver offset is to break up panel resonances.


Hi Archie,

That makes perfect sense to me .....
It's kind of interesting that the first few Betsy baffles I built had the driver centered vertically. The more I looked at them, the more it seemed to me that raising the driver slightly above center was more aesthetically pleasing ..... so I started doing that.

One day, I was visiting one of my customers who owns one of the original pairs (with centered drivers). I had a new pair with me and we did an A / B.
Amazingly, we both heard a difference.  The one with the centered driver was a bit "warmer" sounding and the one with the raised driver had a bit more high frequency emphasis.
We chalked it up to the drivers in his speakers being closer to the floor .... but that's just a guess .....

Best wishes,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/27/19 at 17:28:56

I like the physics as a point of interest but generally I just follow guys who've figured stuff out already, like you and Steve.  The idea of an aesthetics or beauty to what works is more often true.  But beauty is in the eye of the beholder, as they say, which lends me to believe that it can take intuition to see the beauty.  (Steve's Audio Gods)

When I worked in the Aerospace industry there were guys who would "conceptually" design like an artist and the real thing ended up looking like the conceptual design even after all the in-depth analysis was done. :)


Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/27/19 at 18:13:44

Organic design is a real big thing in high end engineering.
To build something strong, look at how a tree holds itself up.
To make something flow, watch how a river works.
I suppose to understand how things sound maybe we look at ears?
Dunno, I just make equipment that rapes mother earth, I'm good with that, the paychecks don't bounce.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/28/19 at 04:03:38

UPDATE 7-27-19

Despite the magic soundstage and overall frequency balance that I get from the Array, I will be putting the F15 drivers back in and running them solo prior to DECFEST 2019.

Why? It should be understood that in the Big Betsy Array -- by design you can not hear the large baffles unless you put your ear up to the speakers. They were designed to support the Betsy Alnico with the utmost subtle amount of sound so they would not detract from the Betsy Alnico speakers in any way and they do it exquisitely well. However by comparison to what the large baffles do with the F15 drivers, I feel like it's almost a horrible waste of such a great large baffle despite how incredible it does sound in the subtle roll it plays in the Big Betsy Array configuration.  It is so right, that it is a new personal reference as of right now.

I have run the F15's in the Big Betsy cabinets with a 12dB passive 90Hz crossover and paired that with the Betsy Alnico to create a similar array and while not as seamless or organic, it did actually work rather well. Problem with that was that using the F15 as a subwoofer felt like a horrible waste of such a great full-range speaker.

Clearly the best bang for the buck is the Big Betsy fitted with the F15, because what those two things do when paired together is more than memorable.

So this puts me back in my original dilemma, in that the speed and sound in general of the Betsy Alnico speakers takes the midrange and top end to another more realistic level in my room. I want that sound, just with more scale and ideally from a single pair of baffles... but with some of the Big Betsy Slam which exceeds any speaker I've ever heard that was actually listenable.

So I have been pondering the Lii-Audio Crystal 10 drivers at $1000 for the pair based on the performance and build quality of the F15 I don't think I'll feel like the drivers were over-priced once I get a pair, so I have ordered them tonight.

Meanwhile I've been working on a new baffle design for these specific drivers. With a lower QTS they obviously want a box and not an open-baffle. The Crystal 10 has a QTS of about 50 whereas the F15 has a QTS around 70 or more. A higher QTS woofer is desirable for open baffle, because the magnet strength is lower to allow the driver to move more at its resonant frequency (fs). This creates a bass boost at resonance that helps offset the cancellation of low bass that the baffle creates by letting the rear wave from the driver come around and cancel the front wave from the driver. This happens at and below a frequency determined by the size of the baffle.

To get a lower QTS driver to work, a larger baffle would be needed and or some bass boost equalization. Let's talk about the baffle size first.

When I scaled the Betsy up for a 10 inch driver, I just felt the size wasn't big enough to give any of that Big Betsy thrill, especially with a lower Q driver that has somewhat elevated highs.



So on the left is the baffle scaled for the 10 inch driver. Next to it is the Big Betsy. The next two are sizes I was trying to pic from and the last one is the original Betsy size. This gives the eye a sense of the scale.  I choose the one that is colored light blue in the picture.  It's going to be about 34-3/4 inches high and about 28 something wide.

The Audio Gods are guiding this one, as I am investing a lot of time and money into it without knowing for sure what will happen. I'm usually rewarded for such faith so we'll see what happens.

Now lets talk about bass boost equalization. You might think at first "no way" not a purist move, etc, but consider this...  the lower Q driver has a stronger magnet hence more bass control, i.e. tighter, faster. There is more control at resonance, which btw, in the case of the Crystal 10, will be in the mid 30's, not 49Hz like the F15. So adding some bass equalization will restore the missing bass from the low Q driver while the drivers stronger magnet will keep that bass even tighter and better controlled. That makes the whole key the EQ. This is were most would botch the concept, but a single-ended class A triode running all by itself with zero negative feedback could easily achieve this with total transparency. Ironically the perfect curve and adjustability for this can be found in a product we already make called the ZROCK2.

So once the speaker is completed I will be pairing it with a ZROCK2. My hope is that this will get me somewhat close to the stock Big Betsy F15 speakers, but with sound that I would fully expect to best the Betsy Alnico drivers on every level.  If this is successful, it will be my personal holy grail of open-baffle loudspeakers.  

If I don't run into problems, these will be done prior to DECFEST and can be compared to the Big Betsy with the F15.

Title: Re: Steve's BIG BETSY Project
Post by ScottNC on 07/28/19 at 04:38:16

I can’t wait to see/hear how this pans out...never a dull moment that’s for certain [smiley=10.gif]
It just keeps getting more interesting
Scott

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/28/19 at 05:10:28


I will of course document the build with pictures as before.

I spent the day today making some of the boards from a stash of really old walnut that was my dads. I'm shooting for a thickness of 1.5 inches. The walnut boards are 6 or so inches wide by 36 length to start. They will be glued up into a total of four 11 inch panels to start things off.  The center stripe will be 5 inches... the radius of the driver.

It was a lot of jointer action since these boards were all over 2 inches thick with a lot of twist to them. In some cases a 1/2 inch in 3 feet.  Between the jointer and the planer, I filled up my dust collector bag past the top and half way into the top bag before I realized it! Trying to get the bag off the dust collector when it's that full is not an easy task. Nevertheless I freed the bottom bag and then about 10 gallons of dust dumped on me from the top bag and like Mt. Saint Hellions it emitted a dust plume that had documentable devastation to not only me but a large part of the shop. Had I known I would write about it, I would have taken a picture of what I looked like. I know that orange haired Bob can relate to this ; )

Anyway, after getting all that cleaned up, the day finished with all the walnut boards I think I will need to make the two baffles. The center strip will be either maple or AAAA+ figured oak.  Something lighter for contrast but with striking grain since it and the driver will be the focal point.

I have some insane figured oak already in stock but it's 4/4 not 8/4 so I would have to glue it together, which I probably will, because I have it.  I want to create something equally stunning to look at as the Big Betsy baffles, in this more manageable but still substantial size and weight.

On a side note, I spent some more time examining the roller guides on my new band saw that are nearly an 1/8 away from the blade which BTW is why the saw dropped an F-Bomb when I tried to cut the Wenge. I discovered they rollers are camed (sp) and figured out how to adjust them to a few 1000's from the blade so now it cuts Wenge just fine, and cuts walnut literally like it was styrofoam! So with this new confidence I ripped all the 8/4 to width on the Bandsaw instead of the table saw.  No noise, no dust, to wasted wood, same precision and same speed. Amazing! Yes, I admit it, I'm getting off pretty frikin hard on my long overdue wood shop. My whole life as a contractor and hobbyist and then union carpenter and eventually speaker designer was tormented by twisted and or crowned boards that you had to wrestle into submission and sand the shit out of to make anything halfway presentable... so you can image what a thrill it is to be able to take tormented wood and make it perfectly flat, perfectly square and perfectly straight... really I can't emphasize how erotic a sensation this is, instead of suffering I'm tripping!


Steve

 






Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/28/19 at 05:40:16


Until I get some photos of this new build, here is my sketch (target).  (For engineers, this is my personal 'shorthand'.)





This one is also Randy Inspired, as seen on his web site Caintuck Audio Loudspeakers.



The difference will be that the darker wood will be walnut, the lighter wood probably highly-figured oak.  

The picture above is the inspiration for this new speakers appearance... Randy strikes a great balance on this one with the board widths and wood choices.  So now (if you've been following this thread) we know that Randy is not only an alien but a pretty good artis as well!  

I might also mention that the pictures of Randy's listening room as of late, are pretty telling of a past life as a Zen Buddhist monk from Japan.  ; )


- Steve

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/28/19 at 13:50:45

OK, I'll wait before I rush in and make new drawings. Lol
Good tools, aligned and sharp are a pleasure to work with. It is so nice to be able to produce what your minds eye can conceive.
Steve, do you have room for a CNC router? New levels of precision and speed are available.
Also I noticed on the Lii Audio website that if you buy a pair of Crystal 10's you get a pair of F15's for free! A twofer.
What could someone come up with for both pairs to be used in one speaker?? Hmm....
Edit:
Steve you really should look into additive manufacturing (3D Printing) talk about freeing your mind from conventional thought. If you can dream of a shape you can make it.

Title: Re: Steve's BIG BETSY Project
Post by hdrider on 07/28/19 at 15:37:55

This thread is what I LOVE and what drew me into Decware. A creative idea that gets grabbed ahold of by others and experimented with and everyone shares their thoughts experiences. While I don't have room or the talent to work wood at your levels, I do have a master woodworker/friend two houses down that I could enlist....Keep up the dialog lads, you have made for a wonderful Sunday morning listening to our Decware rig and reading this thread. Happy listening, Chris.

Title: Re: Steve's BIG BETSY Project
Post by BAndrade on 07/28/19 at 17:24:17

Steve (and all other contributors to this thread), thanks for sharing your development process on this project. This is the type of nitty gritty that I drool on. It also takes courage and confidence to lay a project bare from the beginning not knowing the outcome, but everyone learns so much from. Both from the little successes as well as the little mistakes along the way.  

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/28/19 at 18:38:59

Steve, you've never mentioned what jointer you have to tame those wild boards but since you obviously get off on tools, check out the Northfield jointers:  http://www.northfieldwoodworking.com/jointers/jointers.htm

I acquired a 12 inch HD model that had been used in Hughes Aircraft's pattern shop in the 1960s.  They are real battleships weighing in at around 1700 lbs!  They even have a ship's wheel to adjust table height.   8-)

I used mine to polish the endgrain on my big betsy baffles.  What a joy!

When it comes to jointers, size matters.   ;D

Oh, Donnie, that promotion is over.  I checked.

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 07/28/19 at 20:06:51




Quote:
So now (if you've been following this thread) we know that Randy is not only an alien but a pretty good artist as well!  




.....


Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/29/19 at 01:30:35

I may have finally figure out how to post a photo.  If so, here are a couple crappy pictures of my baffles.


Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/29/19 at 01:31:51

And the other side.

Title: Re: Steve's BIG BETSY Project
Post by Geno on 07/29/19 at 02:27:05

Nice, Archie!  Looks like, in a matter of days, you’ll have music playing. Looking forward to your report.

I’m really enjoying this thread. If I had the wood working skills, I’d be more of an active participant.

Good luck to all you craftsmen!

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/29/19 at 04:09:33

So I'm going to call this one the BESTY10 for now.


It starts with the wood, and this stuff is old. I started with 8 pieces of 1.5 x 6.5 x 36 inch boards, which I made. This morning I realized two of them would have to be rejected. One was too good and one was too bad, so time to make two more. Sadly that's all the wood I'll get from this plank by the time it is machined.



On the table you can see the one that didn't make it. You can see the fault line... even though it wasn't actually cracked, it has a high probability so it's just not worth it.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/29/19 at 04:19:29



The goal is to create four 11 inch wide x 36 x 1.5 inch panels and some 5 inch x 1.5 inch boards for the center strip out of highly figured oak. Here is the first walnut panel getting glued up. On expensive stuff like this I do one glue joint at a time. I takes as long as it takes. The way I figure it a solid hardwood loudspeaker is going to last forever and will never be thrown away so the time it takes to make a pair is somewhat irrelevant. It has taken me two days at a leisurely pace just to create the 11 inch panels and the 5 inch center boards which will all be glued together to create the baffle.




Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/29/19 at 05:16:14


 

For those who aren't into woodworking, trying to figure out which way to flip the boards and how to deal with knots and misc issues makes it challenging and time consuming. If the wood was perfect it would be a simple experience, but when you have to make the wood perfect from imperfect wood and still have enough to do the project, it is a real puzzle.  This is why it takes so long, and costs so much, but the end result is just that much more appreciated since we know it didn't come easy.

I will say that as I put these panels together I can get a good sense of the size which now feels a lot smaller to me than I though they would be judging from the sketch where I choose the size. I probably should have chosen the size above this one for better performance. The thing is there are about a million people who will not ever buy a pair of Big Betsy speakers because they will think they are too big. This will be a far more manageable size that fall somewhere between an original Caintuck Audio Betsy Baffle and the Big Betsy Baffle shown earlier in this thread.

The difference between 1.5 inch and 1.75 inch, the difference between 35 inches and 42 inches, and the difference between Wenge/Paduke and Walnut/Oak are huge. Compared to the last project this seems like half as big. I won't have any problems lifting this baffle, even when fully assembled. The Big Betsy is a BEAST by comparison.

I could probably cut the arc on my bandsaw, which btw, is kicking ass now that I figured out how to adjust the guide rollers. I used it for all rips today and yesterday. I haven't turned on the table saw one time so far during this project. It's so amazing that the speed of the cut is the same as the table saw, but there is no noise, no dust, and no waste. It rocks!

Archie, Great baffles! Also I looked at the link for the jointers, holy crap! A 24 inch jointer! Just imagine that! I suppose when surfacing a 24 inch wide panel on one, you would have someone sit on the panel as you push it through ; ).

My jointer is a Grizzly 8 inch wide with a serpentine belt, and spiral cutter head. It is my favorite tool in the shop. I love it's precision. I love the feeling when I have just made a pass with a 6 or 8 inch board and go to pull it off the cast iron out-feed table there is a suction from it being so flat! I love that there is no snipe unlike a planer. I love that I can run any hardwood through it backwards against the grain with no tear out. I love that I can put the most highly figured dense hard wood through it and not only is there no tear out, or chipping, there are no marks and it has the finish of something that has been hand scraped.  Sanding it would only make it rough. It actually shines. That really gets me off hard, you just have no idea how much!

Happy listening!

Steve



Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/29/19 at 14:22:55

I returned home on Sunday afternoon to find my drivers had arrived.  After a quick install here are my initial thoughts.  

I would label this review as the “challenged installation and setup review.”

First of all, my goal was to just get the drivers in the 1.5” thick MDF square lowboy baffles so I could run them in a little before any critical listening.  I wasn’t concerned about placement, etc.

I started out with the drivers not fitting the baffles. I thought I had plenty of room a 15 1/8” to the outside hole for flush mounting.  Easily 1/8” or more off.  So I got some long deck screws and more or less surface mounted the drivers.  Problem was that one side always wanted to sink into the existing cutout.  Suffice it to say they are a little crooked.  

Because I was just running them in, I placed them on top of my subwoofers.  I didn’t want to put them in front of or move my existing speakers and I have limited floor space.  In this position the whizzer cone was about at ear level.  They are maybe 6’ apart.

So how’d they sound given these challenges?  After a few hours, very very entertaining.  

First of all they completely disappear. Second, they produce a huge soundstage.  The bigger a piece you throw at them the better.  Think large scale classical.

Third they are well balanced top to bottom. I did not come away thinking they were too rolled off or bass shy.  Perhaps on some really heavy bass tracks I wanted to turn on the subs but the bass is quality so you forget about wanting more.  You just kind of tune into it.

Imaging was great as well, even with all on one minute of setup time.

They definitely have “pop”.  So much so that on a few well known songs I was startled by a snare hit or trumpet blast.  I wouldn’t confuse this with beaming. It’s just the efficiency of these allows a lot more of the recording to come through.

Last but not least and probably their biggest strength is the timbre of the instruments and voices.  One example is the snare hit.  I haven’t had a pair of speakers get this right.   Bass is textured.  Acoustic guitar sounds “Woody”.  Certain voices sound “reedy”.  I’ll have to try piano next.

There was a bit of harshness to them for the first couple hours but I had all this other new sound to tune into that it didn’t bother me that much.

Suffice it to say that these drivers, while poorly installed and setup, entertained me for the next 3 1/2 hours and I got up early and listened for an hour.

I listened to all kinds of music. Rock was the only genre I was a little light on.  I had the volume considerably lower than usual but lower volume passages on all tracks kept coming through.

Given they are new drivers I didn’t go too high but I turned it up a few times and they didn’t distort.

So even at this early stage these are a thumbs up for me.  They may replace my current OBs.  I’ll go ahead with a hardwood baffle build.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/29/19 at 15:37:27

Steve, a spiral cutter would be nice!  I always do my best to orient the wood grain slant correctly through the jointer and planer but often it goes both ways!  Maple seems the worst.  You have more patience than I when it comes to glue-ups.  I typically do it all at once.   And of course, for anyone wondering, IMO a good jointer is the key to any woodshop.  Although I knew a cabinet maker that didn't use one.  He had a sliding table on his table saw and some amazing blades.

FWIW, I used my bandsaw to cut my arcs and while I'd likely do it that way again, when belt sanding the edges smooth, there is a slight tendency to develop a bit of a bevel in the edge.  For a perfectly square edge, the router is probably still the best way to go.


Pal, how is the top end so far?  I'm wondering if these will benefit from a super tweeter.  What kind of break-in are you thinking?  I know I'll have a hard time resisting the urge to CRANK!

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/29/19 at 15:43:55

Arch,

I didn't feel the need to try the Super Tweeter yet.  I will probably experiment with it at some point.

I did turn on the subs and they integrated really well, however, I had to crank up the crowns feeding them to put out enough volume.

I kept thinking I would like to hear these with the built in sub cabinets Steve has in his listening room.  Those speakers put out bass that would be on scale with these drivers.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/29/19 at 15:46:58

It's interesting that with the 15" driver you tried a sub but not a tweeter.  I would have thought just the opposite.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/29/19 at 15:54:35

I am trying to resist the urge to complicate this setup.  

I contacted Leo at Lii and he said they will get better with time, especially the bass.

I have just been listening to a system with subs for the last 6-9 months and while the bass is adequate, I did miss my sub 30hz bass on some songs.



Here is my breakin setup.  It doesn't really show how close the drivers are to each other.  I can imagine how good the soundstage will be once I move my existing speakers and start to position them correctly.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/29/19 at 17:20:11

Wow!

Actually, the low base was why I was looking at the Crystal-10s.

Do you have a ZR2?

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/29/19 at 17:24:27

Only a Zbit

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/29/19 at 17:30:03

I'll be interested in hearing what my ZR2 does with the F15s.  I don't have huge subs now but with the ZR2 my HR1s put out some very low bass.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/29/19 at 17:47:19

Yeah, I have read of the merits of the ZR2.  I'd be interested to hear what it sounds like with these drivers.  One of those units may be my post Zenfest purchase this year.

Its a bit of a long story how I ended up with 2 15" subs in my little room.  They will hit 25Hz and the bass is fairly tight.  I cross them at 50Hz.  The integration is pretty seamless.

However, I am running them with a fair amount of power from dual crown amps.

As I said before, the Palomino Audio Project ballooned into a multi-driver, multi-crossover setup.  While they sound good to me, I am looking for something simpler.

Title: Re: Steve's BIG BETSY Project
Post by Lon on 07/29/19 at 17:57:29


Archie wrote on 07/29/19 at 17:30:03:
I don't have huge subs now but with the ZR2 my HR1s put out some very low bass.


Mine does too. I have one in both of the systems I use most, and both those systems now also have a ZBIT. The one with the 25th Anniversary mods took the longest to break in of any of the Decware components I have but boy does it sound fantastic.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/29/19 at 22:57:42

I have my version of the Big Betsy playing and as Steve might say, HOLY SHIT!  Now I know what he means my big sound and "it is here" versus "you are there."

These play loud and so far very clean.  I will say categorically, you can't hear what they can do without a ZR2.  They sound anemic, by comparison, on Bypass.  The ZR2 is arguably Steve's greatest gift to the audio world.  I'm not sure my HR1s will be getting much play time going forward.  It's not that the HR1 is any anyway a bad speaker, rather, I have a huge room with tremendous volume and the HR1s just can't quite fill it.  These do at 10 o'clock what the HR1s did at 2 o'clock which is close to clipping.  And the headroom!

The OB design is new to me and it's funny how the sound comes off of the back.  I'll post a series of pictures just to show off but also to see if I can get suggestions on best toe-in (if any) and distance from the wall.  My rear feet give a 12" distance, minimum, and I can get up to maybe 3' by pulling them out from the wall.  I don't seem to need toe-in to image but I am thinking it might help the rear wave from just banging straight back into the drivers.  Unfortunately, sound treatment just won't work in my room.  I have a nice full soundstage between the speakers but not holographic or outside of the baffles.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/29/19 at 22:58:53

Sorry, I don't know how to make the pictures post smaller.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/29/19 at 23:00:33

The back:

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/29/19 at 23:01:58

The footers:

Black paint shows everything and the paint job isn't the best but my total cost was under $500 since I had everything on hand but the drivers, paint, footer pads and driver screws.

Talk about bang for the buck!  Or maybe dB?

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/29/19 at 23:12:38

Arch, good to hear you like them.  I forgot about Steve’s comment about they are here but do agree with it.  

My OBs are about 4’ from the back wall if memory serves.

The ZR2 comment has me intrigued.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/29/19 at 23:17:02

I do agree with it.  The sound is so big that for the first time, they have the potential to put the piano in my living room.  And I have one there so I know the difference.

I've found that Steve's "hype" generally exceeds my experience (I'm sure it's my fault) but with the ZR2 he doesn't talk it up enough.  I think he should incorporate the circuit in every amp he sells.

I can't do four feet from the wall but I can see where more distance might benefit.  Do you toe your OBs?

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 07/29/19 at 23:18:08

Archie,
Very very nice.
I'd pull them out 3' and listen, I bet that they will sound even bigger and more glorious.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/29/19 at 23:28:45

Yes.  I can’t tell you the exact angle but they are pointing at my head.  I started out with them flat but increased it bit by bit until I got what I think is an optimal mix of soundstage depth and width.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/29/19 at 23:34:16

The nice thing is that although these weigh 63 lbs each, I put them on thick felt pads and they slide easily on my wood floors.

I bet Steve's weigh more like 80 lbs+!

Thanks Pal, I have mine toed some and I'll play with that more.  I actually rarely listen while sitting in front of them but it's nice to occasionally stop and stand and take in the sound.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/30/19 at 00:49:48

It's going to be hard to get anything done.  My whole LP collection will have to be gone through now.

I know it's early but as far as bass is concerned, I think my HR1s may dig deeper.  I still need to play some of my deep bass pieces.  The F15 bass is very tight though while the HR1 can sound a bit flabby at its deepest.  This is with the ZR2 for both.  Without the ZR2 I would rate these bass shy.

I haven't said anything about the mids or highs since they sound completely great.  Hell, it ALL sounds great!   :D

Steve, have you done any measuring/comparing, instrumentally or subjectively?

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/30/19 at 01:11:09

A build note that might be helpful is that I cut my driver holes just over 14"D and less than 14 1/16".  The drivers fit with a tiny amount of play.  The screw holes were about 1/4"+ from the edge.  I recommend keeping the opening a small as possible to give the screws some margin.  I used #10 pan head screws at 1" long.  My baffles are 1 1/2" thick and I used a 1/2"R round-over bit for the back of the hole.

As I type this I'm playing some heavy bass that is there, and tight!

Title: Re: Steve's BIG BETSY Project
Post by Geno on 07/30/19 at 02:28:43

Awesome Archie! Welcome to the open baffle gang. There is nothing like it.
Don’t be too quick to judge. I’ll bet that after about 50 hours of break in, you’ll really start to hear a difference. Like Pal and Donnie said, get them out from the wall behind at least 24”.  My Lil’ Betsy’s are toed in just shy of pointing straight at my head.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/30/19 at 02:55:00

I’d give the bass some time to develop. Tonight I am getting a lot more than yesterday.  Keep running them in.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/30/19 at 03:19:49




Got them glued up today. Cutting the top and bottom to size so I can do the dreaded arcs. While I could put this through the band saw and spend and hour with a sander, I know I wouldn't get it straight and since it wouldn't actually save any time, it would just be a lot less traumatic with the risk of blowing out the side and the mess gone.

Steve




Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/30/19 at 03:25:40




When I get in the mood to cut the second one, I'm going to sticky it to a piece of plywood instead of foam board. I took 3/16" passes to keep from blowing out the side. It takes a long time, but not as long as trying to fix missing wood.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 07/30/19 at 04:26:12




Here's baffle number one...  Will cut number two when I get more time.

These things are tiny... they are not Big Bestys that's for sure.  Even with a ZROCK2 I do not expect these baffles combined with the Crystal 10 to have anywhere near the bass performance and extension, which is frankly kind of sad... but I have to keep my eye on the ball here... Anything larger than this baffle is going to look stupid because the 10 inch driver will get lost, and since the driver is a much lower Q, a baffle even larger than the Big Betsy would actually be the only hope of getting a similar percieved bass output.

As I build these and sort of remote view what they are going to sound like, I predict the Original Betsy Baffle with the 8 inch Alnico driver will sound like it has more bass. With a ZROCK2 the scale may be able to be tipped to slightly outperform it, which would be expected in a bigger package like this. The big thing it will bring to the table is that the efficiency will be the same as the Big Betsy with the F15! This is game changing when you have a low powered triode amp.

Bottom line is simple; as long as it sounds warm and full I don't really care where the bass rolls off. I'm sure it will be pretty high in this baffle that somehow in real life has shrunk drastically compared to the stupid drawing I made of all the different size choices. I now know that the size I wanted would actually be 4 inches shorter than the current Big Betsy Baffle, so 38 instead of 42 inches.

This is the part where following the Audio Gods gets a little squirmy.. like when you don't think it's going to work. I got a smaller baffle than I thought I wanted, and if I built the slightly bigger one that is 38 inches high, that too would be a disappointment sonically when compared to Big Betsy with the F15. So I predict that this baffle paired with the Crystal 10 will be an attempt to do what the Alnico Betsy Baffle from Caintuck audio does but with 6db or more efficiency. I also predict that if these drivers are as good as I hope I will install them into the Big Betsy Baffles with a black adapter ring at which point I will probably be damn happy I didn't built the 38" high models.

I have received some recommended box plans for the driver which I am sure would sound great, but they aren't going to be open baffles and since the midrange on these drivers is suppose to be the holy grail, I don't wan't alter it in any way with a box... at least not at first. Paired with a 2 watt amp I need not worry about over driving them at low frequencies, so a ZROCK2 should very well.  

Another application would be to pair these 34.75 inch baffles up with my Imperial SO horns which I occasionally use with the ZOB/FRX2 combo.

I suppose looking into the future the final analysis will be between the Big Betsy with the F15 and the Big Betsy withe Crystal 10 / ZROCK2 combo.  Both drivers have similar moving mass but the Crystal has a lower fs meaning a looser suspension for a more natural sound.  This suggests that while it may sound better than the F15/Big Betsy combo, it is never going to have the same slam because the suspension won't be as tight...

Kind of like the game of chess isn't it.

Steve






Title: Re: Steve's BIG BETSY Project
Post by Brian on 07/30/19 at 04:48:50

Steve,
The Walnut together with the figured Oak is looking very nice.

Brian

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/30/19 at 14:02:30

Well, the bass has really come in on these drivers.  Before it was polite and detailed, now add full and deep.  Part of that has to do with moving the baffles and positioning them properly on the floor.  But it probably has more to do with the drivers just getting some hours on them.

The low boys are too low.  The image is above them, but lower than I like.  The final baffles will need to have the driver positioned higher.  I’ll follow the Randy recipe as closely as I can.  I may need to scale it down a little.  I was looking at 42” high and I think that will just be too overwhelming for my small room.

Unfortunately, its going to be several weeks before I can start to build.  I may try to build some quick and dirty risers to place them on until I get time.

You know, if I had to do it all over again and were just getting into audiophile sound, I would buy a Zen UFO and a set of these drivers in Randy’s baffles.   That is the price to performance ratio that beats anything I have heard (or built).

If I had a little more money, I’d get a Zbit or Zrock, some Zen Styx, Silver ICs and call it a day.  If I had a couple grand more, I’d get a 25th.

Also, a health warning.  Like its easy to drive a well-made car too fast and not realize it, you can drive these speakers too loud.  Last night, I was inching up the volume and I took out my phone and measured on an ap and I was at 94db.

Title: Re: Steve's BIG BETSY Project
Post by Geno on 07/30/19 at 15:09:33

Good point on the volume, Pal.  I have a touch of tinnitus, and use my app to check that a good bit. I seldom get much over 85dB anymore. I'll bet it is very easy to get too loud with those big boys.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/30/19 at 16:54:12

They can get loud for sure.  I find they have less of a "bloom" than my HR1s and sound satisfying at a wider range of loudness but cranking them and being totally immersed is quite seductive.

I listened to some King Crimson last night and either the re-pressing isn't very well mixed or these just over accentuated the bass.  It got me thinking about isolation under them.  I'll give it a try.  My big wood floors like to get in the game when they shouldn't!

I also wondered what would happen if the driver was also offset 3/5 to one side of the baffle to further break up unwanted resonance.  This might be simulated by bracing the back of the baffle to one side.  I have a test record with a 20Hz to 20KHz frequency sweep on it.  If I put my ear on the baffle during the sweep I can hear 2 or 3 distinct resonances.  I have no idea if/how these affect the sound.

We need someone to build a pair of these baffles out of 3/4" plywood.  If they still work then that might help alleviate the shipping/weight issue around producing the Big Betsy for general sales.  Although, they are still huge.

Title: Re: Steve's BIG BETSY Project
Post by lazb on 07/30/19 at 19:25:14

What happens if the DNA box is scaled up for the 10" driver?

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/30/19 at 19:39:28

I think somebody goes the the hospital after trying to move it :)

Title: Re: Steve's BIG BETSY Project
Post by lazb on 07/30/19 at 20:47:49

Oh, I don't think so. The DNA2 is not that heavy so why should a 10" version be so bad? 10" is 25% more than 8" but that is only diameter. The DNA2 is not twice as large and heavy as the DNA. It was only a thought. The DNA2 has sufficient bass for all practical purposes. Uh, except, I forget, we are mostly not always practical!! ;-)

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/30/19 at 20:51:30

I guess I remember it wrong.  I thought they were double walled beasts that felt heavy at the last fest.  But hey, if somebody could pull it off, I'd sure like to listen to them.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/30/19 at 22:33:21

I'm not sure how the scaling of the DNA goes but for the baffles the weight has to be way more than double.

I spent part of the day building isolation platforms for my Big Betsys.  I had do do a "template" base first to fine tune the position of the springs so the things would sit without a tilt.  I'm going to say that isolation was a big success.  Bass is tighter and much less distorted at high volume.  And when I say high volume I literally mean Rock Concert level.  It can feel like a frontal assault!   :)

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/30/19 at 22:35:37

And a close up showing some of the springs.  The springs act as a vibration filter and mostly only allow frequencies through near the fundamental frequency of the platform with the speaker on it.  In this case it's a couple of Herz.

Title: Re: Steve's BIG BETSY Project
Post by Geno on 07/30/19 at 22:39:21

Adam, What exactly are you using between the two boards, and exactly how far from each corner are they?

Title: Re: Steve's BIG BETSY Project
Post by Geno on 07/30/19 at 22:41:35

Ooops! Jumped the gun.  I see your latest photo now.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/30/19 at 22:55:16

Geno, I put the springs close to the edges for more stability.  For my amps and TT I started adding foam between the equipment and top of the platform to try and mop up the higher frequencies that are transmitted through the spring itself.  Someday I'd love to be able to put accelerometers on one of these to see just what it does.  Subjectively, they cut a lot of vibration.  In the case of the speakers I'm trying to keep them from putting energy into my floors.  If I had carpet it might not be an issue.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/30/19 at 22:55:27

Hey Arch,

How are your supports attached to the baffle?  Glued?

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/30/19 at 23:42:39

The footers are 3"X3" but are made up of 1-1/2"X3" pieces.  I notched the bottom of the baffles and screwed the 1-1/2"X3" pieces to the baffle with 2 huge GRK fasteners.  I then glued the front and rear top 1-1/2"X3" pieces.  I dado'd the rear top and bottoms to accept the 1-1/2"X3" cross piece which is screwed in from the bottom.  It's all very solid and stiff.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/31/19 at 00:21:43

Looks great.  Thanks

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/31/19 at 00:34:07

I took a different approach to Steve's.  I liked the idea of a continuous footer while still keeping the baffle low to the ground.

Title: Re: Steve's BIG BETSY Project
Post by Brian on 07/31/19 at 03:47:39

Archie,
It sounds like you are getting some great sound!

A way to resize pictures is to do it before posting. You can do this in an image editor. I use the one called IrfanView, but there are others.  I got mine from Tucows http://www.tucows.com/preview/194967/IrfanView?q=IrfanView

Brian

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/31/19 at 16:27:54

Thanks Brian, I downloaded the app.  Do you know how I can know the size to make it before I post the picture?  When I post a picture I can't seem to preview it prior to posting.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/31/19 at 17:08:48

I have a few more impressions as break-in progresses.

The "Big Betsy's" have a very linear sound with gain.  I had mentioned in another post that they don't seem to have the bloom of my HR1s and that's a good thing.  To use Steve's word (but maybe not his meaning), the sound is much more holographic, containing all the information across the entire volume spectrum.  Low level listening is completely satisfying since higher volume isn't needed to add density or weight to the music.

I don't have "holographic" soundstaging as far as I can tell, yet with these, the performers and instruments seem full sized.  The imaging is different too in that as I walk toward the speakers I seem to get closer to the performance.  From my sitting position I feel like I'm on the stage but last night, I was listening to Bruce Springsteen's "The Ghost of Tom Joad" and as I walked toward the speakers I seemed to come face to face with Bruce.

These have done well with every genre I've played but violin and piano are especially good - and real.  I can't say exactly how these are doing technically with the various frequencies, etc. (I think very well) but I'm so wrapped up in the music that I don't seem to care.

Title: Re: Steve's BIG BETSY Project
Post by ScottNC on 07/31/19 at 17:37:19

Arch,
Very exciting to hear and seemingly a good spot to be...
“Who cares what the technical specs are if they are sounding that good to you!”
All of you guys getting these up and going so quickly is really fun to see and hear about. Thanks to you and all for sharing the experience. As always, I can’t wait to see Steve’s next take on this project.
Best,
Scott

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/31/19 at 17:58:04

I reread Steve's posts of his Big Betsy impressions and I'd say that mine concur with his.  One thing I didn't see clearly was what extent if Steve uses the ZR2.  He talked about probably needing it for his Crystal-10 project.  I still find my version of the Big Betsy lacking when I bypass my ZR2.  This could all be taste, room, speaker position, etc.


Scott, I guess that's exactly my point.  It sounds so good that I don't worry about specs.   :)

Title: Re: Steve's BIG BETSY Project
Post by Lon on 07/31/19 at 18:10:32

You guys are making it hard for a guy to ignore the fun and enjoyment you're having with these! I may investigate getting a pair from Randy way in the future if I can get beyond all the hurdles I have in between though with already a spare pair of speakers or two (ERR and Traps) it's unlikely I have justification to do so!

I love fifteen inch speakers. My favorite amp for guitar and bass is a Fender Bassman "TV Fifteen" which is a heavy monster that has a 12AU7 in the preamp and a digital amplifier within, has the most versatile and useful sound for stringed instruments and goes very deep (and LOUD!) So I definitely know the appeal of that size speaker!


Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/31/19 at 18:30:24

In the late 50s my dad bought a Fisher 20W mono system and built a single 15" speaker.  I used it in college in the late 70s and early 80s and it was awesome!  I feel great security having big drivers again.  There is just something so right about them.

I feel a tremendous amount of gratitude toward Steve for all he's done but right now mostly for his ZR2 and Big Betsy design (thanks to Randy as well).

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/31/19 at 18:51:32

Arch, I moved the low boys back on top of my subs as a platform.  Lost much of the bass.  I was surprised but felt I gained back some detail and lost bass.  

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/31/19 at 22:41:12

Pal, like the picture you posted?  Did you have the F15s on the floor when you had better bass?  

Something unrelated I've been wondering is which tap ought to be better the 4 or 8 Ohm?  I've been running off of the 4 Ohm by default (used for my 4 ohm HR1s).  I typically don't hear a difference between the two but I haven't tried the 8 Ohm with these.  The drivers are rated at 6.56 Ohm if I read the specs right.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/31/19 at 22:49:56

Yeah like the picture but I moved the other OBs To another room and put the subs where they were.   The wizzer come is about at ear level now.   I’d guess that the wizzer is 30-33” high.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 07/31/19 at 23:18:01

I'm not 100% sure what your configuration with and without the better bass is but does more contact with the floor help the bass?  

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 07/31/19 at 23:20:03

Yes when they were on the floor bass was better.

Title: Re: Steve's BIG BETSY Project
Post by Lon on 08/01/19 at 00:29:17


Archie wrote on 07/31/19 at 18:30:24:
 I feel great security having big drivers again.  There is just something so right about them.

I agree. I grew up with a tube system (Dynaco) and full-range 12" EV speakers. Still can hear that wonderful sound in my head.

Title: Re: Steve's BIG BETSY Project
Post by Brian on 08/01/19 at 03:20:38

Hi Archie,
Lon's picture on this page of the green guitar measures 480 wide by 640 tall. So I think something on the order of 800 by 800 would be a comfortable maximum.  Anything smaller than about 300 x 300 is going to lack detail.  

Brian

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/01/19 at 03:44:29

MINOR SETBACK

I decided the other day that I was getting tired of unhooking my giant router from my table to cut holes in these speakers, so I purchased an inexpensive 1/2 inch plunge router from Menards. That pissed off the Audio Gods who were less than impressed with the laziness. As a result, when making my woofer cutout I flipped the wrong lever and instead of the the plunge router raising back up out of the board, it just dropped straight down through it.  Since I had my spiral bit shown earlier in this tread mounted in the router, it screwed itself at 20,000 RMP straight through the baffle, the plywood under the baffle, and my once perfect work table top. The table top is what really irritated me since it was a glass smooth perfectly flat poured finish without even a single mark on it.

So that's how my lunch hour went. I'll fix it, the wood has knots in it so I'll turn the damn hole into another knot. Remember there is little reward without suffering. Suffering points are hardcore, they always work and never loose their value.

For the same reason we don't show pictures of ourselves with our pants down, there will be no pictures posted of this incident either.

Steve



Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/01/19 at 15:51:34


Quote:
there will be no pictures posted of this incident

Coward!   ;D

I always say that it's not the never making a mistake that's important but the ability to fix it afterward.  


I looked at the label on the back of the F15 driver and it says the nominal impedance is 8 Ohms so I'm using the 8 Ohm taps on my ZMA.  Is it my imagination or are my output transformers running cooler now?

I'm listening to music I've had 45 years and and only now hearing it for the first time.  No BS.

Title: Re: Steve's BIG BETSY Project
Post by maddog07 on 08/01/19 at 22:49:13

1) to those experimenting with placement of their OB's on the floor .vs. on top of something.  The OB bible says that your baffle should contact the floor with no space, gaps, etc. between the baffle and floor.  This config. allows the floor to functionally extend the size of the baffle - i.e. mo' bass.

2) I experimented with spikes, etc. on my baffle bases... did not work for me - at all.  Sitting the base directly on the floor was way better.

3) and somebody was talking "isolation" from the floor with a base made with two boards with springs between.  for a cheap, easy and IME very effective solution - anti-fatigue foam mats work spectacularly for this purpose.  You can experiment with thickness (how many mats) or even use them in layers with other materials if you're adventurous and so inclined to go to the trouble and take the time.  This also builds on point 1 above in that the anti-fatigue mat acts as a "gasket" sealing your  baffle base to the floor, as well as providing isolation/dampening.

4) and for the person who was talking about the "image" being too low from a smaller height baffle - tilt them back a bit.  
for my smaller OB's, like Caintucks Betsy's - I built the base so that it tilts the baffle back about 10-15 degrees (depends on distance between baffles and listening position).  Tilting the baffle back to correlate with listening distance will raise the image.

To determine the amount of tilt.  Take a laser and affix it perpendicular to the baffle at the same height as the center of the driver.  Then put something reflective(sheet of white paper) in your listening spot/chair so that its roughly in the same spot your head/ears are when you're listening.  Then tilt the baffle back until the laser hits that spot - this is the angle you need.
I use the laser on my Bosch distance measuring tool (saw Steve using one of these at Zenfest a few years back - knew I had to have one immediately!).
https://www.lowes.com/pd/bosch-blaze-65-ft-indoor-outdoor-laser-distance-measurer-with-backlit-display/1000102525?cm_mmc=shp-_-c-_-prd-_-tol-_-google-_-lia-_-216-_-measuringtools-_-1000102525-_-0&kpid&store_code=2588&&k_clickID=go_1736136440_65430067662_338468225267_pla-433600879386_c_9023221&gclid=EAIaIQobChMIjrTGutHi4wIViZ6fCh2Izgn8EAQYBCABEgK0QvD_BwE&gclsrc=aw.ds
It aids immensely with "precision" speaker setup..!
;D

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 08/01/19 at 23:16:06

And if you want to go real cheap on isolating your OB's, run to your closest Home Improvement Center and pick up some water pipe insulation. It is a kind of foamy-Styrofoam tube material with a slit down the middle. $5 will buy more than you will ever need.
Slide it on and listen away.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/01/19 at 23:48:33

Maddog, I had about a 1/8" gap between my baffle and floor but with the platforms I put under them this effectively changed.  I'm not sure how isolation can be consistent with #1 even with a mat approach.

Is contact with the floor more of a no gap thing or a transfer of energy thing?  In my case my floor caused a bloating of the bass while the isolation tightened up the bass but didn't lessen it.  In my experience with foam type materials for isolation, they weren't particularly effective by themself (never tried anti-fatigue mat).  The frequency spectrum is too broad.


Today I tried an experiment and clamped thick pieces of wood on the back of the baffles to one side of the drivers.  The thought was to disrupt any side to side symmetry causing resonance.  I didn't hear a difference.

Title: Re: Steve's BIG BETSY Project
Post by Brian on 08/02/19 at 01:59:56

Steve,
I am sorry for the router trouble. I send you a blessing of cheer.

Brian

Title: Re: Steve's BIG BETSY Project
Post by slk23 on 08/02/19 at 02:36:17

Does it make sense to shape the baffle and place the driver so that there is more baffle below the driver than on the sides?  I'm thinking it would result in a good amount of bass since it'll couple with the floor while avoiding a reduction in the width of the sound stage that I've heard can result from a wide baffle.


Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/02/19 at 19:05:21

My very unscientific investigation with a stethoscope indicates that the top of the baffle has the bass.  Or it could be trapped there without the floor to take it?

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/02/19 at 19:19:44

I brought the F15 drivers to their knees last night.  I played the Koyaanisqatsi soundtrack and the title piece is super bass heavy with sustained bass notes.  I think they must have been tuned to the driver resonance.  At moderate volume it was fine but maybe a hint of low frequency buzz but at higher volume, the drivers made a frightening sound like they were breaking up.

Can someone explain what the driver resonant frequency, Fs, means in practice?  The F15 Fs spec is 50 Hz.

Title: Re: Steve's BIG BETSY Project
Post by Lonely Raven on 08/02/19 at 21:09:13


I used to play the Koyaanisqatsi laserdisc all the time back when I worked at a Laserdisc store. Loved that video.

FS is the natural resonant frequency of the driver and suspension in free air.  As you can imagine it's approximate (and I wonder if it's even measured anymore or they just let a computer tell them what it *should* be)

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/02/19 at 22:15:45

I don't know but the drivers must have gone into some kind of resonance.  I'm guessing the sound I heard was the coil touching.  

How's the weather over there?  We've had a lot of rain this side of the divide lately but beautiful today!

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/02/19 at 23:28:00


The ZMA should be able to bring the driver to it's knees at resonance, especially if it's sustained for any length of time.  When they rate the driver at 50 watts, you have to wonder whose watts and what damping factor did the amplifier have used in the measurement.  These are pretty low mass cones with a pretty tight voice coil gap so you either heard the cone rock causing the coil to rub, or you heard the voice coil former (tube) hit the back of the pole piece on the magnet.

Steve


Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/02/19 at 23:50:21

Fortunately, I haven't found another piece of music with that kind of sustained bass.

More than any speaker I've heard, these reveal the quality of the recording and performance.  It's like looking over the sound with a magnifying glass.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/03/19 at 04:04:27


A Big Magnifying glass ; )

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/03/19 at 04:36:18

In my room, the frequency balance of these speakers is so good that classic rock sounds like it should without any EQ. And I usually run the speakers without a ZROCK2, although it makes sound considerably better most of the time. Much of my listening is from the perspective of "what will a customer hear when he or she buys this or that in it's normal configuration..."  A ZROCK2 is so over the top, that it feels like serious cheating in so much as that once you have one, you can't not have one.

During the fest if I demo these (or any speakers) with a ZROCK2, since it has a bypass switch it is easy to hear it with and without... Problem is that from the very first time someone flips the switch to "on" no-one will like the sound without it. It will remain ON during the entire fest. Then when people, some who may not realize it was ON get home, order the a system without a ZROCK2 they will wonder why it isn't sounding the same.

For me a ZROCK2 is a dangerous drug. When it's on it makes everything sound 30% better than it actually is (recordings, not speakers and amplifiers) That in turn makes you think your gear is 30% better than it actually is to the rest of the world that has no ZROCK2. If ever you design a amplifier that needs a ZROCK2 to sound great, you've lost your spark.  This is why when I listen to a ZROCK2, it's only for a week at most and only periodically.

This will likely change soon enough as this new open baffle design with the Crystal 10 driver from Lii Audio will require the ZROCK2 to work in an open baffle speaker design on it's own. In fact I expect this will be a new and probably huge market for the ZROCK2. It's curves should fit perfectly with almost all passive open baffle speaker designs. I suspect these drivers with some break-in combined with this ZROCKED BAFFLE will be good enough to get that box of drool towels in the attic down for auditions.

Today I got both of the baffles finish sanded and have oiled the back sides of each. Still waiting for the drivers to arrive. Will design a base for these probably similar to the Big Betsy hopefully this weekend so I can post some more pictures!  I am also designing a high mass clamping system into the baffle to secure the drivers in place. When they cost a grand for just the drivers it's worth going all out to see what the true potential really is.  A few wood screws would work, but I can think of better ways to couple the energy from the frame of the driver into the heavy dense baffle.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/03/19 at 04:53:46

Archie,  I just had a vision about your speakers. I just saw a a pair of 16 oz brass weights screwed into the back side at the top where the vibration is highest (because there is no drain). Put them on either side situated on the rear face of the baffle, but just slightly off center, one more than the other. This will drink/drain the vibration as well as greatly lower the frequency.  I think you will have a different result than you did with the wood.  The weights could be heavier by perhaps several times, but not lighter.

It would need to be brass.  Although a lower density copper might also work well and give it a softer sound. Iron or steel would be inferior because they are so much harder.

I'm anxious to hear if Dan's MDF baffles have made any progress since his last post...  between the drivers being tight and new, and possibly using an  amp with too high of a damping factor it would certainly come off too dry and lean at first.  

Nothing would make me happier than to find out it was possible to get 80% of the performance and sound with simple MDF doubled up to 1.5 inches.  That would make it possible to have the Budget Big Betsy that countless people could have a lot of fun with.  Trust me, 80% of what I am hearing on my hardwood pair would way better than most speakers so it would be a win win win for every one.  

Happy listening!

Title: Re: Steve's BIG BETSY Project
Post by SteveB on 08/03/19 at 05:27:05

I am thinking about using 3/4" + 1" plywood for the baffles.  

I am also curious if the F15 would work in a half imperial.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/03/19 at 06:27:59


I'm pretty sure that using two different thicknesses would be superior to using to matching thicknesses in most cases.  As for the half imprerial, we have never tried a 15 inch driver in one.  Only 12 inch drivers.  Personally I think it would sound better in a Big Betsy Baffle than a half Imperial and a much simpler build.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/03/19 at 06:31:08



UPDATE 8/3/2019

I fixed the booboo and  as I mentioned got both baffle finish sanded and oiled on one side. Here is a picture



This is the back side.  I plan to mount the driver from the back with the cutout on the front side coming right to the edge of the surround.  The back side here in the picture is stepped to accept the driver and a high mass clamping system to hold the driver in place.  

When the oil dries, I'll be able to flip it over and do to the front side.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/03/19 at 06:42:08


It turns out that the American Walnut and highly figured Oak combo is greatly exceeding my expectations from an appearance perspective with the same linseed oil finish as the Big Betsy. These are going to be stunners. Without spending an hour on the picture, the picture is not going to compare to the real thing. There is nothing quite like solid, extra thick hardwood. The speaker could sound like shit and it almost wouldn't be a deal breaker because it looks so good. Of course the nice thing is that at least the Big Betsy sounds quite the opposite of shit so the experience is very elevated.  We anticipate this to be be even more intense.

Steve

Title: Re: Steve's BIG BETSY Project
Post by SteveB on 08/03/19 at 08:43:06

I was looking at some that were already built that are for sale. Thanks

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 08/03/19 at 16:52:06

I was looking at the Flagship Crystal-10 10" drivers on the Lii Audio website.  They are on sale for $999.  Based on the spec sheet, it appeared to have better low end bass performance than the larger 15" speakers so I emailed Leo to ask how the low bass of the high-end 10" drivers compared to the larger 15" full range drivers.  

This is what he said.....

Hi Jeff,

Without doubt the 10" is much more "full range" than any other drivers thus if your question is about how bass it can go,  10" does better and is more elastic.

We highly recommend a cabinet of 220L at least or if you want to play with OB,  the OB should be big enough to allow the most performance.

Best regards,
Leo ZHANG
Lii Audio Team


I am going to convert my Bubinga bass driver OB's to the Crystal-10 full range OB's.  I'll have a couple Baltic Birch plywood rings cut to allow the smaller 10" drivers to mount up to my Caintuck OB barrel shaped baffles.  

I don't need another set of speakers but I no longer have a use for my OB bass drivers anymore with my current loudspeakers.  Its a shame to see these beautiful Bubinga baffles unused.  I am hoping the Baltic birch will look cool with the off-white drivers and the darker Bubinga background.   Im hoping it will have a cool two-tone effect.  

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/03/19 at 18:17:10


Quote:
A ZROCK2 is so over the top, that it feels like serious cheating in so much as that once you have one, you can't not have one.


So true!  I don't know about the cheating aspect but my guess is that maybe 5% of recordings sound as good on the bypass.

Steve, can you clarify the weights location?  Are you suggesting they go stacked on the back or side-by-side but in either case with an asymmetric mounting?  The symmetry makes a lot of sense.  I was even wondering about a pair of baffles with the driver mounted 2/3 up and 2/3 out.

I do have a pair of big cast iron handles on the way already.

Title: Re: Steve's BIG BETSY Project
Post by deucekazoo on 08/03/19 at 18:17:38

"This is the back side.  I plan to mount the driver from the back with the cutout on the front side coming right to the edge of the surround.  The back side here in the picture is stepped to accept the driver and a high mass clamping system to hold the driver in place."

Steve, I was thinking of doing this with the 15". I noticed it has the gasket on the outside like a normal sub-woofer, so might as well use it. Do you think this would have any bad effects on the sound if it was mounted from behind because of the thickness of the wood? Maybe do a little round over on the front edge?

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/03/19 at 19:24:22

Now Steve has me looking for hunks of brass.  But what shape would be best?  It's expensive.  Bar stock is available.  Maybe 1/2"x1 1/2"x6" or would 1/2"x3"x3" be better?  Or even a thinner stock with a larger footprint?  At 1/2" thick, you need 6.25 sq in to make 1 lb.  Or some 2 1/4" round stock that weighs about 1 1/4 lb/inch.  I've also found thicker stock that I could get 3"x3" pieces out of at either 1 1/4" or 5/8" thick.  So many options!

Title: Re: Steve's BIG BETSY Project
Post by ScottNC on 08/03/19 at 21:20:36

you are right, it's not cheap... [smiley=10.gif]
Scott

Title: Re: Steve's BIG BETSY Project
Post by dank on 08/03/19 at 22:44:50

I've been listening to my MDF Big Betsy's now for a couple weeks.  The bass has gotten better, but is not bone crushing.  Actually, it's just what I'd expect from a 15" driver with an Fs of 50 hz in an open baffle enclosure.  It's going to be interesting to hear Decware's this October (just made my reservations 2 days ago).  Actually, when I think about it...if I have 1w running through these things I'm probably up in the neighborhood of 100db.  At that level, I would want at least 103 db and probably more like 106db of bass.  There's no way to get that, that I know of, other that turn up the power and somehow cut back on the audio that's not bass.  Maybe that's a Zrock2.  Like I said, I'm looking forward to Oct.

The amazing thing about the Big Betsy's, IMHO, is the HUGE sound stage.  They just fill the room like no other speaker I've ever had.  And that includes a couple of attempts with multiple front and side speakers in an attempt to get a bigger sound stage.

One thing I also noticed yesterday is this:  I have one song that has a couple of notes it it that can make you wince if everything is not perfect.  For a LONG time I thought it was the recording, but I've come to realize that a great speaker does not have an issue.  Probably has a lot to do with the amp too.  My recording of Norah Jones "Come Sail Away" has a couple places in the first 30 seconds that will tell me if I'm dealing with a great speaker or not.  The Big Betsy's sound as good as I've ever heard on that song.

Now for some pictures...First is a back view.  The handle/stiffener is a 2x4 and the base is built to take cement "patio blocks" to build up the weight.



I's using 2 patio blocks per speaker, that are screwed down with a cover piece of MDF.  This brings each speaker up to around 100 lbs.



The front view makes the top look wider than the bottom, but let me assure you it's not.  After seeing that pic, I went out and measured.












Title: Re: Steve's BIG BETSY Project
Post by dank on 08/03/19 at 23:07:12

Another potential source for material to make the Big Betsy Baffle is old bowling alley wood.  From what I can gather, its maple, anywhere from 1.5" to 2.25" thick, hard as nails, and a bowling alley just happens to be 41.5" wide.

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/04/19 at 00:44:15

Guys, a less expensive option is Rockwell dampening material. It is dense rubber with a foil topping, and is adhesive on back for easy application.  It helped placed on the back of the baffle, as well as dampening the speaker basket.
Also, if your base allows, stiffeners help too. All of this made a big difference With mine. I still have to order a few more pieces for my bass baffles.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/04/19 at 01:00:23

Geno, I don't understand much about open baffles -- I'm just following the crowd here but damping the baffle seems counter intuitive.  What Steve is suggesting will potentially break up resonances and "tune" the baffle vibration.  The brass won't damp anything but it will change the "stiffness."  Like how the stiffness of a spring changes it's natural frequency of vibration.  (I only said the latter in case you're not familiar with the physics.)  I could see where a baffle that has very little damping would throw more sound.  The stiffness of the baffle might change the nature (frequency spectrum) of the sound.  Keeping things asymmetrical might keep unwanted resonances at bay.

Dank, did you put that 2x4 across the top of the back for a handle or to stiffen the baffle, or both?  How much do those concrete blocks weigh?  I'm surprised your's are so heavy, even with the extra concrete.  Mine are 63 lbs.  MDF must be a lot heavier than maple.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/04/19 at 04:01:33



Quote:
I was looking at some that were already built that are for sale. Thanks


SteveB, Welcome to the forum!  You're in the right place.  Once these become available and for sale, this is where it will be announced first.  We may be able to take orders starting in October.

Thanks for asking!

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/04/19 at 04:08:28



Quote:
Steve, can you clarify the weights location?  Are you suggesting they go stacked on the back or side-by-side but in either case with an asymmetric mounting?  The symmetry makes a lot of sense.  I was even wondering about a pair of baffles with the driver mounted 2/3 up and 2/3 out.

I do have a pair of big cast iron handles on the way already.


I would place one in the hottest spot you can find on the back with your stethoscope.  Then I would see if there is another hot spot where you could put a second one.  I think you can lay it flat and play test tones allowing you to place the weights on the back and move them around to find the best result.

Install the handles first, they will change the top cabinet resonance pattern.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/04/19 at 04:13:32



Quote:
Now Steve has me looking for hunks of brass.  But what shape would be best?  It's expensive.  Bar stock is available.  Maybe 1/2"x1 1/2"x6" or would 1/2"x3"x3" be better?  Or even a thinner stock with a larger footprint?  At 1/2" thick, you need 6.25 sq in to make 1 lb.  Or some 2 1/4" round stock that weighs about 1 1/4 lb/inch.  I've also found thicker stock that I could get 3"x3" pieces out of at either 1 1/4" or 5/8" thick.  So many options!


When I saw it in the vision it was round, about 3 inches tall, about 2.5 ~ 3 inches in diameter, and had radiuses on both ends.  A hole in the middle with a bolt to adjust tension and there may have been a thin gasket of some sort.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/04/19 at 04:33:07


Geno's picture makes for a great opportunity to point out that the metal speaker basket on this particular driver is a week link in the speakers sound.  Damping it with the adhesive material is highly recommended.

There is really no reason that the sound that comes off the back should be any different than the sound that comes off the front other than being rolled off more in the high frequencies. Problem is, when the speakers are turned up the sound coming off the back has an edge to it that is completely missing from the sound that comes off the front. This edge is the metal frame resonance coming primarily off the flat area that the magnet it mounted on.

That is one issue, there is also another issue that could be easily resolved. The magnet is mounted to the frame with four or 6 points. Probably spot welds, maybe rivets or even screws. The metal is too thin to keep this from flexing. By making a 1/4 inch thick rope out of JBWeld epoxy putty and gently pressing it into the gap between the magnet and the speaker frame you will increase the stiffness of the entire structure by a factor of probably at least 4. And I guess if you're going to go that far, you should also consider self-stick felt stuck to the inside spokes of the speaker basket so that the sound from the speaker cone doesn't hit hard metal and reflect back into the paper cone.  

There are also discussions somewhere about making phase-guides for these drivers.  

Steve

Title: Re: Steve's BIG BETSY Project
Post by Brian on 08/04/19 at 07:58:37

Dan,
It looks like your driver is centered in the arc of the sides. Is that a true perception?

Brian

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 08/04/19 at 08:33:27


Steve Deckert wrote on 08/04/19 at 04:13:32:


When I saw it in the vision it was round, about 3 inches tall, about 2.5 ~ 3 inches in diameter, and had radiuses on both ends.  A hole in the middle with a bolt to adjust tension and there may have been a thin gasket of some sort.

Steve


Sounds like Eden Sound Audio may be a perfect fit.  www.edensoundaudio.com

Title: Re: Steve's BIG BETSY Project
Post by dank on 08/04/19 at 13:06:04

Re: Steve's BIG BETSY Project
Reply #324 - Today at 07:58:37  
Dan,
It looks like your driver is centered in the arc of the sides. Is that a true perception?

Brian

That's another photo angle issue.  Baffle is 42" high with center of speaker 25" off floor.  24" wide at top and bottom.

2x4 in back is both stiffener and handle.  Concrete patio blocks are around 17 lbs each (34 lbs total), MDF baffle is around 60lbs, speaker is a few lbs.  Total is close to 100 lbs.


Dan


Title: Re: Steve's BIG BETSY Project
Post by Donnie on 08/04/19 at 13:12:02

I wonder if instead of a solid hunk of a "heavy metal" that a container filled with a filler would be better?
I've stopped resonance before with lead shot, sand and even C-clamps with rubber between the jaws. Turn that vibration into heat!
In industry the general direction has moved to using viscous fluids for damping. The fluid is inside a sealed container that allows it to be adjusted to the correct damping level to quell the harmonics.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 08/04/19 at 17:38:27

This is an interesting description about vibration damping.
https://www.youtube.com/watch?v=VCxm3vTWgvU

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/04/19 at 17:54:15

I like Steve's suggestion about using the stethoscope to find the "hot spots" and applying weight there.  I'm still not sure that the object should be to damp vibration on the baffle but rather to tune it to a different frequency (which weights should do).  Each of our baffles (Steve, Dank, me) are different enough to have different resonance peaks.  I can't say that I hear any issues with mine but who can say for sure?

Searching ebay one can find brass disks of varying diameters and thicknesses.  The only problem is the cost.  I'm tempted to buy plate that I can cut up on my bandsaw.  If I don't mind wasting material I can shape the sides.  Easing edges and rounding corners might make sense even if I didn't go to the extent Steve suggests.

I do have a challenge generating test tones though.  Maybe I can download some or there might be a disk available?

Great video Donnie.  I really liked the model demonstration.

Edit:  I found this site.  They have a nice range of test tones.  https://www.demolandia.net/downloads.html?id=62182721

I've downloaded their 20Hz through their 17,000Hz.  Not sure I'll hear anything at the low and high end of the tones.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/04/19 at 18:19:24

I played around a bit with bypassing my ZR2.  I still don't like the idea that it's a "cheat" though.  I mean, if the ZR2 is a cheat then is acoustic room treatment also a cheat?  Afterall, Steve's listing room so so superior to anything most of us will ever have it makes the playing field unlevel already.

Anyway, A/B-ing the ZR2 is hard since it also offers overall gain in addition to the equalization but what I found is that without the ZR2, I still have the same bass extension but the bass seems thin and muted and my Big Betsy's also seem to have more of a bloom with extra volume (with the ZR2 my BBs are blooming at all volumes).  With the ZR2 it almost seems like I have an extra octave of bass but I think it's more just the extra fullness of the existing bass that I'm hearing.

If this were a competition to get there the hard way then the ZR2 would be cheating.  But it's not a competition and when an audio "shortcut" presents itself, use it!   ;)  In other words, if you don't have a ZR2, place an order.  This is as close to a sure thing as you'll ever get in this hobby.

This post relates to the ZR2 and the Big Betsy but I have the same bass experience with my HR1s and the ZR2.

Title: Re: Steve's BIG BETSY Project
Post by ScottNC on 08/04/19 at 20:38:15

I agree, call it what you will, I wouldn’t take my ZR2 out of my system for any reason, and if you don’t have one, again, totally agree, get one regardless. Room treatments too, these two things let whatever you’re running do it’s job in a far superior way! Cheers! Good listening, really enjoying this thread, post count and reads is over the top!
I can only imagine what the build list will look like this fall!
Best,
Scott
Got another few thoughts...
I can see adding another pair of speakers next to my DNA’s but it sure would be nice to have a DecWare speaker selector sitting atop my ZBIT and ZR2 [smiley=10.gif]

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/04/19 at 21:55:09

The ZSB ought to be able to be modified for speakers, wouldn't you think?

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/04/19 at 22:13:24

I played around with test tones and my stethoscope and as of right now, I don't see the need for brass weights.  My tones were: 20, 30, 40, 50, 60, 100, 200, 500, 1000, 2000, 5000, 8,000, 10,000, 15,000, ... Herz.

I honestly couldn't hear 15,000 Hz and I think it's me.   :(

I generally found the sound in the baffles to be relatively even except for with a few tones.  The 500 Hz tone peaked at both the top and bottom in the center.  This tone was by far the most prominent with any peaking.  I got somewhat of a peak at the top center with the 50 Hz tone and some peaking with the 40 Hz tone at the top edges in a zone about 6 inches wide from the top corner and down.  I plan on mounting heavy cast iron handles to the top centers so those reading may change.  The bass does seem to like the upper part of the baffles.

I also played around with my isolation platforms and interestingly, they don't seem to be needed at the lower frequencies but 200 Hz was interesting.  The top of the platform really liked that tone and got itself very excited!  I think a damping layer on the tops wouldn't hurt although the energy is small compared to the mass of the baffle and floor.  The energy didn't seem to get into the floor and I think my spring platforms perform mostly as expected.  From what I could tell, at worst, the platforms have a neutral effect with these speakers.  At best, they keep baffle vibrations from going into the floor.  

Getting set up to do this testing was a real PITA as I had to move my tower computer and monitor downstairs and hook it up to my AV amplifier (the Big Besty's are too big to haul upstairs without really good reason).  My equipment is of varying ages and not necessarily inter-compatible.  I'll have to see how motivated I am to do this again after my handles are installed.  It would be educational to see if anything changes.

Something else of note, the roll-off in the lower register is huge.  I had to turn up the gain for those test tones significantly.  I don't know how the bass can get enough boost without some form of equalization or sympathetic resonance to help.

Title: Re: Steve's BIG BETSY Project
Post by BAndrade on 08/05/19 at 00:41:48

To improve structural rigidity and redistribute center of gravity while making the structure lighter may I suggest the following for consideration:

-      Include I-beam braces running from the 2 X4 handles (on each side) to the a similar 2 X4 on the heavy mass horizontal footing. The web of the I beam can be much larger than the flanges (or the flanges eliminated altogether leaving only the web for a cleaner appearance at the back) since torsional forces if any are minimal if any when the speaker drivers operate.

Advantages:
o      This will reduce/eliminate structural resonance (not Fs the speaker drivers free-air resonant frequency) due to the added rigidity. Other wise it behaves much like a cantilevered structure with a heavy mass above the horizontal centerline which is prone to “singing” unless a very thick front face is employed making this large and tall speaker quite heavy. The triangular structure is heavily used in structural engineering to reduce weight thus cost, while increasing rigidity. Best of both worlds.
o      It will also enable the front baffle thickness to be reduced thus moving the center of gravity of the speaker structure as a whole further horizontally behind though still high up due to the dominance of the mass of magnet compared with the now a lighter front face. The front foot extensions at the bottom can thus be eliminated given a cleaner front look as the c.g. has moved back behind the fulcrum point (caution: tipping depends on how much the front baffle thickness is reduced as the c.g. is still high up and whether the speaker flange is mounted at the back versus from the front in). Tipping can also be avoided by simply attaching a couple of nylon straps at the back of the horizontal footing to the floor.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/05/19 at 01:28:32

Geno, that Rockville stuff looks like what I need to damp the tops of my isolation platforms but I can't find it in small quantities at a decent price so I might try some Bituthene roofing membrane.  I have rolls of that but it can smell.   :P

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/05/19 at 01:53:54

Adam, I got 2 sq ft on amazon, but don’t see it there anymore.

But I did find it here:    https://www.newegg.com/p/0UK-00ZW-00047?item=9SIAGNP8994622&source=googleshopping&nm_mc=knc-googlemkp-mobile&cm_mmc=knc-googlemkp-mobile-_-pla-audiosavings-_-mi+-+microphones-_-9SIAGNP8994622&gclsrc=aw.ds&&gclid=Cj0KCQjwhJrqBRDZARIsALhp1WSjQ5ujwIZqWFdDtIfmFyOPujurqDSIGZ9Vg-sikT-5YID8Cja-C4kaAlt1EALw_wcB

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/05/19 at 03:01:34


Quote:
I played around a bit with bypassing my ZR2.  I still don't like the idea that it's a "cheat" though.


When I say it's a cheat I specifically mean for ME -- and only because it makes my digital sources sound so much better I that when I'm voicing an amplifier or speakers, I would think "I've got it!" perhaps months or years before I actually did have it. This would cause me to send product out the door thinking I've got it and only a year later releasing updates for it. If the whole world had ZROCKS it would be great, but 95% of our and everyone else's products go out the door to homes that aren't going to have ZROCKS, or extra juicy tape machines, or even ass kicking vinyl rigs.

As the end consumer, a ZROCK2 is a completely different circumstance.  It simply makes your sources sound better, the way they should sound and for some reason rarely do.  Well, we all know the reason.  The post production process and the money spent on a DAC.  Most of us aren't sporting $30K DACs that actually sound good, so our digital does not sound like analogue.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/05/19 at 03:42:53


Archie,

When testing speaker baffle resonance or the sides of a speaker box, the frequencies are narrow. As an example, 400Hz might have no real drama, nor does 500Hz, but 417Hz might really light things up. The only effective way to test for this is to be able to slowly sweep the frequencies or step the frequencies 1Hz at a time.  Also you don't need a stethoscope always, you can use. your finger tips.  What you do need is stick-on dots that you can stick on the exact place where your finger tip was and write the frequency on the dot.  If you want to get documentative, you can glue a piezo tweeter diaphragm to the spots and hook the leads to an oscilloscope.
 
Many speaker cabinets I have tested over the years and some drivers themselves, have what I call an evil note, where if you hit it, and it sustains for any length of time, like a whole second, it will resonate and peak the frequency by 6, 10 even 12dB!!!! Just a single note in some cases. This is why some speakers sound so great until you play a specific recording with a sound that falls into that notch... Then suddenly your eyes squint, your neck cocks to the left and turns slightly...  then your palm finds your forehead.

And, as far as the weights, keep in mind it was a vision that flashed, but I agree with you it would take for example a 417hz peak on a board and move it down out of the audible range. Being of high density and mass it isn't going to turn energy into heat, but rather store/release/redistribute the energy.

I figured out right away with these Big Betsy baffles that they themselves actually become the wavefront, so if we look at the baffle similarly to the way we look at a speaker cone, we're just dealing with modal resonance patterns that are aggravated at certain SPLs. This is why it will be fun to see how baffles compare that are stiff sound boards, vs. energy traps.  

You can find frequency generators in apps for your computer or phone.  You can't rely on recorded tones, because you have to sweep the tones back and forth many times as you hunt down the vibrations, and then you narrow it and narrow it until you find the center frequency.  Usually in the case of a speaker box you put a brace in that spot -- which often doubles the frequency and drops the energy in half.  However, weighting it would make it more relaxed sounding and perhaps natural... so much audio gear has it's panties in a bunch from over execution... sometimes its nice to just ditch the panties.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/05/19 at 03:55:54


I got a few hours this weekend to work on these smaller walnut baffles and built the stands for the back. I'll dowel it up and make it all screw together with some 4-inch lag bolts / washers behind the buttons like I did on the Big Betsy.



I have done it enough times now (twice) to figure out that linseed oil will kick your ass if you don't open the doors...  It's a learning curve.

Steve




Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/05/19 at 04:15:42




So this is the first coat of linseed oil and after at least 24 hrs I'll do a second coat using steel wool, buff it after it dries and wax it.  Something about walnut that I have not found a finish that I like (poly/shellac/lacquer) because it makes it look fake, brings out a purple plastic veil that I can't stand, and that's amazing to me because I have never found anything that shellac didn't make look over the top good, except walnut.

The most impressive part of this build so far is actually the figured oak.  I purchased 20BF of this stuff for making tape machine sides, which I did, but now seeing it in the speaker, with just natural oil framed by the darker walnut I really couldn't be more pleased.  

BTW, the knots you see on this panel I actually painted into the finish because this baffle was knot free and the other panel is full of knots.  Hehe, that's the beauty of oil finish on hardwood... I can add more knots anytime I want... well within my patients to hand paint intricate wood grains because you can't just paint a knot anywhere you want.

So the next step will be to actually install the bases and front feet so I can stand them up in the shop.  Then I will focus on the esoteric mounting system for the drivers.  By then they should be here and I can lay the driver in the baffle and slowly craft something really trick to hold them in place with adjustable tension.  This way I can experiment with hard-coupling, gaskets, or even energy drains like a viscoelastic membrane.

While I wouldn't hate a larger radius on the opening I think this partial horn-loading of the cone will add some real attack.  We will see.

Steve

Title: Re: Steve's BIG BETSY Project
Post by ScottNC on 08/05/19 at 04:16:59

Nice

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/05/19 at 16:31:55

Steve, I think that frequency investigation is beyond me at this point.  My facility to pull that off is primitive, to say the least.  I am thinking about trying something I saw in a video.  A couple of the links have already been posted in this thread.  The engineer working with panel speakers determined that mounting the driver 2/5 and 3/5 off center and then mounting weights in the four quadrants in a 2/5 and 3/5 location helped break up resonances and reduce what remained.  He also said the total mass of the weights should be about 20% to 25% of the baffle mass.  I'm estimating my baffle at 50lbs so I'd need 10+ lbs of weight.  That would be roughly 3"Dx1"L weights, 4 per baffle.  Here is one video.  The relevant time start is around 21:30.  https://www.youtube.com/watch?v=zdkyGDqU7xA

The thing is, in his next video he claims that the reduction in the peaks was small and that blending panels with different peaks was a more effective method for flattening the frequency response.  (22:23 for:  https://www.youtube.com/watch?v=CKIye4RZ-5k)  But since I'm not building more Big Betsys and forming an array, the weights may be the only real option available.

All that said, I haven't found any bad tones in my listening sessions.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/05/19 at 16:47:12

You guys are digging into the resonance thing.  Interesting reading.

I haven't done anything regarding resonance thus far.  

I don't feel much overall resonance in the 1.5" MDF.  When I had multiple drivers in these baffles (before I cut them), there were times I felt I had created a giant tuning fork.  Its part of the reason I migrated away from them.  But I am not feeling (or hearing) anything too significant now.

Right now the low boys reside on top of my sub cabinets.  Center of the drivers are about 31" off the floor.  Too far in my opinion and it hurts the bass.  I may experiment with different heights, but in the end I may end up at the established 25" level.

I did spend some time with a laser measurement device precisely positioning them and it improved my overall imaging.  Based on that exercise, I would say these require exact positioning for the best imaging/soundstage.  Worth messing with in my case.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/05/19 at 17:52:57

Pal, I don't know how it relates to perceived bass but I hear the strongest bass in the baffle at the top when using a stethoscope.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/05/19 at 19:32:39


Quote:
When I say it's a cheat I specifically mean for ME


How ironic!  The Audio Gods demand a certain amount of suffering I guess.   :'(

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/05/19 at 19:48:22

At some point Arch, I will run REW to see how the response looks like vs my other OBs.  

I'll see what kind of peaks I have across the spectrum and then zero in on those to see if the wood is contributing.  

I won't alter these baffles any more.  They are just a temporary home until I build some proper ones.  

I have some Baltic birch leftover from my previous build.  I may double that up to see how it sounds and then decide if I go hardwood or not.


Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/05/19 at 21:47:51

I look forward to seeing what you get.  From the little looking I've done, Flat Response is a relative term.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/05/19 at 22:22:13

I have found its possible if you change the smoothing and/or the increments shown on the chart axis ;D

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/06/19 at 00:42:36

Mounting a heavy cast iron handle also smooths the curve.   ;)


Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/06/19 at 03:06:57

Well I did a quick and dirty REW measurement.  Pretty flat, really.

Nothing under 50hz

Dip at 175hz then flat out to around 3k.  Lower from 3-5k.  Drops after 12k.  Really drops around 14k.

I think part of the appeal of this driver over other single drivers is they can have a rise in the 3-5k range which can really be annoying on certain songs. This driver is actually down in this region.

With my Tang Band w8-1808s, I actually crossed them with an AMT at 1600 to avoid this issue.

Title: Re: Steve's BIG BETSY Project
Post by Brian on 08/06/19 at 04:43:45

Steve said:  
"Something about walnut that I have not found a finish that I like (poly/shellac/lacquer) because it makes it look fake, brings out a purple plastic veil that I can't stand."

This is so much my own reaction. Here is the answer I found.
I once redid an old shotgun stock by following the method recommended to me by a gunsmith. I will credit his name as soon as I remember it.
The method is: First make the walnut smooth with a cabinet scraper followed by steel wool down to 4/0. Mix Linseed oil and varnish half & half.  Wipe this on the wood and then scrub the wood with steel wool until wood dust mixes with the oiled varnish to form a thin paste. This will fill the pores. Now strike this mess off with a paper card or a stiff paper wad. Those hard surface paper napkins found in diners were recommended. This first application fills perhaps 20% of the pores. Let it dry overnight. Do it again tomorrow and perhaps as many as five times total.  The result has a wonderful silken feel. It looks nice, but somewhat satin. For a higher shine buff it with wax.

That oak is beautiful!

Brian

Title: Re: Steve's BIG BETSY Project
Post by Brian on 08/06/19 at 04:47:42

Phil Pilkington was the name. Brownells sells his ready mix of oil and hard drying varnish. I bought the Gold/Brown.  Except, I remember it being affordable 30 years ago! Although, that little 2 oz bottle does seem to go a long way.  I only used a small amount of mine on the butt stock of a double gun.  

https://www.brownells.com/gunsmith-tools-supplies/stock-work-finishing/wood-finishes/classic-gunstock-finish-prod9817.aspx

Brian

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/06/19 at 16:10:18

Brian, that's an old trick apparently.  25+ yrs ago my cabinet maker recommended a similar recipe he got from an "old" woodworker.  Great for an "oil" finish that needs to hold up with water present.

Another nice walnut finish is to use a gel stain (the gel stains have a lot of body and do some pore filling) with a wax top coat.  Wax also fills.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/06/19 at 16:15:27

Pal, that drop off at 14 kHz is consistent with what I found but I think my hearing is shot much above that.

Was there a lot of rolloff at 50 Hz or really nothing?  I get response below 30 Hz but rolled off after 50 Hz.  The drivers are surely moving so it would be the baffle, yes?

I think I'm going to try something with brass weights like I described above.  It will be a $200 experiment!   :-/

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/06/19 at 17:02:52

There is something there.  That was a flip comment.  Sorry.  

It rolls off gradually below 60Hz.  I'd believe you could hear something at 30hz.  If I had these on the floor again, they would definitely measure more bass.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/06/19 at 17:06:10

Okay, same as me then.  That's where the ZROCK2 plays its role.  It also enhances the lower to mid too -- fuller, juicier.  

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/06/19 at 17:08:07

Every now and again, I flip on the subs to fill in down low.  They integrate pretty well, but something is bothering me.  Until I figure it out, I have been fine with listening without those lower frequencies.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/06/19 at 17:34:25

I ordered 8 brass disks, 1 1/4"Lx3 1/4"D for rear baffle weights.  I found an on line supplier who had reasonable pricing and is letting me send them a USPS flat rate mail label.  That will save me over $30 in shipping.  The total with mailing is about $156.  That's a lot for what could be a useless experiment.  If the weights don't do anything positive I'll have a lot of paperweights.  I'll position them in that 2/5, 3/5 mode.  These will add about 14 lbs per baffle.

Title: Re: Steve's BIG BETSY Project
Post by dank on 08/06/19 at 18:10:10

Posted by: Palomino      Posted on: Today at 17:08:07
Every now and again, I flip on the subs to fill in down low.  They integrate pretty well, but something is bothering me.  Until I figure it out, I have been fine with listening without those lower frequencies.

I have subs in the corners, more or less, and the big OB's in front.  What's different is the sub's are now mixing with the audio off the REAR of the OB speakers, which is 180 degrees out of phase to what I'm use to.  Phase reversing the subs amp seems to solve the discrepancy.

My response seems to match yours, with "Nothing under 50hz".  Although I'd add "and darn little under 70hz".

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/06/19 at 18:14:51

Yeah, my first experiment will be to reverse phase on the subs.

Title: Re: Steve's BIG BETSY Project
Post by maddog07 on 08/06/19 at 18:26:59

Steve...

I've decided to skip Decfest this year!  Because I can already see it coming... if I attend, I will think I have to have a pair of at least one of these OB's you're developing.  Just what I need.. another set of speakers to add to the 9 pair I already have...!

Portable damping:
I have found these to be quite handy for numerous things... in addition to what I originally bought them for - my other hobby.
https://www.caldwellshooting.com/rests/shooting-rests/lead-sled-weight-bag-standard-4-pack/533117.html#start=1
you can fill them with lead shot, steel shot, sand. etc.  I've even used polymer beads if you want some damping/vibration absorption with less weight.  Once filled you can easily move them around and place them in different locations to see if adding mass/damping makes a difference and where it might be most effective.

For those of you contemplating brass products from Eden Sound - don't hesitate.  I had him make me up some custom brass footers with interchangeable feet - rounded (half spheres) and tall carpet piercing spikes.  He was nothing but professional, courteous and speedy.  He fixed me up with a set of footers that are a combination of his Radiused Bearpaws and his Deep Carpet Penetrators - I can change between the radiused bottom and the pointed bottom.

Mapleshade is also another source of brass footers/weights... I bought a pile of their products used off of Audiogon.

I almost always mount drivers from the back of the baffle, especially in my Trio baffles which use a secondary baffle/mounting plate to attach the driver/s to the main baffle.  This allows two things:
1) relatively quick changes of various drivers - just make mounting plates for each set of drivers.  I currently can run my Audio Nirvana cast frame 15's, 12" Alnico's, 8" Betsy's or a 8" Betsy W.O.W and Dayton AMT combo just by swapping out the drivers which are mounted to their individual mounting plates which are then attached to the back of the main Trio baffle.  If any of you have Hawthorne Audio OB's... you can likely do this.
2) you can play around with the "tension" that the driver is mounted to the main baffle with.  Kind of what Steve is talking about making rigid clamps to hold the drivers to the baffle.  With the Hawthorne Audio Trio mounting method, you can vary the material between the driver, the baffle and the mounting plate, as well as the tension/how tight you attach the driver/mounting plate to the main baffle.

I have typically followed the original designers(Darrel Hawthorne) practice of isolating/damping the driver/mounting plate from the main baffle.  I have used various materials between the back of the main baffle and the driver mounting plate and sometimes even between the mounting plate and the driver.  I tend to try/experiment with whatever I might have laying around the shop leftover from other projects.
I have used closed cell neoprene foam, cork, Hush Mat https://hushmat.com/ (a product similar to Geno's Rockwell stuff), Corian-like hard-surface cabinet top material, masonite, concrete foundation gasket material (a heavy duty closed cell foam), particle board, OSB... whatever leftovers from other projects I might have laying around that looks interesting.  No point in hauling the stuff to the dump if I can find a hobby use for it.

Just my experience, everyone else's may be different, but attaching drivers directly to baffles has induced very undesirable buzzing/resonances that originated from various places on the baffle. And this was with my Trio baffles which weigh over 100 lbs and have sand filled side rails and are covered with two layers of felt front and back.  I suppose with enough experimentation, you could take advantage of this resonance if you can get it tuned to a desirable frequency and at an appropriate level.  I've had better luck (and faster) damping/absorbing/moving/reducing/draining away the vibration/resonance that caused the audible buzzing of the baffle structure.

You can get cork from Bangor Cork - https://www.bangorcork.com/
you can get high quality cork from these guys in all kinds of thicknesses, widths and lengths, rolls, etc.
I have purchased sheet and roll cork from these guys in various thicknesses - good product, fast service - no hesitation.
I use a layer of cork on top of all the shelves of my equipment racks.
The manufacturer of the Betsy drivers recommends cork on the back side of an OB baffle.  I have seen it mentioned it other OB designs as well.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/06/19 at 18:32:05

Steve had the phase reversed when he used his BBs as subs with the Bestys.

What might be a typical frequency for bass in most music?  I read the bass guitar goes just under 50 Hz.  What about a bass drum?  Or for orchestral music?  I'm trying to get a feel for the bass I'm getting with my ZR2 bypassed.  It's not nothing but maybe my frequencies are skewed?  I don't have a way of measuring.  Got any song examples?

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/06/19 at 18:32:54

Too bad you are skipping MD.  I'd like to hear your thoughts on these drivers vs others you have used.

Thanks for the cork source.  Seems like reasonable pricing.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/06/19 at 18:41:14

I mostly notice the lack of bass in electronic music like Daft Punk.

I don't think my Eminence drivers went much below 50 either.  That's where I have them crossed with the subs on my other OB speakers.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/06/19 at 18:57:19

I have my drivers mounted from the front and directly to the baffles.  I haven't noticed any buzzing but it'd be easy enough to slip a thin layer of cork behind them.  What are others doing in this regard with the F15s?  I wouldn't want to mess up any beneficial coupling either.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/06/19 at 19:38:48

Mine are directly to baffles as well.  I have used various materials in the past.  Rubber, gasket sealing tape, rope calk, etc.

Its kind of a listen and see what you think situation.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/06/19 at 21:12:52

I'll leave it for now.  I covered the underside of my isolation platform tops with the Bituthene (viscoelastic with a plastic membrane on one side) and they still resonate.  Just a different frequency.  Damping is hard to get when you want it.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/06/19 at 21:25:26

Remind me Archie, are you 3/4" MDF?

Title: Re: Steve's BIG BETSY Project
Post by Lonely Raven on 08/06/19 at 21:53:08


Quote:
Every now and again, I flip on the subs to fill in down low.  They integrate pretty well, but something is bothering me.  Until I figure it out, I have been fine with listening without those lower frequencies.


Too bad you no longer have a Raven around to help you figure those issues out...

I was listening to Daft Punk last night in my dining room, full of boxes and bins still as I'm still unpacking, and that one bass note that usually drops hit just so nicely in this little room! Nothing but DS, Zen, El Camino.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/06/19 at 21:57:39

I'll expect a fully treated listening room by September with separate AC line, diffusers, bass traps and a IKEA listening chair ;)

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/06/19 at 22:07:35

1 1/2" hard maple butcher block.  If you meant the platforms, they are 3/4" plywood.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/06/19 at 22:22:07

OK, I got builds mixed up and was too lazy to go back in the thread.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/07/19 at 03:56:27


Tonight I was able to get the bases assembled so that the speakers can stand upright. Walnut is a really soft wood apparently, because I scratched the crap out of one side just sliding it around on my somewhat soft workbench top. I had to sand out almost the whole thing... this is a nice thing about oil, you can go in and repair things like that without too much trouble.



Archie, just for you, if you look carefully on the table top next to the hammer is a perfect 1/2 hole that matches the one in the baffle that I've sense plugged. I haven't decided if I'm going to leave it like it is and tell people it was a bullet hole, or turn it into a knot. I spent about an hour hand-painting knots on the second baffle to give it a better match to this one (I know, ballsy right?)

I'll post a picture of that once I get the finish repaired from having to sand out all the scratches. BTW, the oak doesn't scratch. It drills and cuts like cast iron, while the Walnut cuts almost just like pine.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/07/19 at 04:04:31



 
Like the Big Betsy, I just put stainless lag-bolts in from the back side to fasten the front feet which are also dowelled so it's easy to remove them.  These bolts are hidden from view because they are behind the rear base.  The rear base is attached the same way with the bolts being hidden behind the plugs in the front.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/07/19 at 04:10:26




It's got a good meaty look to it.

Steve


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/07/19 at 04:15:18




A nice picture in the natural sunlight from the window when the lights are off.

Still waiting for the drivers.  I'll work on the finish while I wait and then once they are here, will work on three large hardwood clamps for each driver to hold them into the baffle.  That's probably going to be bitchy since I'll want a radius to match the cutout - a safe assumption anyway since I don't even know how I'm actually going to do that yet.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/07/19 at 04:32:27

Also on an interesting note, I have been finding myself really missing the "hit" from the F15 drivers and despite the insane imaging of the array and the top end, I think I'm going to re-install the F15 drivers back into the Big Betsy baffles already.  I enjoy listening to Randy's baffles he made for me by themselves with of course a wider placement.



I can create this same exact soundstage with only the small baffles, simply placed  farther apart with more toe-in. The lower registers can be easily put into the mix with one of Randy's subs which are small and easy to overlook. How do you think this soundstage happened with the Array? Certainly wasn't from the 15 inch woofers that don't go much past 500Hz ; )

Anyway, getting back to the switch over back the the F15 drivers -- I wasn't really expecting to feel this way so soon, but it's probably going to happen tomorrow afternoon. The array is really good, but since it uses a low-efficiency high roll-off woofer in the Big Betsy baffle, while nice, it pales in impressiveness to the F15 fitted Big Betsy baffles. I've never heard an open baffle sound as good, so I have to go back to having it again.

You could get to 95% of this exact result with a pair of Randy's subs driven passively with no additional amplifier, as I did here... so as I mentioned before I feel like using the Big Betsy baffles as the bass modules for this array is a total waste of hardwood.

Steve


Title: Re: Steve's BIG BETSY Project
Post by Brian on 08/07/19 at 04:32:32

Looks great!

Brian

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 08/07/19 at 05:53:49

I have a pair of the Lii Audio Crystal-10 Flagship drivers (10") on order.  These will replace the 15" Hawthorne Audio "Augie" bass  drivers in my Bubinga Caintuck Audio OB's.  I ordered a 3/4" thick Baltic Birch plywood ring from www.craftcuts.com which will be cut to my specs to allow these 10"  drivers to mount up to my Bubinga baffles.  I will treat the rings with Linseed oil, then beeswax in Caintuck Randy fashion.

These will become the new speakers for my ZMA.  They are pricey but I have a really good feeling about these drivers from Lii Audio.  

Title: Re: Steve's BIG BETSY Project
Post by ScottNC on 08/07/19 at 06:04:16

Those are beautiful speakers Steve. They definitely have a stout look.
Scott

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/07/19 at 15:32:13

Stunning work Steve.  Very rich looking.  Thanks for sharing the build notes/pictures.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/07/19 at 16:45:46

Steve,

Your observations about walnut indicate why it has traditionally been one of the woods of choice for furniture (along with mahogany).  It is soft enough to work easily and is also well behaved.  

I think you ought to highlight the table repair.  A paduk plug would have been really cool!

I reread an earlier post in which you said the heavy bases were needed for vibration drain.  I missed that comment when I built my BBs and my bases don't support the baffle bottom edge like your's do.  These new baffle bottoms look like they may be overkill.  It might be just my aesthetic though and have nothing to do with audio qualities.

Of the three full sized BBs on this thread, you, Dank and me, we seem to all be hearing very similar things but how are we going to figure out how critical baffle material, thickness and exact design is to the sound?  I've never made speakers before and the vibration thing is so complex that I'm starting to think it's witchcraft!  I've been told that, by theory, these should start rolling off at 300 Hz.   :P

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 08/07/19 at 23:27:03

Well, my "Crystal Betsy" project has officially begun....

I got notice that the Lii Audio Crystasl-10, 10" full range drivers I ordered shipped today from Lii Audio via UPS.  Not sure the transit time.  

I removed (sold) the 15" Augie bass drivers from my Bubinga baffles.  I ordered a 16" outer diameter/9.85" inner diameter Baltic Birch plywood ring to attach to the baffle in order to the Crystal-10's.

I used to have my DM946's sitting on top of these twisted wood pedestals (see pic below).  I'm going to mount the baffle base to the top of these pedestals using large threaded brass weights I purchased from Eden Sound.  I will drill four holes from the top of the baffle base down into the top of the wood pedestals.  I will then use four threaded nut inserts in the pedestal to take the 1/4"-20 all-thread rods that will be attached to the brass weights.  I am essentially going to screw down the brass weights from the top to couple the baffle base to the pedestal.  This will put the drivers at ear height when I'm seated.  Hope to have everything done in the next week or so.  




Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/08/19 at 00:46:50

My F15s shipped from a California warehouse so you might have your Cr-10s soon.

Title: Re: Steve's BIG BETSY Project
Post by Brian on 08/08/19 at 03:55:52

Quote:
"What might be a typical frequency for bass in most music?  I read the bass guitar goes just under 50 Hz."

Hi Archie,
The lowest note on a treble guitar is 80Hz if it has standard tuning. To me, that is a very bassy note. When a bass guitar plays it's 50Hz note, that of course is the lowest note on the guitar. Most of what we hear from a bass guitar would be higher than that.  

Brian

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/08/19 at 04:50:15


Tonight I restored the Big Betsy to the F15 drivers and was feeling the energy in the baffle itself...  My take away is how incredibly stiff and fast the wood feels.

Archie, the energy is highest at the top of the baffle because that is the farthest point from the drain/floor. This is why the handle makes an audible difference. I can still remember taking the handle off one of Randy's baffles and the sound became less pleasing. I put the handle back on and the sound became great again. Incidentally the handle you purchased is the same one I used on the Big Betsy's I built, anything less would be inadequate... except for Dan's solution of a large brace : )

Also on another note, the Crystal 10's arrived today!  They look nice.  Will probably be a week or so before I get to install them, but I'm sure it will be worth the wait.

-Steve







Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/08/19 at 06:25:23


Had a demo tonight, and Daft Punk was requested, which sounded very good, the particular cuts that were played, and it made me want to hear it again after they left, but turned up a bit (which I should have probably done during the demo). So off I went, with the newly restored Big Betsy /F15 combo and I wasn't disappointed. Then about an hour later after a nice break, I realized I have that album in 200Gram pressings that I haven't even heard yet. I started with side 3 and 4 and to be honest it sounded a bit heavy and a bit dull.  In some ways the digital sounded better, crisper. I was thinking boy, this pressing isn't really all that great, I've certainly heard a lot better on my vinyl rig before... Then I played side 1 and 2 which were noticeably better, but still all night with this album there was a slight bloat in the mid-bass making an otherwise stellar sound a little less stellar.

So, a nice hour of listening but I've heard better... then the last song on side two, I had the idea to turn up the volume. Now keep in mind it was on 9 out of 10 already, and I was simply amazed all evening that the amplifier never clipped. Anyway, I'm using the 25th Anniversary Zen Triode 2 watt amplifier driven directly from the phono-stage which is why it's so amazing to hear music this forceful and room filling with no clipping. It would in fact be an accomplishment for even our 40 watt amp. Anyway, I turned up the volume 3dB to max and the amp still wouldn't clip. Sounded better in fact, the bass starting to tighten further. About that time I decided to check the bias switch on the front to see which setting it was in, and it was in the soft setting. I turned it to the hard setting and the amp just began to clip, so I backed the volume back one click and sat down.

The sound after this adjustment was transformative. The frequency balance became perfect, everything locked in. The energy was intense, I could feel it in my chest and bones yet the music wasn't any louder than before, it just had so much SERIOUS CRUNCH to it, that I was simply stunned.  First I couldn't believe how good the pressing was that an hour ago I thought almost sucked. But mostly, just the incredible sound and dynamic expression with perfect balance made it expressively clear that this combo, the 25th Anniversary Zen Triode amplifier and the Big Betsy baffles at 100 real dB have more hit, more crunch, more scale, more slam, and do it in a more gracefully way than any combination I have heard to date, including my reference full-range Electrostats with servo-charged 5000 volt tube amps. It is just unbelievable. And it's just unbelievable how in the same night on the same gear you can rate an LP pressing only a 6 and an hour later after flicking one switch, rate the same pressing a 10++ not to mention it sounded like someone came in a put better speakers in the room.

I have listened to Daft Punk, and lots of really hard hitting disco music with our bigger amps on virtually all of our speakers over this many years and it's always brought big smiles to my face, but now I'm still too shocked to smile because I am hearing this anniversary edition 2 watts spank the ass of every Decware amp ever made except for the ominous OTL of which only one exists in the universe.  When I say spank the ass of, I not only mean sound better, I mean hit harder, I mean get louder, I mean sound bigger, I mean exhibit less compression, I mean do it with ease.

This really makes me wonder what would have happened had these drivers been available 20 years ago and of course these magic shaped baffles. I can literally see Decware having evolved around one amp and one pair of speakers because it's that good.  I don't know how it does it.  I defys all logic.  

Trust me, this years DECFEST 2019 / first weekend in October is going to short everyone out so bad they're not going to know what hit them.  Between the amp and the speakers it will be like seeing a UFO for real, because it's just that incredible.

Also after listening tonight I realized another good name for these speakers would be "CAPTAIN CRUNCH".

Steve

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 08/08/19 at 07:02:01

I took a look at the tracking number and it was in fact generated in the United States, so that is a great indication it is also shipping from that California warehouse.  Should have these drivers end of week or first thing next week. Either is fine since my custom wood mounting rings will not arrive until sometime next week anyway.  I have the mounting hardware ready to go so hopefully will be playing music through these Crystal-10's by Friday of next week.  

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/08/19 at 14:53:10

I figured out what was off when I was trying to use the subs.  The cross-over was set too low and there was a hole in the sound as a result.  I tried different crossover points and the one which sounds best right now is 83Hz.  Higher than I expected.

I also tried the bias switch in the other position with Daft Punk.  I liked what I heard.  I did also turn it up a bit and that helped bring out more details and slam.

I do think that these drivers should come with a warning label: your 2 watt zen amp will drive these speakers without distortion into the 95+db range and you may not notice it.  Please use caution when rocking out.

Title: Re: Steve's BIG BETSY Project
Post by ScottNC on 08/08/19 at 15:00:40

This thread just keeps getting more and more enticing by the day.
Not being familiar with Daft Punk, I pulled down what looks to be about a hundred of their “main” songs into a Tidal playlist. Steve or anyone familiar that would know which songs he’s referring to, please let me know as I’d like to listen to what he was listening to last night so I can get a better feel for what he’s describing, even though it’ll be through my system, which, ain’t all that bad!  
Thanks,
Scott

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/08/19 at 15:09:06

The album I was listening to this morning was Random Access Memories.  The tracks which I felt best demonstrated the effect were Giorgio and Instant Crush.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/08/19 at 16:42:26

It's funny that I ended up with the same handles considering where I started my search and where I ended.  I bought from this ebay seller ($13.50 for 2!).  I buffed them with a wire wheel on my grinder.  I had to ream the holes for my #12 screws and I remilled the counter-sink.  I then used "gun bluing" to blacken them and finished with a coat of oil.  They are nice and beefy!  https://www.ebay.com/itm/Pair-of-9-Large-Rustic-Handles-for-Barn-Door-or-Gate-Pull-from-Antique-Design/173389877363?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

I'll try my BBs off and on the isolation platforms again.  I didn't notice much difference when I first took them off of the floor -- which theoretically reduced the "energy drain."  Once I have the back weights attached (they've shipped) I'll try some combination of things.  I really don't expect to hear much difference.  When I put the handles on I thought I had a reduction in volume but I took one off and couldn't hear a difference between speakers.  This is likely all just me.

I don't have any Daft Punk but a great album for me is The Who's Quadrophenia.  So much sounds fantastic on these but also Jean Michel Jarre's Electronica series also stand out.  For more of a classical genre, Max Richter is sublime.  All vinyl, of course.  Listening to Palomino's Daft Punk tracks on my computer speakers I can get and idea of what they must sound like on the BBs.   Alan Parsons Project comes to mind and is also incredible on these.  The "annoying" disco beats actually sound good!   ;D


Brian, thanks for the bass info.  I have a feeling that bass generally doesn't go a low as speaker specs might suggest (unless by some kind of harmonics).  I wonder what the frequency is of those bass beats on so many dance type tracks?

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/08/19 at 16:57:01

Thanks for the link Archie.  I will use that in my build.  I may go get wood this weekend.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/08/19 at 16:58:54

I offered him $13.50 and it was automatically accepted.  You could try lower.  I did file them a bit.  This guy must do some casting and they come as right out of the mold practically.  Great value though.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/08/19 at 17:01:35

I offered $12.  We'll see.

+1 on Quadrophenia.  I have it in both vinyl and CD rip.  I have listened to that album a lot - mostly when I was young.  But now I'll have to listen to it with these drivers.  Maybe even break out the TT.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 08/08/19 at 17:11:48

I've been watching this guy on YouTube who saws up live edge lumber, lots of walnut that is in the 2" thick 35" width range.. Hmmm??
It sure could be purdy.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/08/19 at 17:20:05

I listened to it last night and I heard the guy walk from left to right across a shingle beach.  I could hear the rocks crunch under his feet.  I've listened to this album for 45+ years and never heard that before.  Or at least I never noticed it.  There is a difference.  Once I "hear" something with a better set up I can go back and find it was there all along but somehow never came into focus.

Donnie, I have a huge 2 1/2"+ slab like that and I had the same thought.  A pair of speakers would be immovable!

Title: Re: Steve's BIG BETSY Project
Post by dank on 08/08/19 at 19:51:32

Here is a really nice depiction of the frequency's generated by different instruments, including their overtones:

http://csgtech.blogspot.com/2012/07/sound-source-frequency-ranges.html

If you "save image as" and then open with a picture viewer and print you should get a nice reference if you ever wondered what frequency it was.


Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/08/19 at 19:58:32

Thanks Dank.  I have seen this before.  I thought there was a key though that referred to the bar colors, like first harmonic, etc.  Am I just missing it?

Edit:  I see it now.  Its in the bar for the male voice at the top.

Title: Re: Steve's BIG BETSY Project
Post by ScottNC on 08/08/19 at 20:21:03

Thanks Dank👍🏼

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/08/19 at 20:50:11

I guess there is a lot of sound that lives down there!  I did not realize a piano went that low.  I have a 6'-1" grand in my LR and I had no idea that the lowest note was below 20 Hz.  I assume all pianos play the same range regardless of size.

Title: Re: Steve's BIG BETSY Project
Post by lazb on 08/08/19 at 21:35:12

Bosendorfer Imperial plays a full octave lower than the standard 88 key piano.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/08/19 at 21:40:01

How's it manage that?  Does it have 98 keys?

Ha ha, I just looked it up and it has 97 keys.  That gets into seismic territory!

I also found a nice chart that gives the frequency of all the notes.

https://en.wikipedia.org/wiki/Scientific_pitch_notation

Title: Re: Steve's BIG BETSY Project
Post by lazb on 08/08/19 at 21:55:40

Here is a link to some Bosendorfer recordings from Delos so the sound is great!
https://delosmusic.com/artist/carol-rosenberger

She is associated financially in some way so I have always assumed that had an influence on her being recorded by Delos on her own personal Bosendorfer Imperial.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/09/19 at 02:24:33

Well I bought some wood tonight.  Six 42” red oak stair treads at $26 each.  I paid another buck apiece for precision cuts to take off the roundover and make them 10 7/8”.   Total cost was about $175.

They are a little over an inch thick so not the full 1 1/2” you other guys have so we’ll see.   If I get some time this weekend I will glue them up and maybe break out the router on Sunday.   If I don’t screw them up I’ll have baffle similar in size and shape to Steve’s.  Just won’t be as thick and heavy.


Title: Re: Steve's BIG BETSY Project
Post by Lonely Raven on 08/09/19 at 06:47:36


Quote:
Once I "hear" something with a better set up I can go back and find it was there all along but somehow never came into focus.


I posted a page a long time ago that showed an experiment that I used as an example of why it's so difficult to A/B stuff, even blindly. In the experiment there is this soundbite of crazy hash/white noise and buried in there somewhere is a voice...you simply can't hear anything but hash. Then they have you play the same track with the woman's voice brought slightly to the forefront. From that point forward, now that you've heard the woman's voice, you can go back to that first file you played and the womans voice pops right out!

Basically your brain remembers that audio pattern and fills in the blanks for you when you listen to the first buried voice track.

Steve and I have talked about this with harmonics and such. I hear people all the time saying "I'm too old to hear that frequency so why bother", or in my case I have a bite taken out of my audio spectrum, and I'm probably not hearing much past 15k anymore...but I still have amazing hearing. It's not because I have "Golden Ears", but because the I have a good processor (brain) recognizing patterns and filling in the blanks.  

That's also why I think it's so very important to hear music live, and expose yourself to as much music and sound (in general) - You need to sample those patterns so you *know* what they sound like and develop your audio palate.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/09/19 at 14:11:39

Any tips on starting the radius cut?

Had a great listening session last night with the bias switch in the "up" or high position.  Listened to this playlist.  Nice pop to the guitar strings.  I especially liked Feel Good Inc.

https://tidal.com/browse/playlist/ceefef60-4ccf-44e4-a6ac-ebb7d5c3f524

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/09/19 at 16:12:14

You are cutting with a router?  If so, just take shallow cuts (1/8") and watch that the drop doesn't break off when the cut get close to done.  If you have a band saw then cutting before it's all glued up works well.  Either way you'll probably spend more time setting up and making jigs.  Oh, I fortunately drew center lines on my blanks before I cut the radii.  Once they are cut it's hard to locate yourself on the barrel shape.

That's going to be a nice baffle.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/09/19 at 16:15:54

LR, still, it's disconcerting to listen to test tones and suddenly find the point where they go "silent."  But since music isn't made out of test tones, your point about the harmonics makes total sense.  Nevertheless, it's amazing how good these F15s sound despite not going very high.  

Title: Re: Steve's BIG BETSY Project
Post by Rivieraranch on 08/09/19 at 16:20:08

I, too probably can't hear higher than 14,000 Hurts but I enjoy music a lot.  

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/09/19 at 16:49:42

Thanks Archie,

Yes, I have a router.  I may do an initial cut with another saw to take off all but the last 1/2" so I don't have the issue of the residual breaking off.

I am assuming you started at one end and went in the direction of the router spin.  

I do think the setup will be the tough part of this.  I fully intend to do a practice run on both the radius and the driver cutout.  Its quite the bummer when your driver cutout is just a touch too small.

I went through about 30 treads to select 6.  Hopefully the grain will come through.  I am still deciding on a finish.  I doubt I will do anything too fancy the way I go through baffles.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 08/09/19 at 17:15:20

Palo,
Shellac is the only way to finish oak. Maybe 3 or 4 coats of Amber Shellac will make it pop.
Quick and easy.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/09/19 at 17:58:37

I never can remember the direction to go on the inside or outside of a template but I think you'll go left to right for the arc and counter clockwise for the driver hole (if you're using a bar with a fixed pivot point then it probably doesn't matter what direction you go).  I used a circle guide that I made and a bushing on my router to cut that.  I found 14"+ (under 14 1/16") fairly optimal.  I had just a skosh of play when I placed the driver.  Too big on the hole and the screws won't have much to bite.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/09/19 at 18:09:06

Donnie, does shellac come in black? :)

Archie, I find that my router cuts are much better when I go in the direction that the bit is turning.  I discovered going the opposite direction to not work well at all on ply.

I was going to flush mount the driver, but it sounds like I better be pretty careful with that or just surface mount it.  I have missed on that cut as well and not had enough for the screws to bite into as you said.

Title: Re: Steve's BIG BETSY Project
Post by deucekazoo on 08/09/19 at 19:03:30

"Donnie, does shellac come in black? Smiley"

Palomino, I hope you are joking with that one!

I have had good luck with Sparathane on red oak, well doors mainly. It gives it a nice golden oak color with really good protection.
Also if you are worried about having enough material for your screws look into hurricane nuts, Parts Express sells them. Then you just use machine screws to hold your driver. I have been using these for years.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 08/09/19 at 19:08:59

Alright let's discuss climb milling vs. conventional milling.
Climb milling is where the cutter "pulls" itself into the material, the router seems to power itself.
Conventional milling is where the cutter "pushes" back to you, the router takes more pressure to cut.
Climb milling will give you a cleaner cut because the chip is thinning as you cut along, but it is much less forgiving. Your setup has to be rigid and you have to control the cut better because it is easy to over feed the cutter.
Conventional milling is a little more forgiving but causes more heat because the chip is thickening as you cut.
Sharp tools are your friend, so sharp that you cut you eyes looking at them.
I could get real technical, but I'll save you the agony.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/09/19 at 19:24:44

Thanks Donnie,

I was teasing about the black.  Most of my stuff ends up black to hide my incompetence.  If my work is clean, I stain/poly, etc.

On my last set of baffles, Raven and I did a good job cutting only for me to sand through the top layer of the baltic ply near the cutout in an attempt to remove swirl marks.  Love the baffles with the grain showing, but they will eventually be painted black.

10-4 on the climb vs conventional.  Most of my screw ups have been doing conventional.  Seems that digging in can be rough on ply.  I haven't had the same issue with MDF.

And on the hurricane nuts, I think I have some but the bolts for those take more room on the lip than wood screws.  Maybe I am thinking of the wrong thing.

Title: Re: Steve's BIG BETSY Project
Post by deucekazoo on 08/09/19 at 19:46:28

Palomino, I think you are thinking of the correct ones. They do take more area up. You have to drill the hole larger to install them, but then you use machine screws and can take the drivers off and put them back on without worrying about the wood wearing out. The hurricane nuts have a back plate to them so when you screw something down you are not only pulling on the thread but also on the back of the wood. They are different than just brass threaded inserts.

Title: Re: Steve's BIG BETSY Project
Post by deucekazoo on 08/09/19 at 19:50:55

Hurricane nut

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/09/19 at 19:53:16

I have the machine screws that you use the allen wrench to tighten on my cottage baffles and on the ones that I used for my low boy temporary baffle for the F15.

I looked up hurricane nuts and that isn't what I have been using.  I have been using these:  https://www.parts-express.com/1-4-20-deluxe-6-prong-t-nuts-50-pcs--081-1090?utm_source=google&utm_medium=cpc&utm_campaign=pla&gclid=EAIaIQobChMI98ij0Lr24wIVUr7ACh0XJAU9EAYYCCABEgLDyPD_BwE  Similar but not the same thing.


Title: Re: Steve's BIG BETSY Project
Post by ZYGI on 08/09/19 at 21:23:50

If you are using the circle cutting jig, you want your whole bit to be in the wood. Both sides of the cutter must be in the cut at all times. What that means is, you can not have the one side of the cutter exit the cut at the outermost part of the arc.

When you do it this way, you always cut in the direction so the piece you want, is on the climb cutting side of the bit.

If you wood is just wide enough for the baffle, your best bet would to take 1/8" deep cuts like Archie suggested and when you get half way through the depth of the board, you would jig saw off the waste as close as you dare to the finished baffle, then flip it over and climb cut the rest of the baffle, using a flush trim bit, while climb cutting.

Just my 2 cents...
Hope this helps!
Zygi

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/09/19 at 21:30:27

My wood is just wide enough so as I swing the arc, it will pass out of the wood when I reach dead center if that makes any sense.

So I like your suggestion of "flipping" but I don't have a flush trim bit.  My tool man (el presidente) left town and took his tools with him.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/09/19 at 21:41:38

ZYGI, why is that? Is it just for spiral bits?  I'm guessing it must be since the flush trim bit works with an open side.  What happens if the bit cuts on just one side?

I don't think there's enough meat for the "T" bolts, as I call them.  I think I had 1/4" to 5/16" for the screw.  I used #10 pan-head wood screws.  The head of the screw can't be too big either or it won't get passed the lip on the driver.  I didn't flush mount and I like that look.  Randy mentioned that he couldn't hear a difference between flush and recessed and recessing would have taken a better jig than I had.  You could always rear mount as Steve is doing with the Crystal-10s.  (But with screws.)

My vote for a finish would be a stain of your choice followed by wax or oil and then wax.  Super easy finish and what Steve did on his BBs.

Title: Re: Steve's BIG BETSY Project
Post by ZYGI on 08/09/19 at 22:38:59

ZYGI, why is that? Is it just for spiral bits?  I'm guessing it must be since the flush trim bit works with an open side.  What happens if the bit cuts on just one side?

Archie, if you are climb cutting and you are out of the material on the opposite side of the climb cut,  there is a possibility that it can gain traction, so to speak, and take off on you. Not only very dangerous unless you are used to it, but as it bits in it usually takes chunks out wit it.

All it takes, if you are using the circle cutting jig and its open sided is the jig flexes from the operator readjusting his position or his hands and the bit digs in,  you can not just pull the bit out away from the wood to stop it. It is sort of trapped, and goes.

My main reason for flipping and using a flush trim bit, is this...if you only cut half way through, the rest of the off cut is still intact,  there is no way you can take a huge chuck out like what happened to Steve on his baffles.  

If I were to make two baffles, (and I'm guessing for a stereo piar that would be the case) I would only cut the arc on one side of one baffle, the saw off the excess from the other edges, and flush trim to the first baffle, using it as your template.

Just my way of doing things. Nothing worse than having all your stock glued up and have a major disaster with tear out.

Donnie...Machinist mill, woodworkers cut....

Title: Re: Steve's BIG BETSY Project
Post by ZYGI on 08/09/19 at 22:41:54

Archie,

i don't think it really matters the type of cutter really. Up cut spiral or down cut. I use, with great results, a cutter that has both up, and down on the same cutter. Bearings on both top and bottom as well.

Zygi

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/09/19 at 23:01:53

I guess I haven't experienced this as I don't do much pattern cutting with a router.  I am familiar with the router taking off and moving away from the work if I go the wrong direction.  Free handing hinge mortises takes an iron grip for sure.  It must also be a function of how much you're taking off since flush trim bits work only one side, by definition.

Title: Re: Steve's BIG BETSY Project
Post by ZYGI on 08/09/19 at 23:22:24

It must also be a function of how much you're taking off since flush trim bits work only one side, by definition.

Not necessarily so....

I use a flush trim to bore all the driver holes whether they be round or square. I have the pattern down below, drill a 3/4" hole somewhere with in the circle to be cut and run straight until I find the edge of the pattern then cut the whole thing in one pass around.

The beauty of this, is I use it over a vacuum source table which sucks everything down through the slot the cutter makes.

The bit I use is this.
https://www.woodworkingshop.com/product.aspx?item=WUDC9112

But yes, for the most part, it's only a one sided bit.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 08/09/19 at 23:27:01

Zygi,
Mea Culpa. Lol!
This wood cutting stuff is new to me!
The physics of it are the same but the terminology sure is different.
The main thing is how the chip is formed and how the mechanical reactions are handled.
Like I said before, I could bore the living shit out of all of you talking about chip formation, chip loads, surface footage and much more esoteric things.
I sure do like listening to a true artist describe their art. My strength has always been the science of cutting materials, I've never had the talent of a artist.
"Perfection can never be attained, but it sure is fun chasing it".

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/09/19 at 23:59:47

That just shows my in the box thinking!

Title: Re: Steve's BIG BETSY Project
Post by slk23 on 08/10/19 at 00:03:38

I've had my F15s for a week and while they are excellent I think I'm going to focus on other projects.  If anyone is interested in buying a like-new pair of drivers send me a PM.


Title: Re: Steve's BIG BETSY Project
Post by ZDubzNC on 08/10/19 at 18:51:28

@slk23 - I might be interested in the pair. I'm a newbie poster here on the forum (been reading for a while), so I can't PM you since I haven't hit five posts. I'm not sure if you are able to PM me?

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/10/19 at 23:21:56

Welcome to the forum!  ... and the family!

Steve

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/11/19 at 01:49:16

It's starting to look a lot like Betsy...











I could have stained the deck or built a few baffles.

The radius cuts were not easy.  I made it without any chunks flying out.  My hats off to you guys that did those cuts with 1.5" wood.

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 08/11/19 at 02:09:09

Nice work Pal!  And how do they sound?

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 08/11/19 at 02:16:26

The Crystal-10's arrived today!  I am not sure what impressed me the most when I unboxed them, the drivers themselves or the wood boxes they came in!   :o










Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/11/19 at 03:11:22


Palomino - I can't believe you gave up staining the deck... what a putz. [smiley=rolleyes.gif]. I could have been building baffles today too but I did the right thing and installed a new tankless water heater.  You should of seen me towards the end of the day, on my 6th trip back to Menards for stuff when I discovered 3 feet of 3 inch vent pipe (a 90, a pair of 45's and a single 12 inch straight piece) cost another $270.  I did some street graffiti with the 72 Monte on the way home to make myself feel better... and it I wasn't so tired I'd be out there mounting the drivers in the new baffles right now.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/11/19 at 04:03:18

Pretty impressive looking drivers Jeff.  Can’t wait for your report.

I haven’t go the other side done.  Still need the supports attached. Once I finish I’ll give them a listen and let you know.

I’m interested in the tankless install Steve.  I have been thinking about doing that myself.  

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/11/19 at 17:29:04

Looks like I made the right call.  Wouldn't want to have the deck get rain less than 24 hours after staining it.  Also, now I can listen to the Big Betsy's today without guilt.




I'm in that state of wow so maybe you guys can help me sort out what I am hearing, feeling and measuring.




First of all, the big Betsy's are BIG.  They dominate my small 16X12 listening room.  They aren't really taller than other speakers I have had in here, but they are wider.

Does it matter?  Not when I close my eyes.  They completely disappear.

And the F15s sound completely different in the big baffles vs the low boys.  The hit Steve talks about is definitely there in spades.  And you feel the bass much more in your chest.  Like every song with any bass you feel it.  I am listening to a guitar song accompanied by string bass and feel it.

I'm thinking, this HAS to be digging deeper so after about an hour I break out the measurement mic and REW.  

Identical bass under 100HZ.  I think, how can this be?  So I look at 100-200Hz and the response has greatly flattened out.  No dip like I saw before.  A little louder in this section, but mostly it has flattened out the response.

The only other significant measurement difference is above 10K where the highs are definitely more extended.

But the speakers sound completely different.  I would definitely agree with Steve's comment about the whole baffle being a transducer.  You just feel the music more.  Its like a giant wave hitting you and your body buzzes.

So, I am using 1.1" stair treads glued together. I'd give myself a solid B on woodwork.  I decided to flush mount them and went a little deeper than I should have.  I ran one of the mounting screws out the back and I did find a a ding on the back side edge of one baffle where it got away from me.  All of these can be addressed.

Does this experiment suggest that a lighter wood version of the Big Betsy would give you 80-90% of the heavy wood version?  I like to think so.

I may not finish these and bring them to Decfest for comparison.  That way if they take a few knocks, I can sand them out.

So I am pretty impressed and feel the time and expense was worth it.

Thanks to Steve and Randy for the design and inspiration.  These sound (and feel) really good.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/11/19 at 18:15:19

Pal, What are your footers like?  Did you fully support the bottom of the baffle like steve or more like mine (according to your picture).  Did you mount them 90 degrees?  Any front feet?  Did you score those handles?

I wanted to mention that in one of your previous posts you said something about vibrating your kneecaps.  I thought you were just using flowery language but several times, my kneecaps were vibrating!   :D


Your description of the bass is very interesting and I  hope you get the chance to try them with a ZR2.  But if you do, your head might explode!   8-)

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/11/19 at 18:38:58

My footers are 11” long solid oak blocks that are around 3” by 2.5”. I repurposed some desk legs a friend in the office business gave me.

They just run 90 degrees out from the baffles secured by a lag screw.  I used a forester bit to drill the holes for the lag bolt.  I will cover these holes with a 3/4 wood plug I got at the hardwood store once I finish the baffles.  

I may also put some in front as Steve did.  I was going to and I screwed up one of the 4” blocks when I was cutting the table leg on the miter saw.

I may beef up the supports at some point.

I did score the handles for $12.  Supposed to get here Thursday.

Randy mentioned knee rattling quote.   I like the nice body buzz these drivers give.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/11/19 at 18:43:41

BTW I did find an online article that talked about most bass being between 90 and 200hz so what I am hearing/feeling is in that range.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/11/19 at 18:47:19

There are design points that it would be interesting to see what effect/difference they make so I hope you get to take these to Decfest.  I'll have the weights early next week to try.  I really like the look of your oak.  I keep toying with the idea of making prettier baffles down the road.

Well, my kneecaps were definitely rock'n!  (I wonder what their resonant frequency is?)


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/11/19 at 19:45:28


Palomino, your baffles look great!  Also encouraging is that 1.1" hardwood seems to be working!  

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/11/19 at 19:58:02




Installing the drivers and handles.

Steve


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/11/19 at 20:05:12







Title: Re: Steve's BIG BETSY Project
Post by ScottNC on 08/11/19 at 20:07:00

Steve,
Those are awesome. If aesthetics were the only thing that guided great sound, those would knock it out of the park. I can’t get over how that heavy wood just looks like it’s gotta be great.
Best,
Scott

Title: Re: Steve's BIG BETSY Project
Post by Lon on 08/11/19 at 20:12:13

I agree with Scott, both sets of recent baffles look beautiful.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/11/19 at 20:13:23




A nice backlit effect showing off how little the three spokes of the driver frame reflect the sound.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/11/19 at 20:26:55


A closer shot of the driver/baffle relationship, specifically how the radius extends from the surround. This should effect an ideal wave launch by cleaning up the standing rings of air the surround would otherwise make at the circumference of the cone. I almost did this on the Big Betsy, but since the F15 driver surround/gasket/frame relationship is not exotic, like the Crystal 10 driver, I radiuses the back side of the Big Betsy baffle instead.  



Steve


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/11/19 at 20:48:23




Now to get them breaking-in and do some casual listening! If they don't make me smile in the first 5 minutes the design will have been a failure and my fears about thin sound will be realized. Thankfully I choose to dwell on the likelihood that just the opposite will happen proving the Audio Gods know a lot more about it than I do.

After all, coming from the Big Betsy -- some of you already know how high that sets the bar -- these are going to have to be really good just to survive.

Steve



Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/11/19 at 20:51:57

Incredible baffles Steve. Just beautiful.  Can’t wait for your review of the Crystals.

Well the big Betsy’s just kicked my ass for the last couple of hours. Talk about they are here.  Eric Clapton was just in the room.  At some point I will put the OBs I have been working on for the last couple of years back in.  It will likely be quite humbling.

I predict Steve’s big Betsy’s will hold court at the fest the way the 25th did last year.  You have to figure out a way to offer these commercially.  

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/11/19 at 21:01:54


Agreed. I knew that the first time I heard them. And this is the process. I already know if these Crystal 10 baffles sound good they will be a popular alternate for people. I was able to lift them without issues, they fit through even smaller doorways and would not dominate a room as much. These came out a lot smaller than I was originally hoping for, but as mentioned in earlier posts the difference in size probably wouldn't have been enough to make it worth having two baffles so similarly sized.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/11/19 at 21:03:15

I gotta say, that figured oak is stunning!

Pal, it sounds like you're getting the BB experience.  I've never had amazing sound staging at my place but these sure do "blow up" the music.  It's almost like looking at an exploded parts diagram.  A new experience for me.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/11/19 at 21:04:21

Steve, you can always make a fixture and try them in the big baffles.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/11/19 at 21:13:24

Well if the crystals even get or exceed, that’s the ticket. This is what open baffle is supposed to be.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/11/19 at 21:42:02


Well, Good News! The Audio Gods were right and I was wrong. After about an hour of warming up with stringed instruments only, I went into the room to listen.

A song called Nexus by Daniel Voth was playing. It started out warm and big as the result of a loud chorus recorded perhaps inside a church and done at a level that easily saturated the recording space, a sound that you would normally blame on speaker cone breakup or box resonance. The sound was almost thick and dull as a result but then transitions into some solo guitar work with graduating layers of dynamics each slightly louder than the previous one and the contrasting clarity was a nice trick to really get your attention. At around the 3 minute mark my head exploded! I had to pause it and walk around in circles for awhile which is what happens to me when I hear something happen that I've never heard before.

I've never heard anything this good so soon in the game and there is a very obvious difference between the sound of these and virtually every other driver I've heard to date, which would account for these pre-burned-in results. This on drivers only an hour or two out of the box.  I'll talk about this more as we get into it.

Hehe, no worries about the bass with these speakers, everything is well balanced already.  

So far I have sat in the sweet spot and listened for exactly 3 minutes.  I'll pop in there several more times throughout the evening, perhaps better armed with some Depends.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/11/19 at 21:53:12

Steve, you originally thought you'd be using the ZROCK2 with these.  What is your initial setup?  I think I read that these take a long time to break in.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/11/19 at 21:59:50

I looked up that piece of music and hell, it sounds good on my crappy computer speakers.  I can see why it stunned you.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/11/19 at 22:09:51

My kids gave me depends as a gag gift for my birthday.  I may just bring them to the fest with all this new stuff happening.

Title: Re: Steve's BIG BETSY Project
Post by JOMAN on 08/11/19 at 23:59:20

I’ve been following this thread with interest and I had a good gut feeling about the Crystal 10.  The large baffle is too big for my space and I felt that a smaller version with the Crystal 10 might do the trick.

This may be way out there but I have to ask...

What about two Crystal 10’s in each baffle, one rolled off with an inductor similar to the design of the S3HOXRS?  Even if the baffle is slightly taller but no wider than the Walnut/Oak baffle.

Yes the cost would increase but would the results justify the added costs?

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/12/19 at 00:31:25


With regards to the ZROCK2, I have installed one permanently on my digital source.  It's between by DAC and the ZTPRE so I can run it or bypass it at any time. What I've noticed with the Big Betsy and virtually all of the Decware and related speakers is that none of them need a ZROCK2 to sound good in our room.  All have the correct amount of bass which is to say that none of them sound thin.

For this reason the bypass switch is invaluable, because with the unit bypassed if I can't get good sound from the system, there is something up with the system, a red flag.  That said, I find the ZROCK2 just makes the midrange sound so much more pleasing that I wouldn't really care if it didn't do anything for the bass, but it does and music just sounds more real with it in unless it was recorded with a similar curve already.

The new Crystal 10 baffles will not require a ZROCK2 as originally anticipated. That said, I will be using one anyway most of the time with my DAC.  On my vinyl rig, or tape machines I never use it, so doubtful I'll start.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/12/19 at 00:46:28

Ah yes, the ZR2 and the mid range.  For me, one of the two curves really sweetens that up.  Switch down.  I think the opposite curve than I would have thought.  I've always wondered if it was wired reversed.

I'm really looking forward to the F15/CR-10 shootout.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/12/19 at 01:18:55




FIRST IMPRESSIONS

Before eating dinner tonight I got to spend another hour with the speakers and am pleased to report the following:

A) They seem to get exactly as loud as the Big Betsy F15 combo.

B) They sound full and rich, with enough bass to be enjoyed without augmentation.

C) They have the same energy that you feel when you listen to the Big Betsy, similar slam and scale.  I would say less slam but same scale.

D) They give enough of the Big Betsy / Capitan Crunch sensation that you know you still had a Big Betsy experience... I wasn't expecting that.

E) The sound is refined beyond description. The top end and midrange, well, let's just say that it's in a league all its own. I would say that the sound of this driver is so good that it would be sacrilegious to speak of the music it makes in segregated terms like 'bass' or 'midrange' etc.

F) It was designed by a true genius with a deep understanding. It possesses a cone that you can not hear.  

Sound always takes on the signature of the last surface it touches, so the sound of a speaker cone is always superimposed over the top of the music.  Not here. I've listened to so many drivers and cones when I had a speaker re-cone business pre-dating DECWARE, and then all the stuff that came along after DECWARE, like the Fostex, Lowther, and similar drivers that use thin smooth paper cones. You can hear those cones, and now that my reference has been calibrated by less than a couple hours with this driver, well lets just say I'm wrecked about as bad as I was when I came out with the 25th Anniversary Zen Triode amplifier.  Anyway, to finish the thought, this is the first and only driver that I can not hear the cone. It's simply brilliant.

As a result the sound comes out of an empty space full of all possibilities. For example in the first 3 minutes of the Daniel Voth track I spoke of earlier this afternoon, I was thinking OK, this cone material is refusing to break up, and it's so soft and smooth sounding, if not a little dull. This was because I could not hear the cone which would have otherwise added an artificial edge that would actually be interpreted as an increase in focus.  Then all of a sudden some dynamic attacking high notes exploded into space right in front of me that I had a hard time registering as having just come from the same speakers!! The absence of cone sound makes the music smooth until something dynamic happens and then you wonder how such attack and high frequency is possible without compression or distortion.

Sorry I had to explain F).

They do not have the giant bass hit of the Big Betsy, but what they do have probably is Truer to the actual sound with less hype in the mid-bass region. We will see what happens over time as these season and my brain continues to wrap itself around what I'm hearing... right now I would say that if you listen to both the Big Betsy and this smaller model with the Crystal 10 you will literally HAVE to have both. Consider yourself sufficiently warned, because if you think you don't have room the Big Betsys... imagine how upset you'll be when you find yourself with both.  This years fest is going to be a disaster for everyone who attends ; )

-Steve  

Title: Re: Steve's BIG BETSY Project
Post by Lon on 08/12/19 at 01:31:21

Great news! Another exciting moment in Decware history.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/12/19 at 01:34:59

IDK, this is starting to sound like polygamy.  But what if we HAVE to choose?   :'(

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/12/19 at 01:52:27



Quote:
Steve, you can always make a fixture and try them in the big baffles.


We are making the assumption the sound will improve with the added bass, but despite that it might not. I thought "IF, I could only have one pair", I would probably do just that, but now I realize it could be a trick. I would need to hear the two side by side or in back to back sessions and see what jumps out as the trade-offs in both configurations because it's possible that for whatever reason I might like the sound better from the smaller baffles do to the proportioning accuracy with the main driver.  

And the reality is that the F15 loaded Big Betsy has the hit that nothing else, not even other 15 inch drivers can match. It's that hit and even keeled midrange that I love about it. It makes classic rock sound like we all remember it, so again, I would loose that even if the Crystal 10 was in a bigger baffle.  That's what I mean, you will have to have both.  Personally, I would take all the other speakers out of the room before I choose between one or the other of these insane baffles!

One thing I did actually do as an experiment with the Caintuck Audio Betsy Alnico baffles was to use the F15 in the Big Betsy as bass augmentation crossed over at 90Hz driven in parallel by the same amplifier. It worked really well (really well). So a similar thing could be done with these if you were so motivated.


Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/12/19 at 02:17:17


Right now I am listening to Sweet Pain by Nusrat Fateh Ali Khan & Michael Brook and the bass could be mistaken for the Big Betsy bass.  Amazing!  Fun to see the speakers slowly release their secret sound as they loosen up and develop more bass.  At this level I am MORE than impressed and pleased.  I'll be damn, it's just hard to believe.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/12/19 at 02:47:54


OK, someone's messing with me.  Listening to Luca Stricagnoli - Snow (Hey Oh) and the bass is ... crap it sounds like the Big Betsy's are hooked up.  I am catching myself looking in there as if somehow one of these glances the Big Betsys will be hooked up explaining what I hear and then somehow rationalizing the memory loss of having switched the speakers, but no, they just set there like in the picture.  Holy hell, these things really do hit.  Now I feel embarrassed for doubting the baffle size.  It sounds just like the Big Betsys in the bass but with a words can't describe it sounding everything else.  

I don't know how it's doing it, but this is just over the top.  Rainfall - Adrian Bellue. Where is all this weight coming from?  Ahh ha, it was the ZROCK2.  A nice performance without it, but much drier sounding.  Man, the resolution of these speakers is magnifying the effect of the ZROCK2 midrange healing powers a lot!  But also the bass is just insanely good and serious.

Imaging is fantastic.  A beautiful large sound stage being painted by Luna - Sergio Altamura as the sound finds the boundaries of the recording space.  The room sounds as beautiful as the guitar.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/12/19 at 14:01:17

Well, day 2 of listening to Steve/Randy’s triple Bs.  I’m still trying to wrap my head around what I am hearing/feeling.  I listened to that guitar music playlist I posted above (added Steve’s track – thank you).  I only had 35 minutes but it took all of about 5 for me to get in the zone.

My kid played in a battle of the bands last night.  Bad room/bad sound, but what I came away with was how the sound resonated in my chest.  I measured the sound levels and they were consistently over 94db.  I am getting a less intense version of that feeling with these baffles and I am in the 80db range.

What’s also weird is that the music is clearly within the sound stage, but I can feel the resonance from all over the room.  That leads me back to the comment Steve made about the panel being a transducer.  So I guess my conclusion is that you want a stiff baffle, but definitely not deadened.  Maybe if there is an offensive frequency or something, but overall, I think you want to ride the wave.

Which then lead me to thinking about baffle thickness.  Maybe there is an optimal thickness for this transducer?  Randy uses ¾”.  Is that due to practicality of shipping, wood availability?

All I have is my experience with the PAP OB project.  ¾” Baltic seemed too thin to me and possibly too high pitched, 1.5” MDF seemed too thick and sluggish.  I don’t recall getting this sensation with 1.5” Baltic.  So I am thinking its hardwood, but the right thickness is yet to be determined.

Random thoughts but this speaker challenges you to think differently about sound reproduction.

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 08/12/19 at 15:19:47




Quote:
Which then lead me to thinking about baffle thickness.  Maybe there is an optimal thickness for this transducer?  Randy uses ¾”.  Is that due to practicality of shipping, wood availability?


Hi Pal,

Yes to all of the above .....

While I am a big fan of my low profile baffles for a variety of reasons, the availability of 3/4" stock is a primary reason.
It also holds down shipping and build costs for speakers that are intended to be affordable for most music lovers.

I know for a fact that "everything" makes a difference in speaker construction ..... and thicker baffles certainly have an effect on the sound, but my guess is that it makes a much larger difference in baffles that are larger than the ones I am building.

It will be very, very interesting to compare the sound of the various baffles that will be available at Decware Fest 2019 .....

Best wishes,
Randy


Title: Re: Steve's BIG BETSY Project
Post by ScottNC on 08/12/19 at 15:33:52

It sure is looking like there will be some great “Takeaways” from DECFEST this year, particularly if a few builders show up with baffles they have made. Can’t wait to see what results from all this,  very exciting stuff I think.
Scott

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/12/19 at 15:36:23

That could be very cool.  

I'll take my direction from Steve.  I have brought speakers/equipment in the past and its lead to a bit of a cluster.  

I will definitely be able to say that BBBs or MBB provide the effect I am describing.

Title: Re: Steve's BIG BETSY Project
Post by slk23 on 08/12/19 at 15:39:30

@ZDubzNC

Could you please email me? StephenLKearney at gmail.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/12/19 at 16:31:47

Pal,  I'm leaning in the same direction as you... I think it's hardwood that makes it happen the most, and I believe the thickness should be determined by the height and width of the baffle. The Big Betsy Baffles are 1-3/4 while the Crystal 10 baffle is 1-1/2. My gut feeling is that had I made the smaller Crystal 10 baffle 1-3/4 it would not work as well.

I suspect that you will know after you listen to my Big Betsy if there is a difference worth chasing. Problem is you won't know if it's the difference in thickness, or the high mass bass the baffle is secured to, (or both).  But the main thing is you will know if they sound a lot different or not and that is the first step. If they sound basically the same then we'll know it must be pretty forgiving.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/12/19 at 17:11:20

When I first brought the wood home I thought this stuff is going to ring like a bell.  Then I felt the baffles when I was first listening and thought, well, maybe not.  I have a stethoscope and a sweep pattern, but I don't think I have control over how fast or slow that sweep plays.  I'll have to look into it.

Another thing I meant to mention as far a a build tip is concerned...start with new, good quality, router bits if you can.  This hardwood completely dulled two separate bits.  Granted they were off the shelf Ryobi, but the oak destroyed them.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/12/19 at 17:13:53

I'm almost on pins and needles over the F15 vs CR10 comparison.  If one is the clear "winner" than I might be looking at another baffle build to fine tune or change over.  Some of my early questions are regarding the use of the ZROCK2.  How they both compare with and without.  And how the CR10 does with a different amp.  I'm assuming, Steve, that you are using the Zen-25 right now for the CR10.  I wonder how they will do with more power and whether other amps can control the bass.

My brass weights are due today so I'll see what an additional 14 lbs per baffle, strategically place on the back, does to the sound.  I already know what the weight will do to my ability to lift these beasts!

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/12/19 at 17:17:57

Archie, do you feel this wave of energy that we are talking about?  

I swear I have never felt this before with any other speaker.  Maybe its like an electrostatic speaker, but I don't remember those speakers well.  Its been a few years.  Those should theoretically provide a wave of energy.

Maybe its because I am in such close proximity to the baffles?

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/12/19 at 17:49:11

I can't say yes or no.  These are a very different sensation than my other speakers, including the radial HR1s.  My experience isn't so much physical as mental/aural.  I "see" the music laid out in front of me almost like each piece has a vertical and horizontal position.  I can go more into the music like the tesseract in the movie Interstellar.  This might be your normal given your treated room but for me, the last time I heard it like this was in the early 80s and I had some help form an "outside influence."   ;)

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/13/19 at 01:32:44

I installed the brass weights using the 3/5, 2/5 rule.  They are a bit less than 3 1/4 lb each, so a total of 13 lbs per baffle.  I've spent the last couple of hours listening to music I've listened to already with the "stock" baffles and while subtle, I think I'm getting more focussed sound and better "hit."  I don't know the real definition of "hit" but I'm calling the relative decay of sound a measure of "hit."  The impacts of a drum that should decay almost immediately now seem to hit me like a sharp blow.  In fact, I can feel the impact.  I haven't done much with a stethoscope but there seems to be much less vibration in the baffle.  I think this would be consistent with what I've already written.  Keep in mind, I spent about $155 and my time on these weights so I could also be in placebo land.  Certainly, the sound has not degraded in anyway and I did not identify any real weakness before.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/13/19 at 01:34:00

Closeup of a typical weight.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/13/19 at 01:36:04

Blanks of brass before drilling and countersinking.  I prepped them by taking the hard edges off and lightly sanding on emery cloth and a little buffing with coarse steel wool.

Title: Re: Steve's BIG BETSY Project
Post by BAndrade on 08/13/19 at 01:49:20

Folks, anybody installed Big Betsy's these on speaker spikes? The reason I am asking is because the large front face presented by these OB speakers would be prone to cause the speaker structure as a whole to vibrate and move (micro movements) and spikes might help in anchoring the speaker preventing lateral and transvers micro movements. My feeling is better anchoring will help in making bass tight and improve punch.

Additionally I think that adding brass weights to the back of the these thick rigid baffles is not going to help damp resonances as in the case of the flexible diaphragm test in the video in a post before (the one with sugar sprinkled on a vibrating surface at different frequencies). In that case the diaphragms were chosen because they gave the right amount of flexibility which was needed at the large diaphragm was the main source of sound production. the down side of this flexibility was there were multiple resonant frequency introduced that needed to be damped by strategic weight placement. In the rigid Betsy baffles the sound's origin is mainly the driver directly and less from direct reflections from the baffles surface and the primary purpose of the baffle is in isolating the front sound waves from those emanating from the back (due to the lack of an enclosure). In fact mental modeling suggest that in a rigid baffle the brass weights might if place high up might cause a upside down pendulum effect exacerbating the vibrations .

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/13/19 at 02:19:12

Good questions and hard to answer.  In my case, I'm not about to spike my 75 lb+ speakers to my finished wood floor for aesthetic reasons.  Also, my observation, in my place, is that when speakers couple to the floor, I get bloated, muddled bass since my floor is "untuned," if tuning is even possible.  I took exactly the opposite approach and isolated them.  I'm not 100% sure this improved things but it didn't seem to hurt either.  I'm going with the theory that the high inertia will hinder micro-movement -- short of some resonance overcoming the inertia.

As far as the weights' effect, my idea isn't that they damp resonance (they are strongly coupled to the baffles) but rather they breakup resonance by scrambling the apparent stiffness of the baffle (hence the 2/5, 3/5 and 20% to 25% of baffle mass).  With my investigation using test tones and a stethoscope, while far from comprehensive, I did find spots of higher frequency response.  My hope is that the "semi random" variations in stiffness caused by the weights will break these up.

These baffles are too complex and cumbersome for me to do much detailed experimentation but I'm pretty sure that if I haven't made things better, I also haven't made things worse.  More time might tell.

Title: Re: Steve's BIG BETSY Project
Post by BAndrade on 08/13/19 at 02:44:44

I get it, also important folks in one's household might not appreciate dibs in the hardwood flooring.

I was only pointing out the sonic benefits leaving everything else because even enclosed speakers with much less of a front surface area and weighing more with 5 to 6 drivers and thick all round enclosure have spikes for this reason.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/13/19 at 03:02:04

Mine are just sitting on carpet over cement floor (basement).  At
this point I’ll add the handles and listen for a while before I decide if I’ll do anything else to them.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/13/19 at 03:11:19


I have some beautiful spikes for the Big Betsy Baffles I built, but will wait until after this years DECFEST2019 to try them out. They have balls on the tips instead of sharp points that I am certain will do a better job on my floor. I am on a concrete floor with padded carpet and personally I like as much energy in the floor as possible so long as it is congruent with the source.

I don't know what to expect from spiking it because the mass of these things is so great and the focus seems quite good. There will absolutely be a significant change in sound I predict because instead of energy being stored in the bass and becoming scalar against incoming energy, the spikes will drain the energy into the concrete and earth under that. I will be stunned if I don't hear a difference, but I have no idea at this point which will actually sound better. Don't worry I'll let you know this fall when it happens.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/13/19 at 03:22:49


Archie, I love the brass weights and the placement even randomly would help to de-tune (widen the Q) of the baffle giving it a more relaxed sound with improved clarity.  At least that's the logical conclusion.  Should have stopped with one and then A/B the two speakers against each other to hear if there is an effect on music, but having a frequency generator app on a smart phone or tablet could also easily reveal any differences.

Steve

Title: Re: Steve's BIG BETSY Project
Post by will on 08/13/19 at 03:35:28

Sorry folks....slow typer...and found several responses as I posted...anyway...

Archie,

I guess it all depends on a lot of things, and it sounds like the wild card of the baffles being an aspect of the transducer presents interesting challenges... shape, mass, thickness, weight...all being players makes sense.

Here, with my brick on sand floors and HR-1s, I tried heavy spikes, and smaller spikes, direct on the floor, and on those little spike protectors, and these were my least favorite feet. They were better than none, but relatively speaking sort of crude and rigid sounding. Then I tired Herbie's gliders and found them to be too damping for my tastes, but better at nuance and fine detail. With a few modifications those got pretty good though...more complete, more nuanced.

Finally I got tired of the "sound" from over-damping (to me), and got some ingress audio threaded, spun aluminum feet with highly polished seats and bearings. I added some relatively rigid sound damping material under them (sound coat) and the sound is quite neutral to me, more articulate, improved bass articulation, more refined and complex timbre, and quite nuanced while not sensing veils. Pretty "right" to me. Limited experience and conditions, but I don't think about changing feet anymore.

I believed you when you said this: "I spent part of the day building isolation platforms for my Big Betsys.  I had do do a "template" base first to fine tune the position of the springs so the things would sit without a tilt.  I'm going to say that isolation was a big success.  Bass is tighter and much less distorted at high volume."

This fits my experience with your springed platform under my CSP3...with a little extra damping feet added, it seems quite balanced and effective to me...I suppose as much as any component foot I have tried. I seem to recall it was close to my favorite of that time, Madscientists best feet (then) under my Torii.

All in all, I seem to be in agreement with you, that I like isolation better than direct coupling, and like a little damping with it, but not much.

I look forward to hearing more on these great baffle experiments and solutions. I seem to be closing in on what may be a good design for a 10" driver, using ideas from this thread and playing with adjustments to better fit my space and room aesthetic.

Thanks to all for this cool thread.

Will

Title: Re: Steve's BIG BETSY Project
Post by BAndrade on 08/13/19 at 03:38:27

Just feel those 15 inch drivers and long throw drivers on the BB's would move a bit of air and that perhaps spikes would help the cause. A wee bit air pressure translates into quite a large force when that pressure acts on a large surface area.

Picture of spike pokes on my hardwood. Originally the spikes were on special tips that came with the speakers that protect the hardwood, until one fine day I decided to try the speakers without them. Bad idea, could not go back to the protection tips since I found bass was more impactful and clean. See not suggesting anything I would not do and have experienced myself.  

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/13/19 at 04:22:54


With regard to the differences between the two and how the ZROCK2 plays into it...

The Crystal 10 in the smaller baffle with a ZROCK2 sounds similar to the Big Betsy without a ZROCK2, as predicted by the difference in baffle size and QTS differences in the drivers.

Also the Big Betsy has more weight and hit at lower volumes than the smaller baffle with the Crystal 10 which is to say that low volume listening is better served by the Big Betsy / F15 combo. Naturally if we were running the Crystal 10 in a cabinet instead of an open baffle this would not be the case, it is just the side effect of using a driver with a lower QTS than would be ideal for open baffle use.

Interestingly the tape machines and vinyl rig which are not ZROCKED have a similar density and weight as though they were.

So we're into night two with these speakers and I have my guard up this time and feeling extra critical and picky... what I'm finding is that the gap between good and mediocre recordings is doubled. The good recordings are simply fantastic if not euphoric. They take you where no-one has gone before and like your favorite amusement park ride when you were a kid, you don't want it to stop.

The biggest thrill is that like I had hoped, they have the ability to accelerate and extend high frequency presence like the 8 inch Betsy Alnico drivers used in Randy of Caintuck Audios baffles, but have the efficiency of the Big Betsy and about 72% of the slam which is enough to make someone equally impressed with a 25th Anniversary Zen Triode amplifier on either speaker.  What the Crystal 10 doesn't have in low end slam in these baffles it makes up for in uncanny 8G acceleration into each dynamic that can make close miked acoustic guitar music literally levitate you above your chair.

It has the same Big Betsy energy once you turn it up that has been described here in recent weeks, if not more of it which really lends a tactful experience usually reserved for live music. This kind of energy is easily dulled by unnecessary complexity of which there is none in this set up so everything lights up pretty good including your own body.  

It's just such a game changer to have a crossover-less speaker that's 100dB with body and weight to let our 2 watt Zen Triode Amplifiers actually outperform our larger push pull somewhat legendary amplifiers.  I mean with these speakers the need for a larger amplifier to give you the ability to turn it up louder is eliminated. These speakers paired with our 2 watt Zen Triodes outperform our 94dB DNA2 speakers paired with a TORII MK4 / 25 watt amplifier. It's just such a thrill to get to this level with the 2 watt amps because as we have always known, they actually hit harder than the push pull.

Welcome to the upside-down world of Decware where everything seems backwards when you come from the main stream audio market. And the best part is that it doesn't seem backwards and then in the end prove to have been a bunch of bullshit, instead it seems backwards because it's actually forwards and everything else is backwards. Yes, it's a narrow tunnel leading away from the masses but once you get infected with our passion and insights you'll be empowered to achieve the sound you've always dreamed of in a way that you can financially justify and still afford to feed a friend.

Steve










Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/13/19 at 05:19:28


Presently listening to 'Skylark' by Jacintha - Autumn Leaves(The Songs of Johnny Mercer) on the Crystal 10 Big Baffles and really think this is a new reference. I've never heard it sound better than this on any of our other speakers and I always forget it's only a two watt amp. It sounds like 200 watts.

... the naturalness of this combination is just so believable that in a decent listening room it will sound completely real on these speakers.  Interestingly it will sound completely real on a number of lesser speakers also. The trick is your perspective or reference. I thought the same thing about my favorite DNA2 speakers which I love, but these sound twice as real, so there you go. I always considered the DNA2's an industry slayer.  Something that would embarrass most hi-fi speakers in the 2500-7500.00 retail range without challenge, and higher in most cases for a number of reasons yet 6dB of honest gain across the range is 4 times the power, there is just no contest when you can hold it together at that level of efficiency.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/13/19 at 05:46:00



Quote:
While I am a big fan of my low profile baffles for a variety of reasons, the availability of 3/4" stock is a primary reason.
It also holds down shipping and build costs for speakers that are intended to be affordable for most music lovers.

I know for a fact that "everything" makes a difference in speaker construction ..... and thicker baffles certainly have an effect on the sound, but my guess is that it makes a much larger difference in baffles that are larger than the ones I am building.

It will be very, very interesting to compare the sound of the various baffles that will be available at Decware Fest 2019 .....  

Best wishes,
Randy


Randy, when I scaled your design up to create the Big Betsy, I though the super thick giant mass of hardwood would be like a concrete wall, nearly inert. What I found is that when I wrapped my knuckles on it in the same places as yours, it sounded exactly the same, as though the pitch was nearly matched.  Not higher, not lower.  That suggests to me that if you made your present size baffle double thick it may well not sound as good.  You had to know that the Audio Gods would at some point get bored with me and eventually find similar soles with the same vibration to whisper things to!  It's kind of a trip that they whispered through me to you, and then through you back to me again and here were are enjoying some amazing results.  While I'm sure that everyone at the fest will be impressed with the Big Betsy, I wouldn't get off of one for anything less than 7 grand plus frieght, and that's just a low estimate.  Similar with the Crystal 10 baffles.  Everyone will be stunned, especially those new to good OB designs.  But for probably most attendees it will be the trill of putting in your small 8 inch baffles that as far as I know range around $500~$1000 and after hearing the Big Betsy and thinking nothing has an open sound that images like that and then finding out the sound quality is equally good, equally big, the main difference being how loud they play.  It would be mean to let everyone hear the Big Betsy speakers without being able to take a piece of it home for less than the price of most cables!

Steve

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/13/19 at 14:07:13

I always have big plans for Decfest but usually I end up spending a lot of time just sitting on the couch like a blob swilling beer or off talking to someone. But this year I really want to learn about a few things.

Given that I will not always have a dedicated listening room, I’m interested in seeing what alternatives to the big Betsy’s there are.  Can you capture a significant portion of what I am getting now in a smaller package?

Sidebar: My wife comes down to the listening room on Sunday, sees the BBBs and starts snapping pictures.  I say “what the hell are you doing?”  She starts laughing and says, “my brothers and sisters have GOT to see this!”  Nice.

So, in no particular order:

1.      Betsy Alnico in Randy’s baffles
2.      F15 in Randy’s baffles
3.      ZR2 impact on the BBB/F15 sound
4.      Crystal 10…more detail?  Better sound?  Is there enough bass?
5.      Steve’s BBBs – is more wood/weight the ticket?

There will probably be a few others that I will think of.

My room is smaller, but yesterday I decided to crank the BBBs up.  I got it to peaks of 96db and thought maybe, I was seeing the VR tubes flicker al little.  I couldn't really hear any breakup so I got up and looked at the meters.  Barely dancing.

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 08/13/19 at 15:18:52



Steve wrote .....


Quote:
While I'm sure that everyone at the fest will be impressed with the Big Betsy, I wouldn't get off of one for anything less than 7 grand plus frieght, and that's just a low estimate.  Similar with the Crystal 10 baffles.


Hi Steve,

I'm still hoping that you offer these as part of your lineup .....

While I am very comfortable with the segment of the market that has worked for me since 2015, I know that there is a market out there that has deep pockets and is willing to dig into those pockets to satisfy their "audio sweet tooth".

On a pretty regular basis, I get emails requests to make larger open baffle speakers and I would much prefer recommending the BIG BETSY baffles rather than sending them the link to the Pure Audio Project website .....

I also find it interesting that the Betsy baffles are listed in the 2016 Stereo Times "Most Wanted Components" list ..... and there is a pair of speakers in that list that retails for $ 225,000.00 - 250,000.00 ..... so the BIG BETSY baffles would actually be a bargain.

The link can be seen here.

I'm on the same page with Palomino and am very much looking forward to checking out all of my speaker versions with a ZR2 at the Decware Fest in October.

Best wishes,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/13/19 at 15:20:44

Randy, will you be bringing a Betsy F15 set of speakers?

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 08/13/19 at 15:27:36



Hi Pal,

Yes I will ..... Steve already has a pair of original Betsy baffles and a pair of alnico baffles on site, so the Lii 15 baffles are the only thing I will need to bring.

Looking forward to seeing you,
Randy


Title: Re: Steve's BIG BETSY Project
Post by ScottNC on 08/13/19 at 15:58:18


Re: Steve's BIG BETSY Project
Reply #494 - Today at 10:18am  

Steve wrote .....

Quote:
While I'm sure that everyone at the fest will be impressed with the Big Betsy, I wouldn't get off of one for anything less than 7 grand plus frieght, and that's just a low estimate.  Similar with the Crystal 10 baffles.

Hi Steve,
I'm still hoping that you offer these as part of your lineup .....  

Yep👍🏼, I don’t have those deep pockets, but I agree.
Scott

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/13/19 at 16:55:13


Quote:
Archie, I love the brass weights and the placement even randomly would help to de-tune (widen the Q) of the baffle giving it a more relaxed sound with improved clarity.  At least that's the logical conclusion.  Should have stopped with one and then A/B the two speakers against each other to hear if there is an effect on music, but having a frequency generator app on a smartphone or tablet could also easily reveal any differences.

Steve



When I said in an earlier post that my test facility was primitive, I wasn't exaggerating, I don't even own a smart phone!

The weights come off with a single screw and I did pull them briefly to double check something and for me, their effect is subtle.  I highly doubt I'd hear a difference with just a single weight.  I tried weights on just one baffle and I couldn't hear a difference between them but a "stereo" test really wasn't a good test.  I'm too impatient for systematic testing anyway.  I'll just go along listening to music and sort of notice changes.  The weights do look cool though and like I knew what I was doing.   ;D

I know we've discussed the question of speaker isolation in other parts of this Forum and the question always gets mixed answers depending on individual experience with our rooms, speakers, floor construction, etc.  As is apparent from some of the pictures I posted, I have a LIVING room for a listening room.  That giant wood stove between my speakers is kind of important in the winter but I'm sure it isn't great for my sound (although I don't "hear" it).

Steve mentioned how the CR-10s widen the gap between well recorded music and so so music and the F15s show this as well.  Every once in a while I wonder what's happened to the magic and think that I've imagined how good the BBs sound.  I think it's also that we get used to the new higher level very quickly.  I've never spent so much time just sitting listening.  It's so enjoyable compared to what I had before -- which arguably, was very good.

Even if $7K + freight is really what these would sell for, the price is justified by the music that they make.


Will, I'm glad that you like that platform.  With a bit of refining, they do what they are designed to do.  But the "sound" result isn't guaranteed.   :)

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/13/19 at 17:07:14

Oh, regarding my experience with the ZR2 and BBs, when I do bypass (and give myself a minute to adjust) the resulting sound is very pleasant and one I could easily live with if I had nothing else to compare to -- Steve's "ignorance is bliss" thing.  But the ZR2 fills in all of the "empty places" and puts more meat on the bones, so to speak.  For me an analogy of the bypassed sound would be a gorgeous woman but one who's too skinny.   ;)

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 08/13/19 at 17:16:00

I only have one thing to say:
Chrystal 10's in a DNA 3.
TA DA!

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/13/19 at 17:41:55

As big as the Big Betsy's are, I would think that one of the most important things you could do to improve the sound would be to cover the back with felt to reduce reflection, as recommended by Darrel Hawthorne of Hawthorne Audio. And also damping the driver basket. The following is a quote from a 2009 article:

Many advanced builders are looking at these surfaces and asking the logical question. "How can we damp these surfaces and also keep them from being so reflective?" The answers coming back to us from our builders is that yes improvement can be realized if the driver is fully damped and several products have been suggested. The basic idea here is to add "soft mass" Soft Mass is something that lowers the resonant frequency through mass loading and yet stays soft and flexible. Modeling clays, duct seals, rope caulk and automotive damping sheet goods head up this list of products that damp well, and are readily available, inexpensive and removable. Many builders are also covering surfaces such as these with felt in an attempt at eliminating reflective surfaces. We like to cover the back side of our baffles with felt to help eliminate the possibility of these surfaces being the sources for these secondary reflections.

And also to adding additional mass to the base:

One way of adding mass that also does essentially eliminate vibration is the use of sand or metal shot. While strictly speaking sand cannot eliminate the energy content of vibration it can convert this to another form of energy called heat. That's right. Each little grain of sand/metal bouncing into it's neighbor converts these vibrations into thermal energy via friction and exchange. Some savvy builders are using sand to damp their baffles and especially the base or plinth that the speakers rest on.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/13/19 at 17:54:44


Randy, I am comfortable marketing these two hardwood Big Betsy speakers, but what we all know would be the hot seller is a pair of MDF or possibly Plywood versions painted black to get the price down drastically so more people could enjoy these two combos.  

I don't know what that figure would actually be but am hoping after some discussions between you, myself and Bob at this years fest that we can work it all out.

Steve

Title: Re: Steve's BIG BETSY Project
Post by lazb on 08/13/19 at 18:45:13

Yeah, Donnie, I had already posted that inquiry but got NO comments.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/13/19 at 18:54:17

It looks like about 4" down, but how far from the top of the baffle are you guys mounting your "handles."  I should receive mine this week and will be putting them on.

Also, I have some rope calk and what I call sticky tack (blue tack?) that I was going to try on the basket.  I like sticky tack a lot better.  I think it was originally made to hang posters on the wall.  Easier to work with and if memory serves, less residue upon removal.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/13/19 at 20:58:36

Pal, I went by eye and couldn't decide between 2 1/2" or 3" to center so I went 2 3/4".  3" might have looked better but with the weights I don't mind the room.  These aren't practical as handles but as a stiffener I would think closer to the top might make more sense?

When tapping on the baffle with my knuckle from the front, I can really hear where the weights are.  They must be doing something.  But as BAndrade pointed out, the baffles don't work like a panel speaker.

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/13/19 at 22:14:03

Well, I was so intrigued by all of the builds and impressions of the Lii speakers, that I just had to come up with a way to join in the fun.

I have no workshop, only a bare minimum of woodworking tools ( a handsaw and a cheap jigsaw ::) ) and almost no woodworking experience, so I had to go another route.

Jeff posted about having rings made so that he could modify his 15" baffles to accept the Crystal 10. He posted the name of the company making the rings for him, craftcuts.com , so I took a look at the site. The wheels then started turning in my head. (Thanks, Jeff!)

I wanted a baffle for the Crystal 10's, but had to come up with a slightly condensed version of what Steve made for his. What he made was just too big, so I had to come up with something I thought would work in my room.  I made a rough sketch and sent it to Craft Cuts. They took my drawing and fine tuned it so the radii would come close to what I had drawn.  They are making them now, and I should have them next week.  This is what they are making:


Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/13/19 at 22:17:28

What kind of wood Geno?

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/13/19 at 22:17:49

I ordered the Crystal's this afternoon.

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/13/19 at 22:19:29

Baltic Birch

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/13/19 at 22:22:03

Thickness?

And is this the place that does wooden letters?

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/13/19 at 22:35:59

Hi Pal.  1 1/2" thick.  Attached is the receipt for this for anyone else that might be interested. Not too bad considering the company is in Idaho and will ship them to Mississippi.  

I hope Mr. Randy is not upset about not coming to him with this :-[
I didn't want to take advantage of our friendship...

I'll have to come up with a base design. Something big enough that I can put a 10 lb bag of sand or lead shot on.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/13/19 at 23:23:13

Geno, what a great idea!  And seems like a very reasonable price.  How will you mount the driver?  Can they radius the opening front or back?  Just curious, how did you determine the hole size for the driver?

Title: Re: Steve's BIG BETSY Project
Post by deucekazoo on 08/13/19 at 23:41:20

Geno,
That is actually a really good price. When i was looking at wood, the price was in that ballpark just for the wood. The same Baltic birch but I would have some left over for the feet.  

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 08/13/19 at 23:57:05

Geno... Cool you were able to get Craft Cuts a whirl and have them build the baffles. Keep us posted to how they come out.  

My rings just shipped today.  Took them 7 days from the time of ordering to build and ship them.  Im not sure if yours will take longer or if that is just their typical lead time.  Either way, not too bad, especially for what you paid!

I just put the second coat of boiled linseed oil on my Bubinga baffles.  I contemplated staining them darker to better match the pedestal but the wood grain would have been muted and that beautiful Rosewood-like red tinge would have been trampled.  Too pretty to mess with mother nature so I put a couple additional coats of Linseed oil and will finish them up with a coat or two of beeswax.  They are looking great.  

For the baltic birch rings, I will be using a golden oak stain followed by the beeswax coats to create a two tone look.  

I still can't believe how hard this African Bubinga wood is.  It's definitely harder than many metals!  It will be interesting to see how the Crystal-10"s behave with this particular hardwood.  

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/14/19 at 00:03:32

Archie, the opening dimension initially came from Jeff who got it from the dude with Lii Audio. I verified that on the website. The plan is to mount it just like Randy mounts his on the Betsy’s. The speaker is placed in the opening and is mounted along the collar around the hole.  I did not request a bevel around the hole, but I’m sure that they could do that.

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/14/19 at 00:42:23

That’s great Jeff. I will look forward to your impressions. And thanks again for giving me the idea!  

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/14/19 at 00:48:57

Steve recommends a bevel to ease the wave front on it's way (rear wave in this case).  I put a 1/2" R on mine which are also 1 1/2" thick.  Do you think you'll use any gasket material between the driver and baffle?

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/14/19 at 01:05:34

I was about to ask about a gasket. Did you use one on your 15”?

I can see a possible need for a bevel with his drivers being recessed, but would I need it being flush mounted? Steve?

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/14/19 at 01:13:57

I don't think the recess makes a difference, just thins the amount of wood behind the driver.  Still the same size hole.

I didn't do a gasket but I'm open to persuasion.  I have some thin cork with an adhesive back that can be cut into narrow strips and easily formed around these large radiuses.  I first used it around the edge of my TT platter to slightly raise the edge so the clamped record would have full contact on the mat (compensates for warps) so I know it will form down to 6" R and likely smaller.  If the driver is rear mounted, like Steve's CR-10s, then there is a gasket already.

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 08/14/19 at 01:16:46

And interesting DIY open baffle article by the good folks at Hawthorne Audio:
http://www.enjoythemusic.com/diy/0709/open_baffle.htm

Title: Re: Steve's BIG BETSY Project
Post by BAndrade on 08/14/19 at 01:47:23

All this talk of the Crystal-10 full range driver is giving me ideas.

My next project was to upgrade the crossover in my speakers which have 5 drivers each and as many crossovers. Now instead I am mulling replacing 3 of the midrange drivers with one Crystal-10 driver thus eliminating the 3 of the midrange crossover and 3 drivers in one go. This would increase the efficiency of my speakers to above current 89 dB to some where in the region of 93 dB to 95 dB.

That would leave the tweeter (goes upto 45,000 Hz) and the bass driver (goes down to 24 Hz) and the full range Crystal-10 do the work in between.

I need to figure a way to strap the 10" Crystals to the speaker cabinets that are designed for multiple 7" drivers without modifying the current speaker cabinets. Alternately might just disable the 3 midrange drivers  leaving them on the speakers and placing the Crystal-10 as an open baffle along side.

When treading into uncharted territory I like to plan on reversibility and having not modified the existing cabinets I could easily reverse back.

I got to think long and hard on this because the chances are high that I might have phasing issues as the overlap in frequencies at either ends of the Crystal-10 could be significant. Perhaps a simple capacitor at the low end and an inductor at the top end to minimize the overlap might solve it.





Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/14/19 at 01:53:12

Archie, I’m glad that you mentioned the recess at the back. I see that the back of the driver will be sounding out of a hole with the baffle 1 1/2” thick. I think I’ll get in touch with the manufacturer and have them put a 3/4” chamfer on the back side to help with that. Thanks for pointing that out.

I’m going by the local stereo shop tomorrow and pick up some rubber gasket.  

Also, I have a question about the driver, and I’m calling China shortly to ask about it. I’ll ask about using a gasket too.

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/14/19 at 01:56:56

Jeff, I read that article yesterday. As a matter of fact, the post I made above has the highlighted segments from that very article.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/14/19 at 02:18:39


This afternoon we got a phone call from someone local who wanted to come by and see what we did. Initially he thought we were a stereo store, and I guess we kind of are. Anyway he arrived minutes after hanging up the phone, has vintage 15 inch speakers and has been looking for a good sounding amp for them. Discovered Decware about an hour ago and was shocked that we were so close.

We chatted for a bit and then I offered to let him hear what I was currently testing, the 25th Anniversary Zen Triode amp paired with the Crystal 10 Baffles. The speakers have a similar efficiency to what he has at home and 2 watts is usually enough for that, so it should make for a useful demo.

I played the Nexus track by Daniel Voth followed by Snow (Hey OH) by Luca Stricagnoli. He got up and walked into the hallway here and said "I'm convinced" and went straight to Sarah's office and purchased an amp. He'll be at DECFEST this year so add another one to the family : )

7 - 1/2 minute demo,  bought one. That might be a record considering he still has no idea who DECWARE is, so zero research, pondering, lusting... just completely spontaneously popped in here, heard it, bought it.

You gotta love that kind of efficiency. I think it's a pretty good testament to how good these sound.

Steve

Title: Re: Steve's BIG BETSY Project
Post by BAndrade on 08/14/19 at 02:43:05

As I was feeling to lazy to draw so I looked around on the www and found more or less what I had in mind. This is a picture from a site called Speaker Projects.
I mentioned this in an earlier post as well. I think a web at the back anchoring the unsupported top (especially for tall BBs) will increase rigidity thus preventing top edge vibes and loads transferred from the top to the heavy base.
Currently employing 1 1/2 inch thick panels is the option used. I think by use of framing the panel thickness can be reduced to 1 inch or even 3/4 inch.
This technique is employed in structural engineering a lot. e.g.if you happen to visit any gigantic super tanker that carry crude oil around the world and being pounded again and again by 10 m waves in the Pacific ocean and look at the hull from inside you will see a lot of webbing which allow the use of only 0.75 inch thick steel hull plating and yet withstand enormous dynamic loads. Without webbing the hull steel thickness would be as much as 3 inches to withstand that kind of pounding besides bending moments and shear loads of carrying 300,000 tons of crude oil.

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 08/14/19 at 02:44:03

Some here may be asking why it took even that long to figure out Decware was the right choice   ;)

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/14/19 at 02:53:57


Before we get too far into this let me remind everyone that the Crystal 10 is not designed nor ideal for open baffle use, not to mention open baffle use is likely a waste of the drivers bottom octave which I suspect is quite spectacular in the appropriate cabinet.

While I am having some good success with it in my Baffles, please note their size. In this size baffle the driver requires a ZROCK2 to sound it's best, similar to what it would sound like in a cabinet, but still without much of the bottom octave. That means to sound extra full and rich, a ZROCK2 is required which deals with a lot more than low bass.

Also, any smaller baffle will arguably have even less bass and require some kind of bass augmentation like a subwoofer set really high.

Because it is a lower Qts driver (0.5) as discussed earlier, it's stronger magnet limits cone movement at fs. thus limiting bass output. Since cone movement is directly tied to bass output in an open baffle design, it stands to reason that the louder you play the speakers, the fuller they sound. This is certainly the case with my Crystal 10 baffle design, meaning that playing at low levels without a ZROCK2 in some rooms will tend to sound lean and dry.  

None of this is the case with the Big Betsy and F15 drivers. Remember if it was possible to have it all in the science of audio there would only be one speaker and we would all have it. Honestly, the closest to that ideal speaker I've ever stumbled across is the Big Betsy baffles.

There is no question that if you modified this same size baffle to fit an 8 inch driver and installed the original Betsy driver in it, you would have a far better frequency balance at low volumes.  And interestingly, the original Betsy driver in the Caintuck Audio baffles being lower to the ground would have the same bass response as these larger baffles that have the driver twice as high off the floor.

I can safely say that the closest sounding driver to the Crystal 10 in an open baffle is the Caintuck Audio Open Baffles with the 8 inch alnico Betsy drivers at a fraction of the cost and half the size.    



Steve

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 08/14/19 at 03:05:50

Which mirrors what Leo of Lii Audio said with my question of bass performance comparing the F15's and Crystal-10's....

Hi Jeff,

Without doubt the 10" is much more "full range" than any other drivers thus if your question is about how bass it can go,  10" does better and is more elastic.

We highly recommend a cabinet of 220L at least or if you want to play with OB,  the OB should be big enough to allow the most performance.

Best regards,
Leo ZHANG
Lii Audio Team

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 08/14/19 at 03:13:02

For me, this is a ZERO risk venture.  I will eventually have a dedicated home theater room and I will assign these to front R/L mains since I will have a servo-controlled subwoofer to augment them.  

So, I will build these now, place them close to the front corners in my room to help "load" the bass and assess their performance.  If they suck, I store them until I move in the next year, or two (max),where they will be my new HT front mains. I think they will be absolutely perfect in that role since playing movies at dynamic volumes is what I enjoy!  Powered by by Decware Ultra preamp of course!

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 08/14/19 at 03:29:23

And as Steve mentions, everything is a trade off.  While a higher QTS will favor better bass, low QTS drivers mean powerful magnets and light cones, a combination which can result in better sound compared to high QTS drivers.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/14/19 at 03:31:51


Jeff, agreed, I think the lower placement to floor may well offset the baffle size a bit, and I think your application would be great as these things have absolutely startling speed with explosive marksmanship that would serve movies very well.  I'm actually looking forward to your impressions in the smaller baffles and to see where it leads.

For the record, the Lii Audio cabinets for these drivers are almost a give away and probably sound very good.  I've been tempted to order the complete speaker to see what is their reference.

Steve



Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/14/19 at 03:51:52


That Nexus track where the wood sound of guitar body being hit is so explosive and sounds real IF you were an elf about 12 inches tall and listening to it live about 4 feet in front of the guitar.  I've never heard anything like it with these speakers.  Well, that's not true, the FRX2 drivers will do it also, but these are 6dB more efficient and have a more organic sound due to the better cone material.  The last time I heard something spank like this, it was the FRX2 drivers with a ZMA driving them!  Now we have the same result from a 2 watt amplifier so it is exciting and going to be a game changer if this small Lii Audio company has the staying power and with two home runs under their belt, the F15 and the Crystal 10, and probably all of their drivers, I think they will have a long happy business.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Jeff of Arabica on 08/14/19 at 04:23:19


Quote:
IF you were an elf about 12 inches tall and listening to it live about 4 feet in front of the guitar.

I literally gut laughed big time when I read this   ;D

So, my plan is to drive these Caintuck Bubinga/Crystal-10 baffles with my ZMA..  

The way I am assembling these loudspeakers (cuz let's be honest, there were no saws involved on my end) allows for them to retain their original "on the floor" positions OR the raised pedestal mounted orientation.  I can switch from one to the other by simply unscrewing the (4) threaded brass weights that couple them to the "twisted" bases.  

That said, I will run them on the floor, on the pedestals, and in the room corners as part of my critical listening experiment.  Here a couple photos of the pedestal bases and the newly re-finished (linseed oil) Caintuck Audio "Bubinga" baffles.  The grain and color are simply intoxicating.  

The baffles are still waiting for the "golden oak" stained baltic birch plywood rings allowing the 10" drivers to join the party.

On a side note.... Randy at Caintuck, I have to hand it to you.  I have no clue how you managed to build these baffles out of Bubinga wood.  I tried to sand a small section on the rear of the baffle as I was exploring stain options.  I am pretty certain the baffle laughed it's ass off and promptly presented its middle finger to me.  That wood is possessed!!!




Title: Re: Steve's BIG BETSY Project
Post by Brian on 08/14/19 at 04:57:00

This is the earliest in the year that I can remember us having this much interest in Decfest!

Brian

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/14/19 at 14:20:39

Well, I spent another night and morning my attempt at Steve’s BBBs.  I am still very much in the honeymoon phase, but I still can’t find music these baffles don’t do well.

Last nights ‘oh shit’ moment was a Deadmou5 came on.  Hard hitting bass for sure  Typically I am tempted to switch on the subs for EDM type music.  But what I heard and felt I was very satisfying.  I’ve really only switched the subs on once since having these and messed with the cross-over point a little.  I was as high as 83hz, but now I backed it off to around 70hz.   Anyway, my current opinion is subs are a nice option to have with these speakers, but certainly not necessary.

The second moment was hearing Riders on the Storm.  That Rainstorm was bigger and more present than ever and covered the entire front wall of my listening room.  The music was more nestled in the storm, I thought.   I also noticed the overdub of Morrison’s voice more than I had in the past.  Finally, this morning, Cream, Live at Albert Hall – Stormy Monday.  Good live recording but the hit of the tight bass drum was notable. Pop Pop Pop

I did finally find a song that produced an unmusical resonance in the baffles.  I got up immediately and started feeling different areas of the baffle (as I am sure you all do).  What I can say with more certainty is my baffle with 1” oak is a transducer that you can feel in the listening position.  With my face maybe 6-12” from the top portion of the baffle, I could feel the same sound wave coming off of it for sure.  

Anyway, the part of the baffle that was producing most of the vibration and unmusical resonance were the sides, to the left and right of the driver, with the most vibration near the edges of the baffle and at the widest point of the baffle.  Not the upper part of the baffle as I expected or have felt before with my other OB baffles.  Not sure what to make of this except perhaps the shape of the baffle promotes the production of this sound wave??

With that said, I am entertaining the idea that resonance in these baffles, if at the right frequency, lends a more tactile pleasurable listening experience.  Maybe that’s a “no duh” kind of statement to you guys who have been at this a while but I’ve not felt this with any of my box speakers or 4 different OB baffles I have built/listened to.  I’m not sure how much of this I want to tame.  I am going to install the handles later this week and I will see what that does, if anything to improve or take away from the tactile feeling of these speakers.

Oh, and if you see some weird guy with his face near the Big Betsy’s baffles at the fest, that would be me, doing the transducer test.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/14/19 at 15:31:13

Pal, weights on the baffle will break up and change the vibration pattern.  You ought to be able to clamp something to the back at the sides to see what effect it has with that particular piece of music

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/14/19 at 15:48:27

Yeah, I could even clamp a clamp on it and see what that does.  I am not too concerned about it because its a single song so far that has the frequency prominent enough that it produced what I'll call dissonant baffle hum.  

As I mentioned before I thought after I glued up the wood that most songs with any bass would cause dissonant hum.  I thought there's $175 down the tubes.  But my experience has been very positive.  All in, I am at $625 and I am getting possibly the biggest return on audio investment I have ever received - at least for speakers I can say that for sure.

It's the bigger resonance picture that I am trying to understand.  Good vs bad resonance.  What to keep, want to tame.  I think I certainly want some resonance.  It makes music more live in the sense that it makes it more of a whole body experience.  And this baffle shape/size does it somehow.

Title: Re: Steve's BIG BETSY Project
Post by lazb on 08/14/19 at 16:03:03

probably a little off topic but planer jointer is different in Japan! Be patient and watch some of this video of planing competition in Japan!
https://www.youtube.com/watch?v=zs9X-XzFGHI

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/14/19 at 16:08:53

In a way it's a crap shoot.  I've been wondering if I should do anything at the bottom of my baffles in the way of a stiffener and/or additional weight/damping.  No particular reason other than Steve's build comment about using mass as a vibration drain at the base.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/14/19 at 16:12:56

lazb, try that with bubinga!  I didn't see a mention of the wood they were using but I couldn't even push a board that wide across my jointer let alone a hand plane.

Title: Re: Steve's BIG BETSY Project
Post by maddog07 on 08/14/19 at 23:12:04

Palomino…. “dissonant baffle hum”
That is exactly what I experienced with my Trio OB’s… there are two Hawthorne 15” Augie’s and a single 15” Audio Nirvana full-ranger in each baffle.  That’s a lot of “energy” from three 15” drivers to be controlled.  Even with the sand filled baffle rails, thick baffles, heavy felt cover… I still had “buzz” sometimes at some volumes.  The buzzing was worse, when I had ¼” plate steel outriggers on the bases with big brass footers (from Edensound) on the heavy outriggers.
That is when I tried removing the outriggers and brass footers.. sitting the OB bases directly on the floor – better – then the dense foam mats under the bases – better yet.  Then I added back braces, similar to what BAndrade shows in his picture above.  Except that I added two braces to each baffle.  One each close to the outside edges that run from the top to the bottom – instead of one down the middle as shown in the post from BAndrade. (I did use the one down the middle approach with my Betsy Baffles)  But even with two top to bottom back braces… I had some resonance from the back braces themselves occasionally.  So next, to further explore damping, I added clamps (Bessey clamps) temporarily in various positions to see if I could get all the objectionable resonances under control.  I think I’ve about got it all tamed down now – just need to finish/polish up the temporary additional bracing pieces.
FYI - 25lb bags of shotgun shot are great for damping experimentation also…..

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/14/19 at 23:15:33

Maddog, do you have any pictures of these can you can post?  They sound really interesting and it seems you've experimented with a lot of great ideas.

Title: Re: Steve's BIG BETSY Project
Post by beowulf on 08/14/19 at 23:54:47


Palomino wrote on 08/14/19 at 15:48:27:
Yeah, I could even clamp a clamp on it and see what that does.  I am not too concerned about it because its a single song so far that has the frequency prominent enough that it produced what I'll call dissonant baffle hum.  

As I mentioned before I thought after I glued up the wood that most songs with any bass would cause dissonant hum.  I thought there's $175 down the tubes.  But my experience has been very positive.  All in, I am at $625 and I am getting possibly the biggest return on audio investment I have ever received - at least for speakers I can say that for sure.

It's the bigger resonance picture that I am trying to understand.  Good vs bad resonance.  What to keep, want to tame.  I think I certainly want some resonance.  It makes music more live in the sense that it makes it more of a whole body experience.  And this baffle shape/size does it somehow.


Would something like this work from GR Research?

No Rez: http://gr-research.com/norez24x27sheet.aspx
Video here: https://www.youtube.com/watch?v=TJb8o6zzGi8

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/15/19 at 14:22:26

These speakers do all music well. One area they excel in is acoustic guitar based music.  I listened to some before I had these speakers and it was hard to get that into.  Nice if I was in a chill mood.  With these speakers, guitar music is enchanting.  I think I posted a Tidal playlist earlier.  Sounds wonderful.  I continue to add to it and added Steve’s guitar track.

So I have done some reading and generally, the purists say minimize vibration in the baffle.  Otherwise, you add something to the music that is not in the recording.  It seems people go to great lengths.  Even making baffles out of cement, marble, etc.  

I get where they are coming from.  I don’t think most of us go to extreme lengths to deaden their baffles.  But I am interested is seeing what it does.  I am just trying to wade through the suggestions to see what might be practical for me.

My OB baffle history goes like this…The first time I really heard a difference in a baffle (and enclosure) was when a forum member brought his DIY Pencils (sp?) to my room.  They were made of plywood and I thought to myself, what a wonderful tone these speakers have.  

Later, I heard Donnie's speakers which were MDF and had double baffles and took two of us to carry into my basement.  I thought, a heavier baffle adds punch and weight to the music.  So Raven helped me build some 1.5” MDF baffles. I liked those but they seemed a little dead to me, despite having some significant vibration near the top of the baffle.  They also seemed to block the sound behind the baffle.   That lead me to my Baltic Birch baffles (for tone) and the stepped baffles – smallest for tweeter, next biggest for mids and largest for bass.  Kind of looked like a skyscraper.  Those accomplished the dual goal of not blocking the music and providing good tone.

Then I go to the F15 in the low boy baffles (my 1.5”).  They sound really good, but I don’t think I am getting the full hit that Steve talked about nor the bass unless they are right on the floor.  So I build the Big Betsys out of hardwood.  Wonderful tone.  Sound great and I don’t want to transition back to my Baltic ply based speakers.  They also provide a whole body buzz even at lower levels that I feel enhances the enjoyment of the music.  So I’m not a purist.  I like the tone the wood adds and I like the body buzz.  

Still, I will experiment.  I did use blue tak to try to deaden the baskets on the drivers.  I didn’t feel or hear much difference.  I’ll try some other things suggested here.

I also think I may have figured out why the frequency response varied from the low boys to the Big Besty’s.  I believe it has to do with Baffle Step.  If I did the math right, the width of the baffles will add a few db in the 150-200hz range.  

Sorry for the long post.  I appreciate you guys reading and making suggestions.  There is definitely gold in them there hills.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/15/19 at 16:11:03

To deaden or not to deaden ...

I've been thinking about the bottom of my baffles and what Steve said about a mass drain for vibration.  I can buy 50 lbs of lead shot for $75.  I could make flat boxes that mount to my baffles at the bottoms and rest on my footer crossbar.  This would add 25 lbs of damped mass to the base of each baffle as well as add a stiffener to the bottom of the baffle.  

Anybody have ideas whether this is a good or bad idea?  Again, I'm not trying to "fix" any particular issue I'm hearing.

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/15/19 at 16:45:34

Archie, you could go the cheap route and fill some Ziploc freezer bags with coarse sand.  I'm going to try this first to see how it sounds.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/15/19 at 16:49:18

I thought of sand but the lead gives so much more weight/volume.  I think 25 lbs of shot fits into about 100 cubic inches (10"X10"X1").  Nice low profile.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/15/19 at 17:04:08



Quote:
So I have done some reading and generally, the purists say minimize vibration in the baffle.  Otherwise, you add something to the music that is not in the recording.  It seems people go to great lengths.  Even making baffles out of cement, marble, etc.  


Remember sound travels through solids faster than through air.  

The energy in the speaker baffle could therefor travel through the baffle and launch off the baffle without the assumed delay causing the entire baffle to become an extension of the speaker cone and with the same timing (phase angle).

Now, obviously if your baffle material is thin, has more than 3 open sides, or has a lot of connecting frames and hardware you are setting yourself up for a good smearing of the phase angle coming off the baffles and hardware relative to the phase angle coming off the cone.

None of this is going to happen with a solid hardwood baffle nearly 2 inches thick that sets on the floor and has curved sides. This is what I've been trying to illustrate with this project. By enlarging Randy's baffle design we can start to understand it's magic a little more.

The body buzz comes from the speed of the baffle as a transducer in so much as the x-max of the wood itself is probably .001 so there is no overhang or slop from the sound it launches and the wave launch is larger than the listener x 2.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/15/19 at 17:15:29

Archie,

The fundamental difference between you and Pals base design is the contact points with the baffle -- there are two spaced apart.  

To drain vibration evenly from the whole baffle, the base should make contact across the entire back side at the bottom similar to the ones I did.  

My advise would be to just fill it in with hardwood (glued in place). Tossing a bag of sand or shot on the base when it's all finished could only help.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/15/19 at 17:22:52

Thanks Steve.

I totally believe that the wave off the baffle is more than 2X my size.  It feels like it fills the room.

I could easily add hardwood across the two braces, making contact with the bottom of the baffle.  I could even add a box of sorts (two pieces plus a bottom) which could be filled if that makes sense.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/15/19 at 21:58:01


Quote:
My advice would be to just fill it in with hardwood (glued in place). Tossing a bag of sand or shot on the base when it's all finished could only help.


That's pretty much what I had in mind to try.  I'd build a box with the side that attaches to the baffle being maybe 2 1/2"X1 1/2"X the space between the footers.  The rest of the box would be just to hold lead shot in a clean looking way.  By the time I do this, my speakers will weight over 100 lbs each.  I'll either take them off the isolation platforms entirely or beef those up considerably.  I have heavy felt pads on the footers already so they will still slide on my wood floors fairly easily.

As I posted before, I missed the original remark about base function and mass.  Doh!   [smiley=simp48.gif]

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/15/19 at 23:10:02


Archie, it is good that you missed it, because we got to find out what happens as a result., while the jury is still obviously out on that, we have found out that the  baffle still works and sounds very good which is to say the design seems to be a forgiving one.  I think that's helpful to anyone reading this thread who might be considering building a pair.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/16/19 at 04:41:11


Tonight I decided enough casual / handicapped listening.  Time to clear some speakers out and put the new Anniversary edition CSP325 preamp into the mix.



By placing the Big Betsy next to instead of 90 degrees behind as you saw in the previous picture, and adding the preamp, everything has transformed into a wonderfully full, wide sound.  The bass came up with the Big Betsys moved to the new location.  Normally of course they wouldn't even be in the room, but right now I have nowhere else to put them.  

The preamp really takes the 25th Anniversary Zen Triode to the next level, as it should since the combo is double the price of the amplifier alone.  If it didn't make you go "holy crap" then it really wouldn't be worth the money.

So this evening as I randomly browse through material, nearly everything is sounding better than ever!  It's like nothing can get dry now, and the detail and presence is simply exquisite.  

Right now I am listening to the Bach Cello Suite 1 (prelude) by the Stanley Clarke Band from their album titled "The Message" in 24bit and I have to tell you the Cello in this recording - the sound shouldn't be possible from even 24 bit digital but yet I'm hearing it sound like tape. I attribute this primarily to the addition of the CSP325 preamp. I am certain had I played this last night before the changes I wouldn't have thought anything about it. Tonight however, I hear it and it's like seeing a leaf up close for the first time. Just incredible. The texture and tone and the imaging is so dimensional that before I could hear the face and sides of each sound source, but now I can hear a wrap around effect that just breaths making everything more sharply focused in 3D space.  The effect is when you move your head instead of hearing the performer move left or right, you now just hear more behind him on one side or the other and he doesn't move, just like in real life.  As you move your head, your perspective changes, not the position of the performer.

I knew to make these changes before I ever even auditioned these speakers, but I like to work from handicaps to see what it might sound like in less ideal circumstances. The frequency balance was right on the edge of being great and more recording / ZROCK dependent than I would have liked, but the other baffles were cancelling a lot of the bass which is what caused this condition. Now that they have been moved there is significantly more bass and overall warmth and of course the imaging is now boundless.  

This is really good, and I mean REALLY good. I'm pretty sure the Big Betsy baffles setting next to the Crystal 10 baffles are sympathetically contributing a touch of 50Hz body, and I don't even care because I'm delirious with sonic pleasure and if that's what it actually took than so be it. Time will tell, hell, they might still be killing bass for all I know. You wanted to take this journey in real time with me, so there you go.

I haven't listened to the preamp for the past few weeks to clear my head of it so I can do an objective final evaluation before we start production next week. I am so glad to have it back! Wow, it just fixes everything. I didn't even know half the recordings I had were as good as they are! That's the scary part. There are many recordings that got to go set in the corner after having offended at least one of my sensibilities on some evening... Then I try them again, like now, and I have to waste a lot of time researching the label of the actual track release to see if it is the same recording because it sounds so different. We're right in there with my vinyl rig now, which is rare. That really is worth the price of a preamp if it's the right one.  At least it is to me.

Also, I have never heard the preamp on drivers this good, so I feel like I'm hearing it for the first time tonight and I'm damn impressed. It's just so amazing how it takes a somewhat chaotic sound quality and just tightens everything up, organizes it, and fixes it so that the amp can be played as though it had over twice the power with no danger of clipping whatsoever. It actually does what a ZROCK2 does to restore body and tone but in a completely different way.

In total, this system is pretty expensive, probably 6 or 7 grand for the speakers and ZROCK2. Another 6 or 7 grand for the amp and preamp.  But I can tell as someone who has heard a few systems including those at ten times this price point, this delivers the goods.  It's is exactly the famous Decware Zen Triode sound that anyone can buy for $998. and a pair of speakers, but the sound has been magnified in the same way the Hubble Telescope transformed astronomy. There are no earth based telescopes that can even get close.  


Low volume listening has improved by 60% or more since my last posts on that topic. I attribute that to both changes, but am surprised nonetheless by the rather dramatic improvement. Possibly everything I said earlier about having to be played loud was complete crap. We'll see. Tonight might just be a dream for all I know... a damn fine one I can tell ya.



Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/16/19 at 05:01:11


I swear to God, I just felt the scorn of a jealous woman that had been cheated on by my favorite overall daily driver speakers, the DNA2's. Wow, that was really weird. I get it though. I think they are pissed.

I explained to them they got nothing to be jealous about, just as the 72 Monte gets more looks and attention than any Porsche which is many times it's price.

Steve

Title: Re: Steve's BIG BETSY Project
Post by dank on 08/16/19 at 15:39:03

Long post coming up:  F15 OB vs Beolab 8000 shootout

About 4 months ago I offered to repair a speaker that belonged to a friend of my wife.  What showed up was a pair of Bang & Olufsen 8000's, also referred to as Beolab 8000's, one not working and one fully functional.  They are a pencil shaped powered speaker that is going for about $1000 a pair on Ebay.  When I first saw them I figured they couldn't possibly sound good - small volume aluminum enclosure with a port - how could that work?

I dove in and fixed the problem - decomposing foam, due to age, turns acidic and eats away the 120 vac trace that powers the main transformer - easy fix (although fairly messy due to the foam goo).  Once working, I was quite impressed with their sound.  So impressed, that I bought a single, not working, speaker that was on auction on Ebay.  That one had a bad standby transformer, $17 for a suitable non-OEM replacement part (including shipping).  I then started looking for a 2nd speaker.  Two months ago, a broken amp/power supply showed up on Ebay at a price I couldn't turn down, so I bought it for spare parts.  It also had a bad standby transformer.  Finally, a second non-working speaker appeared on Ebay and I got it.  It came two days ago, and I got it fixed in about half an hour - same eroded foil on the circuit board due to decomposing foam.  Now the Beolab 8000's are set up next to the big F15 OB's for some serious listening.







The Beolab 8000 speakers take a line level input, so it was just a matter of turning down the volume (way down) on the Zkit60 amp I'm using to power the F15 OB's to get equal volume for A/B testing.  What I heard shocked and surprised me.  The Beolab speaker is a good speaker, very good.  It was sold from 1992 to 2010 (18 years) without significant change and still commands about $1000/pair on Ebay.

But...

I never would have bought them if I had the F15's in the big OB's to compare them to when I first heard them.  Note:  I did have the corner horns.

The detail of the F15's is sooo superior that its not even debatable.  And, of coarse, the sound stage is quite a bit bigger.  I found myself listening to songs on the F15 OB's, picking out something - like the strike of a cymbal, and then going to the Beolab's.  It was there - but you really wouldn't pick it out unless you were listening for it.  With the F15 OB's it was right there in your face.

I next configured the spectrum analyzer and white noise generator to see if that would tell me anything more.  If it does, I'm not really seeing it.  If anything, I would say the Beolabs should sound better than the F15 OB's.  But they don't, not even close.


Beolab frequency response:




F15 big OB frequency response:



Note:  subwoofer in place for both speakers.


Just another testament as to how good the F15's in the big OB's are sounding.

Dan


Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/16/19 at 15:56:04

Dan, I was wondering about that low end for both on the graphs.  That's the subwoofer then.  You haven't posted much about your F15s but is sounds like you're getting similar results as Steve, Pal and me.  4 different baffle builds too!

Steve, just to be clear, your write up is for the CR-10 drivers, yes?

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/16/19 at 16:38:55

Thanks for the comparison dank.  Yeah I saw that chart and said “what???”

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/16/19 at 17:32:58

Yes, the Crystal 10 baffles are what I was writing about.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/16/19 at 18:35:42


Dan,  it's really a great illustration of just how useless frequency balance measurements are ; ).  Or put another way, how nearly impossible it is to tell how something sounds from looking at one.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/17/19 at 03:49:13


So It's Friday, and I'm back online with the Crystal 10 baffles... Big Betsy Juniors perhaps... and things are sounding sublime. This despite an attack from the underworld that tried to derail things.

You can read about it here:  https://www.decware.com/cgi-bin/yabb22/YaBB.pl?num=1408725911/787#787.

It is a post about why I believe in father Murphy and what I know about him.

This morning I had a listening session where the DNA2's were to be paired with an SE34I.5.  No irony there. They sounded extra good. No irony there either ; )

We actually did a few side by side comparisons with the Crystal 10's and the DNA2's that I found interesting. The Crystal 10's actually came off as having more hit and more base weight, and that was volume matched. 6dB more efficient wouldn't be a fair fight, so I turned the amp down when the Crystal 10's were in play. When we would put the DNA2 back in, there was a sense of loss in the overall bass although the DNA2 had lower bass that was easily appreciated, it didn't matter because it was just too polite. Anyone reading this who has heard DNA2, there is no deficiencies in the bass or anything else.  It's a nearly perfectly balanced speaker with nearly perfect imaging. I have to admit I was surprised by this comparison. The SE34I.5 was used with 6L6 tubes and no problems driving either pair of speakers to the same volume that we wanted to hear in the room.

I think I will call these the Big Betsy Juniors (BBJ) so that like the Big Betsy, the name honors Caintuck Audio's Betsy baffle shape. And speaking of which this couple wanted to hear the 'little ones' referring to my personal pair of Wenge/Paduke Betsy baffles with the alnico drivers. I told them that the "little ones" will actually create an identical size soundstage as the BBJ they just heard and have a similarly refined sound. Hehe... you should have seen the look on their faces when I was right.

In fact I thought that was the best Betsy Baffle speaker demo I've ever given. First setting the bar at the very top with the BBJ and DNA2 and HR1 speakers and then setting the Betsy Baffles down there and literally sounding equally good. I just found it interesting and impressive as I know they did as well.

I am starting to have little doubt that this baffle design of Randy's is likely the best open baffle design in the world. It looks deceptively simple but it really isn't. I know one thing, and Randy knows this as well, and that is that this baffle design will slowly get under your skin and you will become less and less tolerant of lessor speakers until you are so spoiled that you don't want to listen to anything else. Or should I say can't listen to anything else.

It is amazing to me that this entire project came from simply wanting to have some fun scaling up the baffles Randy made for me and sticking a 15 inch woofer in them for some subtle bass augmentation. It was wildly successful. But in the process of looking for the perfect 15 inch driver for bass augmentation I cam across the Lii Audio F15 driver and knew instantly that was going to be really good. Even though I had no use for it, I had to get them. I knew I could put them in the Big Betsy Baffles I just built and have some fun listening to a giant version of my "little ones" as my guest this morning calls them. Of course I had no idea how insane that was going to actually sound, but it has set a new benchmark so far as I've never heard a speaker do the Big Betsy Baffles do or be so satisfying on such a deep and complete level across such a wide range of music.

So because of this incredible result, I had to try the "expensive drivers" from the same company, their reference 10 inch full range called the Crystal 10. So now here I sit with two new references, both 100dB with 1 watt and interestingly enough, my original Betsy Baffles now have the exact same added bass texture that the original plan was intended to give, only now it's even better because instead of having a supplemental baffle driven by the same amplifier, we have a supplemental baffle being driven by sympathetic resonance, which is always perfectly in phase across the entire angle and requires nothing but the air in your room... no amplifier is used.

That is why this morning when we put them on, they literally sounded as big as the BBJ and had the same bass output! See, I couldn't have predicted this outcome, having all three pairs of speakers work so well together is like having your cake and eating it too! I can now go back and forth between the original Betsy with the Alnico drivers from Caintuck Audio and the BBJ with equal pleasure. It's like tube rolling only with speakers.





Steve

Title: Re: Steve's BIG BETSY Project
Post by Showme on 08/17/19 at 14:14:57

I have to wonder what the designer's Crystal 10's sounds like in the enclosure they designed and offer it in? They look pretty interesting.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/17/19 at 17:42:18


Quote:
... interestingly enough, my original Betsy Baffles now have the exact same added bass texture that the original plan was intended to give, only now it's even better because instead of having a supplemental baffle driven by the same amplifier, we have a supplemental baffle being driven by sympathetic resonance ...


Am I understanding this correctly in that the big baffles, just being near the Betsys but not powered, augments the bass?

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/18/19 at 01:31:53

Yes, I'm pretty sure it does.  Time will tell when I take them out of the room.   I'd really be impressed with the BBJ if the bass stays the same without the BB in there.

Steve

Title: Re: Steve's BIG BETSY Project
Post by will on 08/18/19 at 01:55:02

I wonder how much burnin plays into this? One of the Crystal reviews on the Lii site said his were still changing after a couple months and it does seem bass would be a pretty big player as the drivers loosen up.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/18/19 at 03:54:58


Will,

If that's true it can only get better. I am so used to gauging break-in by hearing the fibers in the cone loosen up and relax enough to minimize the "cone sound". I always thought that took longer than the suspension loosening up, but I suppose I'm guilty of not wanting to realize that every driver will be different. In the case of this one, since I couldn't hear the cone on minute one it has really thrown me off. I'm listening to some simply recorded Elvis music right now and am really impressed with the sound.  

My favorite thing about these Big Betsy baffles with the Lii Audio drivers is the efficiency.  It allows me to 'rock out' sort of speak with a 2 watt Zen amp in exactly the same way that the 94dB speakers did on the TORII or ZMA amps. Because it is the same, it is not the same.  It is far more satisfying to constantly remind yourself that this is happening with 2 watts than it is to know it's happening with 40 watts.


Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/18/19 at 04:10:11



Quote:
I have to wonder what the designer's Crystal 10's sounds like in the enclosure they designed and offer it in? They look pretty interesting.


I have the plans for those, and they do look very interesting. More of a vintage ducted cabinet design.  Of course the curved panels would reduce panel resonance. Anyway I have the same curiosity. And considering what the Betsy Junior's could cost done in hardwood and with a ZROCK2, it would be easily half the price.  I may look into a pair before it's over.  Then again, even with lower bass, it's getting harder and harder to imagine them sounding better than they do in these thick hardwood baffles.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/18/19 at 04:31:38


I can see where this odd shape would actually reflect all the internal waves to the center where the energy would be get canceled.



Very little would actually ever hit the back of the cone, which is what you want with any full-range driver.



Hey Bob, ever seen a wood veneer bent around an 1/8" radius?  

-Steve

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 08/18/19 at 05:48:40



Steve wrote -


Quote:
I am starting to have little doubt that this baffle design of Randy's is likely the best open baffle design in the world. It looks deceptively simple but it really isn't. I know one thing, and Randy knows this as well, and that is that this baffle design will slowly get under your skin and you will become less and less tolerant of lessor speakers until you are so spoiled that you don't want to listen to anything else. Or should I say can't listen to anything else.


Wow !!! ..... that is high praise from someone who has forgotten more about loudspeakers and loudspeaker design than I will EVER know .....

After building literally dozens of open baffles via the trial and error method, the "barrel" shape seemed pleasing to the eye and musical to my ears ..... it appears that the sum is greater than the individual parts, by several orders of magnitude.

I have never made it a secret that the low powered Decware amplifiers are still my favorites out of all the amplifiers in the line. From the first time I heard a "Zen model B" in my listening room and a "Select" was purchased, it totally changed my perception of what a really good amplifier sounded like ..... tonality, speed, a three dimensional soundstage, etc.

The only requirement is a pair of loudspeakers efficient enough to reveal what the amplifier is providing. A high efficiency full range driver with no crossover components in an open baffle fills this requirement very nicely.

The synergy between both the Wild Burro Audio Labs and Lii Audio drivers and the SE84UFO has kept me pinned in my listening seat for the past few weeks ..... and Steve is right ..... I have no desire to search for other loudspeakers. I certainly realize that there are many fine loudspeakers available ..... but there is music in my listening room and I can't ask for more than that .....

The first orders for the "baby" Lii F-15 baffles will ship this coming week.
I'm hoping that the recipients enjoy these speakers as much as I am.



I'm really looking forward to being in East Peoria in October to see what effect the ZR2 has on these baffles .....

This will be a Decware Fest to remember .....

Happy listening,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/18/19 at 17:56:01


Quote:
Yes, I'm pretty sure it does.  Time will tell when I take them out of the room.   I'd really be impressed with the BBJ if the bass stays the same without the BB in there.


This got me thinking about telescopes.  Large observatory telescopes don't depend on huge primary single mirrors anymore like the Palomar but rather use arrays of smaller mirrors like the Keck.  I wonder if a driver surrounded by smaller baffles ...   :)

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/19/19 at 04:27:12


Tonight I played the Big Betsy F15 combo and it was like a welcome friend. The frequency balance is so nice in the low end as we all know. But after having listened to the Big Betsy Jr. with the Crystal 10 driver for the past couple weeks, the Big Betsy sounded a little dull/muffled by comparison. That's OK, because I told myself if I had to choose one or the other, I would have to choose the Big Betsy.

Less than 1 hour later, I found myself craving the sound of the Big Betsy Jr so I switched over. I had turned off the ZROCK2 during the Big Betsy audition, so to be fair, I left it off. Yes, the BBJ was leaner but more open sounding. I created a cardboard box (12x12x14) with a slot in it and placed it just below the driver. It actually worked somewhat but I abandoned it rather quickly. It's as if I knew it was creating a disturbance in the force or something.

I imagine the marble pool of water the Audio Gods look into when they are watching me probably had pretty good ripple in it catching their attention. Then you would have heard one of them yell out, "Hey, look what this idiot is doing to our speaker design!!! Holy Crap, we have to do something!"

About that time a vision flashed into my head of what I should be doing there. My guess is they fell asleep waiting for me to figure it out on my own. Anyway I have this pick-n-pluk foam that is 1/2 x 1/2 x 2 inch squares cut 98% of the way through a solid block of foam. It's like a super absorber.

So I simply set it place and was stunned at the difference it made. It did more to even out the frequency balance and warm things up than I was expecting. I am experiencing (the illusion of) more bass than I was from the tuned cavity box experiment that caused such a ripple.

I've been listening to it for nearly an hour without the ZROCK2 and have forgotten repeatably that it's not on.  I love this solution, sad I didn't think of it, but nevertheless it's so Zen.  It just sets there.






Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/19/19 at 04:28:16


Here is another view of the foam block



Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/19/19 at 04:51:20


So as the evening progresses with the foam blocks I am really surprised at how much better I like the sound. It's stunning really. My first impression is that this was a scale tipper. The Big Betsys are probably in trouble. Time will tell, but man...  

You know if this close proximity reflector being eliminated and replaced with a mid-bass and high frequency absorber can make such a huge difference in a room that is fully carpeted...

It really demonstrates my desire to hear this driver in a top tier open baffle design so there is zero sound hitting the back of the cone from a box or nearby surface. From what I am hearing tonight, going to a well designed enclosure like Lii Audio makes for this driver would trade low bass and mid bass hit for openness.   Hehe, just a few posts ago I was contemplating buying a pair and now I'm contemplating not buying a pair... all because of a divine block of foam.

Steve



Title: Re: Steve's BIG BETSY Project
Post by Bottlehead on 08/19/19 at 05:58:21

Love the experimentation, Steve. It seems like it just keeps getting better and better. Can't wait for the next installment.

Title: Re: Steve's BIG BETSY Project
Post by will on 08/19/19 at 06:18:59

Great news Steve! Nice discovery.

Title: Re: Steve's BIG BETSY Project
Post by Bottlehead on 08/19/19 at 06:57:07

Steve, I'm envisioning a resonator box on the back of the baffle, ZOB-style, with the top surface covered in the same absorbing foam around the sound hole. A bass reinforcer. Thoughts?

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/19/19 at 13:58:34

So I went to the cottage in Michigan this weekend.  I have a nice second system there: Macbook to Chord Qute DAC to modified Rachael with 807 tubes.  The speakers are Betsy drivers on top of Augies in a traditional shape baffle.  Augies are run by a plate amp.

It took me a while to get it dialed in but once I did, it produced decent sound.

Then I came home and listened to the Big Bestsy Baffles.  My first thought was how easily these speakers produce such good sound.  No fuss, no muss.  Granted, I have a 25th at home and a treated room but still….just effortless.

Big Betsy’s for the cottage would never pass the WAF so I need something smaller and certainly no larger than what I already have in place.  Those are even pushing it.

On the Big Betsys I also have weights now on all 4 of my braces.  About 5 lbs each.  These will do until I can build a structure to attach to the baffle.  I also put a piece of foam down below the driver.  I felt the weight helped the slam a bit.  Not sure about the foam.  I’ll need to do some comparisons.

My son did stop by to test his most recent EDM creation.  Sounded good.  I did turn on the subs for this one.  He liked the drivers overall and loved the soundstage.  He did feel it missed a little something at the top end.  Of course, he can still hear and he was used to the speakers with the AMT/supertweeters.

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/19/19 at 14:57:14

Steve, I put thick felt all over the back of my Lil' Betsys a few weeks ago, and this has made a very definite difference. So much so that I have more felt ready to put on the new Crystal 10 baffles when they arrive.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/19/19 at 15:17:42

Hi Geno,

What was your source for the felt?  Fabric store?  How thick?

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/19/19 at 15:43:59

Pal, I just ordered 3 or 4 (6 sheet pack) of 3/16” felt on amazon. Any thicker than that and it is hard to cut to shape. You will just have to figure the area to know how much you need. As big as the Big Betsy’s are, the reflection that is present now would be greatly reduced.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/19/19 at 15:45:36

Thanks Geno!

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/19/19 at 20:40:56


As I mentioned earlier in this thread, the frame of the betsy driver is the only problem with sound coming off the back of the Betsy Baffle, not the rear of the baffle itself.

As far as reflections go, any sound that hits the back of the baffle from room reflections, will reflect back away from the listener actually enhancing the ambience and have no effect on imaging focus except to possibly improve it.

The sound of these baffles is directly tied to the wood itself. Putting felt on it would be somewhat like putting felt on the speaker cone.  

None of this should be confused with the foam absorber placed on the base of the speaker. I would rather see people gluing felt to the walls of the listening room ; )

All of this is of course based on the assumption that a "live" baffle is going to sound better than a "dead" baffle. We sill need to make a co-mass-layer-dampened baffle to compare and see what happens, or de-couple the driver from the baffle or some degree of both to really find out.

I just don't want the 4700 lurkers of this thread to get felt happy without some degree of caution. The science is simple if you want to really find out.  It only take two speakers. You do something to one an not to the other and then objectively compare the two.  

Tweaking a stereo system is like going for a hike in the woods.  It is all to easy to make big changes without the comparisons and then loose track of where you came from and ultimately end up lost. This is what is meant when audiophiles who have been in it for 40 years or more say that they had it once or twice but lost it along the way and never got it back.  (Had it not been for Decware they would have died in the woods.)

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/20/19 at 04:01:50


ZROCK2 EFFECT : )

So last night, and you'll probably love this, I allowed myself to fully experience the potential of a ZROCK2.  Which sounds silly considering I am the designer of it.  That said, the majority of testing I've done with it over the years has been on speakers that didn't actually need any help in the base, so when I adjusted the ZROCK2, I would always find the magic point of the highest treble at about 2 o'clock and just tease the signal a bit with it. In other words, I was just fixing recordings with it.

Last night I reminded myself, that it's OK to actually use the damn thing, so just turn it up and see what happens!  

The tone became so large that music sounds like a Normal Rockwell painting just dripping with tone and liquidity... the exact opposite of what we usually get with razor fast full range 100dB speakers!!!  

And when you hear it, that the rich warm full round wet sound with the ZROCK2 turned up a bit more has easily allowed these speakers to come into their own in this particular design. Add to this the incredible benefit of being able to actively adjust this sound with a pure class A zero negative-feedback single-stage single-tube EQ instead of getting involved with multiple drivers or passive networks, we persevere the holy grail of a single-voice-coil full-range experience.

We're talking about the Big Betsy Jr (BBJ) with the Crystal 10 drivers just to be clear.  Set like this no-one would believe these were open baffle speakers.  Same thing that happens when people hear a Big Betsy, and that was after all the goal, to downsize the Big Betsy but maintain much of it's low end effect while increasing the Treble transparency.

The speaker will pass on it's own without a ZROCK2, especially on good analog systems or digital systems with a really great preamp. That said, the ZROCK2 is an insurance policy and can be adjusted to your taste while you listen. It allows you to not only in this case fix your speakers by giving them more bass, but going beyond that and fixing bass shy recordings on the fly as needed. This is because the room speaker combination is fixed at a certain setting and thin recordings played on this system are fixed on the fly with additional correction.

In practice, since I usually listen to well recorded music, once I find a setting on the ZROCK2 that works, I leave it alone.  The exception is when I want to hear something that sounds too lean to be enjoyable, then I can just fix it.  It turns out that this fully opens up your music library.  The pile of music you don't care for vs. the pile you like can be defined by the weight of the music. Being able to fix that issue so easily leaves only content so now your pile of music that sucks just shrunk to half of it's original size, and your pile of music you like just grew by the same amount.

I can be certain that a ZROCK2 would be helpful for any open baffle design that uses drivers with a QTS below 1. Drivers with a high QTS around 1 or more can still benefit from it, the lower Q just magnifies the ZROCK2 effect so less correction is needed.

When you consider the alternative, subwoofers, bass augmentation, partial enclosures or stupidly large baffles or horns, this not only makes financial sense but common sense as well.  

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/20/19 at 04:35:26


So in marveling about the shape of the Betsy Baffle from Caintuck Audio which I scaled up to really understand -- and how it outperforms the same sized rectangular baffle that by the math isn't possible... you know when you hear this kind of bass coming out of a flat boxless device that looks this good it bends your mind pretty hard -- those curved sides and offset driver.... then it struck me!

It's an egg.

The driver is the yoke.

It's all starting to make sense now...  

Leave it to a hillbilly wood-butcher, to duplicate nature. I was trying to do it a year or two ago with the EGG omni speaker, and here were are once again, dealing with an egg. This one is flat and sounds round. The round one you expect to sound round. When the flat one sounds round, you wonder how.

Never underestimate eggs.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 08/20/19 at 14:38:24




Quote:
Leave it to a hillbilly wood-butcher, to duplicate nature. I was trying to do it a year or two ago with the EGG omni speaker, and here were are once again, dealing with an egg. This one is flat and sounds round. The round one you expect to sound round. When the flat one sounds round, you wonder how.


I resemble that remark .....

Happy listening,
Randy the Hillbilly Wood Butcher


Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/20/19 at 15:09:49

Any advice on finishing these baffles?  I usually just hit them with a dark (almost black) stain to cover my imperfections and let it dry and then a couple coats of poly.

I don't want to do a golden oak kind of thing.  I may want to leave them as natural as possible.  I guess I want to bring out the grain but not color them too much.

I have never worked with linseed or tung oils of any kind.  Any suggestions are appreciated.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/20/19 at 16:23:52

Steve, It's good to see you enjoying YOUR ZROCK2 ... Finally!   ;D

I have the stiffened shot boxes installed on my BBs (waiting for the shot) and I think that's improved the bass response already.  I find that I am turning down my ZR2, even compared to where I had it with my HR1s.  I was listening to Pink Floyd's The Final Cut last night and I think I was hearing about 30% more in the music.  Really incredible.  The extra texture and sound I was getting was unbelievable.  I kept expecting things to break apart with the huge impact from the sound but the BBs just kept on giving.

Pal, I recommend linseed oil if you want a no nonsense natural finish.  Just wipe it on and keep everything wet with it for 15 to 30 minutes (keep applying with a wet rag).  You'll really see it getting absorbed by the end grain.  Then buff it off.  You can add more coats in a day but I rarely do.  Make sure you dilute the oil with 30% to 50% paint thinner to allow it to penetrate better.  You can tint the oil with stain but I rarely do that.  Linseed gives a natural golden hue due to the color of the oil and how light effects it after it cures.  You have to see what it does to cherry to really appreciate how beautiful a finish it can give.  BTW, eiter submerge the used rags in water, burn them or spread them out flat to dry.  Crumpled up, they WILL start a fire.  Ask me how I know!   :P

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/20/19 at 16:25:38

Thanks Archie.  I think I will give it a try.  I loved that look on Steve's baffles.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/20/19 at 16:44:19

Sometimes oil will seep out in the first day so keep a rag around to do a little occasional buffing.  The only thing to watch for with an oil finish is that if you leave a film to dry it will get hard like shellac.  You can always buff with 0000 steel wool at any time too.  I'd stick with 100% linseed or tung oil -- not "oil finishes."

Title: Re: Steve's BIG BETSY Project
Post by Lon on 08/21/19 at 00:53:16

Doesn't surprise me that the ZROCK2 ha a profound effect on the sound with these speakers.

I've been hamfisted with mine in both systems, and I get addicted to the creamy textures and body to the sound, making the small combo jazz I mostly listen to sound so full and rich and the instrumental images so vivid and closer to real.

I won't let mine loose and I'll have one more for my third system one day I'm sure. This device, along with the ZBIT, have changed the game in my istenening world.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/21/19 at 02:43:18


Lon, it's particularly nice with fast and unforgiving speakers I've noticed.  Glad you're enjoying them as much as I do!

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/21/19 at 02:53:38


Still digging the foam absorber.  Today I noticed another result from it.



All of these open baffles I spend some time listening to from the back side and comparing what comes out of that as opposed to the front side.  Not only frequency balance, but sound quality and imaging.

The frame design of the Crystal 10 is the best I have used. The way the spider comes to a seamless edge and the sound just rolls down the magnet cover is as diffractionless as a speaker can be made. And I have been noticing over the past weeks how good the Big Betsy Jr. sounds from the rear with this amazing driver.  It sparkles!  

Today I stood in the doorway behind the speakers and listened and it was truly spectacular, some would confuse it for the sound coming off the front. Identical sound in fact, just a tiny bit rolled in the rear. The foam really made things better from this perspective which is good since this is the sound that hits your walls and then hits your face. You hear it, believe me.

On a completely different note, I made an astounding discovery that confirms my suspicions about the wood becoming an transducer. In the picture above you can see the large cast iron handle. When standing with an ear biased to the front side of the cabinet at standing height, putting my hand on the handle makes an obvious difference in the sound of the high frequencies. The highs sound noticeably better with my hand off the handle. When the hand is on the handle the highs diminish from this extreme off axis perspective.  This is on the Big Betsy Jr., Crystal 10 baffle.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/21/19 at 03:28:01


Randy,  I'm so happy that you have this free-standing zen space in your back yard!



I got serious about listening and this hobby when I was living alone after my first wife dumped me ; ) I had about 17 years of total silence and total focus to work from so music was a glorious distraction free experience.  I have a similar experience now in the Decware listening room / shop which is why I have never spent even one hour listening to my stereo in the house.  I guess, I'm saying I know what it's like to have a listening chapel that is just yours and I really enjoy seeing the pictures.  If we didn't know better we would think this was in Japan.



Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/21/19 at 03:40:20



Quote:
Steve, I'm envisioning a resonator box on the back of the baffle, ZOB-style, with the top surface covered in the same absorbing foam around the sound hole. A bass reinforcer. Thoughts?


Had to ponder this awhile.  As mentioned I did model this out of cardboard and it did have an additive effect like it does on the ZOB.  My thoughts are that on this baffle it really isn't needed and while it would likely increase the bass and texture it would really kludge up the design and as delicate as the sound is coming off the rear you have to ask yourself would you put a box just under the driver with a hole in it and foam in the front of cabinet?  Same thing.

I do have an idea for a way that it could be done that might work a lot better than what I did with the ZOB and be largely invisible.  To do it in hardwood would take a CNC machine, but layered MDF or plywood could make it possible to do with normal tools so we will see.  Right now it's just way less expensive and a cleaner look to just add a ZROCK2 which gives numerous other benefits beyond bass correction and is adjustable.

Steve



Title: Re: Steve's BIG BETSY Project
Post by Bottlehead on 08/21/19 at 05:38:46

Well then, I see another ZRock 2 in my future, as the one that you just modified for me is in my Betsy Alnico system, and it's NOT coming out.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/21/19 at 16:54:38

I finally got the lead shot installed at the base of my BBs.  I built a box with a 3 1/2"X1 1/2" piece of maple on the baffle side to act as a stiffener and I screwed it into the baffle.  Before doing that, I lined the free floating contact surfaces with cork.  I filled the box with 25 lbs (each) of lead shot and put a cover (edges also cork lined) on it.  My BBs now weigh about 105 lbs each!  I took them off of the isolation platforms since they couldn't take the weight anyway.

This sounds metaphorical but the sound now has a more solid bass to it.  Even without the isolation platforms I'm getting strong clean bass with a very hard hit and as much or more separation and detail up and down the scale.

I think my BBs are now closer to Steve's at the base although mine have more mass there.  I don't know what else I could do to these at this point so it's a good thing I'm happy with how they sound.  I researched hardwoods a bit and if I were ever to build another, better looking pair of BBs, I'd likely use 8/4 Hickory and follow more closely Steve's design.  Hickory is the hardest and densest American hardwood.

Here are a few pictures of my shot-box build.

Cork lining:


Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/21/19 at 16:55:45

Box with cut outs for baffle footers:


Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/21/19 at 16:57:44

Box installed and filled with lead shot:


Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/21/19 at 16:57:55

Thanks Archie, this is what I had in mind as well.  I also have not put my handles on yet.  

I think I am going to do everything when I put a finish on the baffles so they will be out of commission for a week or more.  It will give me a chance to put my old OBs back in for comparison purposes.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/21/19 at 16:59:07

Box with cover -- all done:  (linseed oil finish, BTW)


Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/21/19 at 17:02:11

Last night, I played around with the sub and super tweeter.  Some help on both ends.  Overall, the sub impact was bigger than the ST from just what I heard.  Interesting how the ST has an impact below 10Khz.  1/24th octave smoothing.

I don't know what that dip at 40hz is about.  I'll play with phase.


Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/21/19 at 19:41:34

Nice Archie! Much nicer than than the sandbags I plan on using :-[

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/21/19 at 20:28:24

Thanks Geno.  I don't know the exact theory behind the base mass but I get the idea that stiffness might be most important and mass second.  A heavy (stiff) bar across the bottom of your baffles might do more than just sand bags.  The stiffener was something I missed that both Randy and Steve have in their baffles.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/23/19 at 22:13:02

Steve,

Any tips for painting the drivers?  I am more interested in coloring the foam on the front than the back basket.

Also, how do you feel about your figures given for the HP versus torque between the F15 and Crystal 10.  Were those proportions about right?

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/23/19 at 22:55:20

How about a Sharpie?  

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/23/19 at 22:56:45

Thought of that but it can be uneven.  Maybe if you go over it a few times.

Title: Re: Steve's BIG BETSY Project
Post by Bottlehead on 08/24/19 at 00:46:01

Hey Pal,

I've been thinking about doing the same thing. The F15 driver on the Lii Audio website shows a black surround, but when mine came, they had gray surrounds. I'm planning on doing white oak baffles with a walnut stain, so gray doesn't really work for me. I wrote to Lii Audio asking for suggestions, but unsurprisingly, got no answer. I could mount them from the rear, I suppose, like Steve did with the BBJ, so that they don't show, but that really wasn't what I had in mind. I guess if a guy was careful enough with masking, an oil-based spray primer with a flat black paint over it would work, as the surrounds appear to be made out of a paper product. Maybe Steve can chime in with some advice, as I've never tried to paint a cone or a surround. I'm also thinking that a black wizzer cone would suit me better than the white cone, but I'm not sure if that would affect the sound. I don't see how it would, but as I said, I have no experience with it.

Randy

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/24/19 at 00:59:42

I don't think painting the cones would be a good idea at all.  Paint would change the mass and stiffness and therefore the sound.  Or am I misunderstanding?

Title: Re: Steve's BIG BETSY Project
Post by Bottlehead on 08/24/19 at 02:21:19

Hey Archie,

The cone that I'm talking about is the small white one just around the phase plug. But you could be right about changing the mass/stiffness. I suppose everything matters when you get to drivers this precise. Maybe a stain wouldn't alter the sound? Dunno. Probably wouldn't alter the stiffness like paint would, but it probably would add some mass. Decisions, decisions. Aesthetics matter, but sound matters more. Maybe I'll only listen when it's dark, and call it good.  

Randy

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/24/19 at 04:08:10


Quote:
Steve,

Any tips for painting the drivers?  I am more interested in coloring the foam on the front than the back basket.

Also, how do you feel about your figures given for the HP versus torque between the F15 and Crystal 10.  Were those proportions about right?




Now that I am going back and forth using digital playlists floating around hyperspace, I find that the analogy was pretty dead on. With a ZROCK on the Crystal 10, the torque figure goes up.  Still at the track it's the classic big block vs. small block experience.

I find that I listen to the Big Betsy F15 with the ZROCK2 off most of the time. I find that I listen to the Big Betsy Jr. Crystal 10 with the ZROCK2 on most of the time.

The Big Betsy with the F15 and no ZROCK2, has considerably MORE hit and weight than the Big Betsy Jr. with the Crystal 10 and a ZROCK2.

I think between the two we have a nice compromise going, a pretty even handed tradeoff that achieves its original design intent. I find myself flip-flopping between the two. Tonight it's clearly the Big Betsy without a ZROCK2 is my favorite.  That tells me that the Big Betsy Jr. is a worthy adversary and probably just as good but in different ways.

It will be interesting to get peoples impressions during DECFEST2019.  I know one thing...  Randy is going to get tired of hearing people refer to the Betsy baffles as the "baby ones" or the "tiny ones" but will have no issues keeping face throughout the event when the "baby ones" sound big and the cost is small.  

When I first listened to the Big Betsy I felt some panic thinking ahead to what these will do to not only Randy's speakers, but Bob's and all of my own. Sadly for Bob and myself, there is probably no silver lining to that cloud, but for Randy, having the same thing with both the size and price scaled down is going to be very appealing to a lot of people.


As far as painting the drivers... which ones are you referring to?

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/24/19 at 04:18:08



Quote:
Hey Pal,
I've been thinking about doing the same thing. The F15 driver on the Lii Audio website shows a black surround, but when mine came, they had gray surrounds.


I wondered what the hell you were talking about, because I kept thinking "they are black, why would you want to color them?"

Best way is going to be to use an air brush. Acrylic satin black for the paint. You don't want to brush anything on it because it will add mass to the surround.

Spray paint in a can can be used if you're a REAL pro with using spray cans... otherwise it will be far worse than brushing, possibly building up to the point of ruining the sound.  The paint would be Krylon Barbecue Grill high heat paint.

The vast majority of people I've seen operate a spray can will ruin the drivers.  People who paint cars and use the spray can with fan tip in the same way can pull it off.

Another possibility might be water based dye, black of course, but if the dope on the surround is waterproof, and it probably is, this is going to fail big time.

I would think sneaking up on it with an air brush spraying far more air than paint, is a safe secure and controlled method for getting perfect results.


Steve

Title: Re: Steve's BIG BETSY Project
Post by Brian on 08/24/19 at 04:28:27

A stationary store ought to be able to sell you a bottle of India Ink and a small sable brush. I would think ink would add far less mass and stiffness than would any type of paint.

Brian

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/24/19 at 04:44:08

BIG BETSY LISTENING SESSION

So tonight I'm listening to the Big Betsys without a ZROCK2 because it's not really needed with these speakers, only with certain really lifeless recordings from the 60's rock era.

Tonights inspiration comes from Santana, a track called Los Invisibles on the Album Africa Speaks.

I have listened to this track come up many times on all our speakers and the BBJ baffles. Tonight is the only time it sounded right. Tonight it sounds like I'm in Africa at a small outdoor club with a nice tight band. The bass player is really tight.  The music is unmistakingly live because it has the HIT and the big growl that you NEVER hear from your stereo...

Holy crap I'm listening to a 2 watt Zen Triode amplifier... this is impossible!  No EQ, No power, No LP, No Tape, just streaming Santana live into my room.  

Now every other time I've heard this track, I've thought 'yea, boy that's some really good music, but it's too bad the sound is so faded out, and lean because we know what it could sound like. Enter Big Betsy... want to know what something sounds like, turns out it's not headphones, it's Big Betsy Baffles.

This is what is so frustrating and seductive about the hobby. You listen to a Santana CD and it almost sounded good. You invite them to your house and have them play out in the back yard, and it DID sound good.  The Big Betsy Baffles are taking EVERYTHING to this next level. Not sure how it does it either, especially without manipulation or EQ, all you have to do is turn it up to a pleasant room filling volume and WOW.... especially when the bass notes drop and the texture of the bass just dominates the space in such a forcibly undeniable way. Kind of like when an F15 takes a hard straight up turn and your stomach is in your throat. Senses are supercharged.

I should also mention that last night I had a listening appointment!  It ended with one song on the Big Betsy Baffles and the gentleman and his son heard what they came for and left to go home and build a pair. That will be fun to follow up on.

I have been watching people listen to speakers they've never heard before for over 25 years. You could say I do it professionally. I have never seen a pair of speakers get these kinds of consistent and instantaneous reactions, ever.  In fact I can remember countless nights of listening to speakers A and speakers B over and over and over and over and over trying to pick the best one.  So far all four times I've demonstrated the speakers it only took one or two songs and the decision was made.

Steve




Title: Re: Steve's BIG BETSY Project
Post by Bottlehead on 08/24/19 at 06:04:08

Hey Brian,

Thanks for the suggestion. Sounds like a winner - especially since I don't have a paint spray rig.

Randy

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 08/24/19 at 06:15:43



Steve wrote .....


Quote:
It will be interesting to get peoples impressions during DECFEST2019.  I know one thing...  Randy is going to get tired of hearing people refer to the Betsy baffles as the "baby ones" or the "tiny ones" but will have no issues keeping face throughout the event when the "baby ones" sound big and the cost is small.  

When I first listened to the Big Betsy I felt some panic thinking ahead to what these will do to not only Randy's speakers, but Bob's and all of my own. Sadly for Bob and myself, there is probably no silver lining to that cloud, but for Randy, having the same thing with both the size and price scaled down is going to be very appealing to a lot of people.


Hi Steve,

I am really looking forward to hearing your creations in October.
In between building and shipping speakers over the past few days, I have spent several hours listening to music in my "audio he shed" switching back and forth between the Betsy baffles and the new baffles with the Lii F-15 driver.

Truthfully, they are both so good in different ways that it seems like an "embarrassment of riches" to have both of them in the same room .....

As I mentioned in the "Sacrilege" thread in the Betsy Open Baffle forum, I have a "tiny" inexpensive powered subwoofer sitting in the left front corner of the room.
It's so small that it hides behind the left baffle and is not even visible ..... but when I turn it on there is no lack of low bass, and integrating it to the point of making it "seamless" was pretty easy using the crossover and volume controls.

I fully expect that Decware Fest 2019 will result in three things .....

1 - Folks with the DIY spirit and a woodworking shop will be building big baffles.
2 - Decware Audio will have a ready market for whatever you and Bob decide to offer to the public.
3 - I will continue to stay as busy as I want to be offering Betsy baffles and Lii 15 baffles to music lovers who appreciate killer sound at a reasonable price .....

Oh yeah ..... there is a #4 .....
Many orders for Decware Audio 2 watt amplifiers .....

41 days and counting .....

Randy

 

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/24/19 at 08:31:25

It's 2:26 A.M. and I just can't tear myself away from this sound. It is so incredible that literally nothing I have ever heard does what this does.  How does it do it?   I just teased it with a ZROCK2 and almost pissed myself. It can give it a lot more presence than bass if you dial it in right. These speakers have really made my life!  I really can't wait 41 days to let you hear it.  You and Bob are going to need to come early so you can get your sht together before people start to show up! This is going to wreck you. Then you have to recover. Then you have to figure out how to help others through it. I'm not kidding.

Note the time. If anyone during the fest finds themselves listening at this hour, you will realize why I don't get a lot of sleep.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Nixxuz on 08/24/19 at 13:42:41

So I asked in another thread if the F15's were going to measure up to the Dayton PS220-8's I've been using. I guess they do. Let's just hope they are still on sale in a few weeks!

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/24/19 at 18:38:10


Quote:
Maybe I'll only listen when it's dark, and call it good.


My eyes are usually closed when listening these days.   :)

I assume the small cone is where the mids and highs are coming from.  I wouldn't mess with perfection.  Painting the frame is another thing entirely.

Title: Re: Steve's BIG BETSY Project
Post by Dana on 08/24/19 at 19:14:58

Probable should be added to the sacrilege thread...

Magnetic attached grills would be a better solution than painting the driver I would think.  Maybe an inverted gravestone shape that's easily replaceable after a listening session.

Planet 10 offers enabled drivers that are painted with a pattern to enhance the sound.  https://www.planet10-hifi.com/index.html

Altering the driver's moving parts in any way could change the sound by restricting movement just like breaking the driver in changes the sound.





Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/24/19 at 19:23:02

Sorry if I was unclear.  I really only want to paint the grey foam that is on the basket in the front to seal the driver in a rear mount situation.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/24/19 at 20:16:54

Pal, have you considered replacing the foam with black foam?  This stuff looks mass produced.  I think it will peel off.  I was serious about using a Sharpie.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/25/19 at 02:19:30

Pal, sorry I miss understood.  Yea, the gasket and frame is easy.  Just tape it off and use the black Krylon paint.  Mine were gray also.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Brian on 08/25/19 at 04:11:18


Bottlehead,
Ha! I said something useful. I love when that happens.  

Brian

Title: Re: Steve's BIG BETSY Project
Post by Andy P on 08/26/19 at 02:40:41


Quote:
I should also mention that last night I had a listening appointment!  It ended with one song on the Big Betsy Baffles and the gentleman and his son heard what they came for and left to go home and build a pair. That will be fun to follow up on.


Thank you, Steve, for meeting with us on short notice. It was really a blast to meet you and see your "sandbox" It is so exciting to find people who have a passion and go all-in on it!  Thank you for how generous you are with your ideas.

Yes, the sound of the Big Betsys with the Lii Audio 15" driver was a show stopper. I want to hear a lot more of that.  It really brought to my mind an old console cabinet from the 50's or 60's. Just had something to it that I am sure you can only get from a 15" speaker.

I ordered the drivers and am thinking about the wood.

I actually was dreaming about selecting the wood for these last night!

Here are a few questions that I have:

1. How critical is the size of the baffle? If I made it 29 1/2. Is there a way to calculate any of this or is it by feel and testing.  Any way to know what would be the minimum size before the sound would be compromised. I really don't know the science around the open baffle concept.

2.  I was eying an Ikea Gretton table top, beech.  1 1/4 think. any thoughts on this material.

3.  I found bowling alley material, very reasonably priced, I am thinking this would be a great way to go.  42" wide, 2" thick maple.  Is there any reason this would not be awesome? This is my first choice and would get me to working speakers the quickest.

Any input is appreciated. I will post my progress as well.  Thanks


Title: Re: Steve's BIG BETSY Project
Post by dank on 08/26/19 at 13:16:58

Bowling Alley Wood:

I checked some out locally that was on Craigs list.  I was expecting something like what you have pictured.  What it turned out to be had no finish (oil I guess), was being stored outdoors, and had become delaminated so it was nothing more than a bunch of narrow strips.  I came away with the thought that maybe the 42" wide alley isn't glued together at all, but rather "floats".  Don't know if that's right or wrong, but I'd sure check that its glued together solidly, as much as possible.

Dan

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/26/19 at 15:26:31

My advice would be to duplicate Steve's dimensions and general build.  I do think there is play in all factors but you won't be sure which to fudge on and which to not.  Go heavy and dense on the wood.  I'm not sure what beech specs are but I used hard maple (1 1/2") and am satisfied.  However, if I built from scratch I'd use 8/4 hickory.  I still think buying countertop blanks isn't a bad way to go.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/26/19 at 17:14:15

I'd agree with Archie.  Go with what Steve did if you can.  

Although, I am pretty happy with my oak stair tread baffles, I am left wondering what I am giving up.  I hope to understand what I am missing at Decfest and will update the thread.

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/27/19 at 03:31:59

The completed Crystal 10’s. Taking them for a test drive. They are really good right out of the box. I’m starting out using the same supplemental bass that Ive been using with my Lil’ Betsy Alnico’s. Time will tell if I can do without that.

I started out with a hickory colored stain, but with the Birch wood, it just didn’t look good. So I ended up with black. I like the way the driver pops against the black. I also just left the silver lag bolt heads and washers exposed for the same reason.

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/27/19 at 03:33:11

Another photo.

Title: Re: Steve's BIG BETSY Project
Post by Bottlehead on 08/27/19 at 05:44:58

Hey Geno,

Looks good! How thick are your baffles?

Randy

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/27/19 at 12:51:27

Hi Randy. They are 25 x 32 x 1 1/2.  15” wide top and bottom.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/27/19 at 13:56:42

One part of the build that was most difficult for me was cutting the second arc on the baffle.  For the first arc, it was easy to keep everything square because the opposite side of the cut is square.  When you flip it and try to cut the other side, you don't have a square edge to keep your material in place.

Anybody got any tips for people who might want to make these baffles?

I ended up using the arched cutoff portion of the wood.  It didn't quite fit but I wedged them in between the board where my jig was anchored and the material.  They made enough contact to allow a stable cut.

I didn't clamp the baffle for this cut because I didn't want to hit it when I swung my arc with the router/jig.  Maybe you guys had room to do this.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/27/19 at 16:05:53

Although I didn't cut my arcs with a router, I figure that the baffle would need to be attached to a sub table that had the router pivot.  The top and bottom straights could also be used to register the piece.  I did have center lines drawn on my blanks which helped align things.

For me, set up and jig making was 75% of the project.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/27/19 at 16:24:31

I must have swung that arc, measured and re-set my jig about 10 times before I felt confident enough to turn on the router.  

It turned out my fixed jig hole was off slightly which was causing the router blade to not hit the exact same point at the top and bottom of the arc.  But once I got it right, it worked well for all four cuts except what I mentioned in the post above.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 08/27/19 at 17:18:06

Just spitballing here. Could you attach the piece to be cut to another piece of material under it. Find center of your piece to be cut and lay out the center points of the arcs on ether side of the part and swing them from there?
Double sided tape would be your friend there, or mount the pieces together where the driver cutout would be.
I got ideas!

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 08/27/19 at 21:07:51

Now after I have thought about it some more I would also make myself up some bump stops so that the second piece would go right where the first piece was. That would save yourself a lot of time finding center again.
A couple of dowels that you could remove on either the right or left side and one on the Y at the top. Easy peasy.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/27/19 at 21:45:45

Both worth considering Donnie.  I pretty much got lucky that I didn't screw it up.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/28/19 at 01:58:36




After doing the first pair of radius by pairing up a centerline and with no more than spray adhesive to hold down the baffle and pivot board... which btw worked fine on the big betsy because it was so heavy. On this one I felt it start to move, so I thanked the wood shop Gods for not shoving that one up my ass and made the following correction:

On the second baffle, I put down a piece of plywood (instead of foam) and screwed the pivot board to it. Then I used the square hole in the baffle and made a square plug the exact same size and screwed that to the plywood also. That was the ticket. Just drop the baffle onto the square plug and cut. Then flip it over and cut again.

Also looking at this picture it reminds me that this is not the job for a consumer grade plunge router, or plunge router of any type in my opinion. Too much flex in the router base itself to make a clean cut like this.

I got lucky with this vintage PC router, one of the last ones made in the USA before moving the plant to Mexico. The cast base is so rigid that you could shoot it through the hull of a battleship and expect it to be intact. In contrast, the cheap plunge router from Menards started to melt from the profanity the first time I tried to use it. Then it was used by a non-terrestrial (attracted by the profanity) who couldn't resist the opportunity to make it drill a hole through my project and table top. That of course started another round of profanity, so he invited his friends and they all fed off the dark energy until I got wise to it.

I know that was more information about the router than was needed but I learned how to get off topic like that from Bob... and it's completely true.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/28/19 at 02:13:31


Geno,

Love the room, and the tube organization : ). Baffles look good! We'll look forward to your impressions.


upload png



Steve


Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/28/19 at 02:37:01

Thanks, Steve. Although I know I get major points taken away because I did not make the wood baffles myself...

They sound really good already😉

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/28/19 at 02:38:53



Quote:
Thank you, Steve, for meeting with us on short notice. It was really a blast to meet you and see your "sandbox" It is so exciting to find people who have a passion and go all-in on it!  Thank you for how generous you are with your ideas.

Yes, the sound of the Big Betsys with the Lii Audio 15" driver was a show stopper. I want to hear a lot more of that.  It really brought to my mind an old console cabinet from the 50's or 60's. Just had something to it that I am sure you can only get from a 15" speaker.

I ordered the drivers and am thinking about the wood.

I actually was dreaming about selecting the wood for these last night!

Here are a few questions that I have:

1. How critical is the size of the baffle? If I made it 29 1/2. Is there a way to calculate any of this or is it by feel and testing.  Any way to know what would be the minimum size before the sound would be compromised. I really don't know the science around the open baffle concept.

2.  I was eying an Ikea Gretton table top, beech.  1 1/4 think. any thoughts on this material.

3.  I found bowling alley material, very reasonably priced, I am thinking this would be a great way to go.  42" wide, 2" thick maple.  Is there any reason this would not be awesome? This is my first choice and would get me to working speakers the quickest.


Hi Andy,

Make it as close to the original size (or larger) as possible.

Beech is probably a good material, but my gut instinct says the thickness of the baffle is perhaps more influential than the material. I would say regarding material, that the stiffer denser woods are going to bring better high frequency response off the wood itself. And when possible, using two different kinds of wood have a very positive effect in distributing energy throughout the baffle.

The bowling ally material I would think would be awesome but some good points were made about condition. My guess is that it probably is well glued together, but it may not be an exterior grade glue.  I've seen projects made from bowling lanes that were not left outside that felt solid and looked great.

I imagine someone with a large room could find a pair of live edge slabs that were wide enough to make a pair of Big Betsy Baffles, in that case probably 3 inches thick would be ideal.

Another expensive idea is to make a pair in the same fashion as they make live edge river tables by ripping it down the center and flipping the live edges inward and filling the gap with blue tinted resin making it look like a real river running down the center.

Some examples:





There are lots of Youtube videos on making these 'river tables'.

Thanks,

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/28/19 at 02:52:01



Look, I can see a pair of Big Betsys right here.




If you want a Big Betsy think BIG, which is to say stop thinking about how to make it smaller.  Even in Geno's room which was just pictured, the full size baffles will work fabulously.  Ask Pal!
-Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/28/19 at 03:38:44


I am pretty certain you will see this thread explode come DECFEST2019. When people hear the hit, and see that the large size disappears completely, and really takes no more floor space than any other speaker-- things are going to change fast. They are the most fun speaker I've ever heard and get the most music right of any speaker... which is to say that when you stream music looking for tracks that sound good on your system, these speakers will make at minimum 3 times more tracks sound good enough to favorite, than any other speaker.

The F15 drivers from Lii Audio seem to be the closest to the vintage drivers we grew up with in the 1950's and 60's.  That have that tight hit and clean live sound that was completely lost when console stereos were replaced by box speakers with smaller loose power hungry drivers.

If I had these drivers when we were building lots of the full size Jensen Imperial Horn Speakers, I'm sure it would have taken it up another notch, the driver is that good, besting even our favorite vintage stuff from JBL, ALTEC, UTAH, EV, to name a few.

Let me put it to you this way... I'll be ordering another pair of the F15 drivers as emergency spares.  I'd be devastated if one or both were destroyed and couldn't be replaced.  Small insurance policy the way I see it.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/28/19 at 03:47:21



Quote:
Thanks, Steve. Although I know I get major points taken away because I did not make the wood baffles myself...


I disagree. If you don't have a shop, you can't make speakers.  Also sometimes when you do have a shop, you don't have time.  No points taken away.  In fact 3 points added for achieving goal in the quickest manner for the least amount of money.  That's the way I look at it, because that's the way it is.  Also a 5th of a point for making it a full 1.5 inches thick I think is in order : )


Steve

Title: Re: Steve's BIG BETSY Project
Post by 4krow on 08/28/19 at 05:51:00

Steve,

I have found using the right tool for the job makes a completely better experience overall. The worst for me is repairing a tool just so it can be used.

Title: Re: Steve's BIG BETSY Project
Post by Bottlehead on 08/28/19 at 06:11:55

Hey Geno,

Thanks for the info. 1.5" seems to be the magic number. I'm thinking that I would like to scale Randy's standard baffle up 1.5 times for the Alnico driver, with added thickness, and I think that 1.5" will be my target.

And I agree with Steve, no points deducted for finding a way to get it done without a shop/tools. I have a router, and modest woodworking skills, but I probably wouldn't be comfortable taking on this project with either. So I appreciate you and Jeff turning us all on to CraftCuts.
I see myself placing an order with them in the very near future.

Randy

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/28/19 at 13:04:05

Craft Cuts is highly recommended. They did a great job on the baffles. I also had them make 10” x 14” x 2” bases.

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 08/29/19 at 00:05:26



Hi Geno,

What material did you have them make the bases from ?

Thanks,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/29/19 at 01:04:30

Hey Randy,

Birch is the only option they have in wood. The only other option is MDF.
The baffles are 32” tall, which make them a bit top heavy. As is, they don’t try to tip over, but a decent bump would send them over. A heavier base would have been better, but at present I have 3 bricks on each base. That’ll do until I come up with something better. I love Archie’s shot box!

Best,

Geno


Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/29/19 at 01:17:34

Geno, the lead shot comes in nice looking bags if you wanted to just put 25lbs on each base.  They are cloth with a plastic liner.

https://www.cabelas.com/catalog/product.jsp?productId=2314213&categoryId=0&parentCategoryId=0&subCategoryId=0&indexId=0&itemGUID=daba9bb3ac10a8546c213d096658e890&destination=%2Fuser%2Forder_details.cmd%3Fid%3D9kE3wyO2Gb0Z%252FYJlVRHvRg%253D%253D%26key%3D238c0d945fef46ceb1cd9922814b95c7

Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/29/19 at 03:02:57

Thanks Archie! It just so happens that I have a gift certificate from Cabela’s, so that is what I’ll do.

Title: Re: Steve's BIG BETSY Project
Post by Andy P on 08/29/19 at 13:58:15

update on the bowling alley wood.

I looked into these quite a bit and decided to not go that route.  I learned a bit about bowling alley construction through (disclaimer: not scientifically researched and may even be BS) turns out the first section where you throw the ball is event thicker, @3" it then feathers into pine, so a lot of those panels are pine.  Then back to maple at the end (at least that is my understanding).

I was also told that the boards are laid on site much like a wood floor in a house. they have a profile on the edge that accepts the next board and then they are NAILED!  show stopper for any cutting or shaping.  

So while the wood is a great bargain, it may not be much fun to work with,

Also, I am guessing the glue they use is minimal, and that it does not fare well outside where a lot of these panels get stored.  I saw a lot of panels online where the boards were loose. The person I spoke to said, the panels can loosen up and have flex in them.

So while these would make a great tabletop, I am guessing they may not be the greatest to work with. If I ever run across one here in town for cheap, I may experiment with it.

Regarding the thickness.  I am hearing the 2" or even more would be better than the standard 1 1/2" thickness?

I spoke to a lumber mill here in town and they said, to get a 2" finished board, they would have to go up to 2 1/2 nominal thickness and that would greatly increase the price.

I love the idea of the book-matched panels.

Speakers are coming this week.

Great forum!  Thanks for the feedback

Title: Re: Steve's BIG BETSY Project
Post by deucekazoo on 08/29/19 at 14:19:19

Andy P, thanks for the info about the alley wood. I always thought they were solid maple all the way down.

I have been looking at counter tops from Menards. They are solid birch and come in two different widths and a few different lengths. They are also 1.5" thick so if you wanted to go 3" thick, just glue two of them together. But once you go that thick you have to worry about  back cutting the driver so its not in a tunnel and letting it breather. This might be a little more complicated unless you have the correct router bit.
Keep us posted on your build.

Title: Re: Steve's BIG BETSY Project
Post by Showme on 08/29/19 at 15:17:30

I used the Menard's butcher block  countertops, 72"x 36" to make an audio rack. I cut 4 36" x 18" shelves and used all-thread for the uprights. Worked out great. The point in me saying all this is that I agree, their countertops would work great for the baffles I'm sure.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/29/19 at 16:24:34

The Menard's tops look like a decent price.  I've posted a link in a couple of places in this thread where you can get 1 3/4" Hard Maple tops too.  For no other reason than Steve setting the bar with his hard and dense tropical HW baffles at 1 3/4" thick, I'd try to go hard and thick too.

The amount of work that goes into cutting the blanks into baffles far outweighs the "slight" increase in cost of getting the best material possible to start, all within reason, of course.

Title: Re: Steve's BIG BETSY Project
Post by Andy P on 08/29/19 at 19:03:39

Ash glued up panels.

I reached out to a lumber supplier that does table tops in town and they quoted @ $520 for two panels 1 3/4 x 42 x 33. Material is $275, labor is $225 plus tax. It looks like 2 1/4 panels would cost about $50 more total.  Would you suggest going with the 2 1/2 panels?

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/29/19 at 19:19:58

I don’t think you have to go that thick, but if you have the budget it would be interesting to see what you think.  Easy for me to say ;)

I’ve think the group has had luck with 1”, 1.5” and 1.75” so far.  Randy has had good sound with the smaller 3/4” baffles so I don’t know if you can go too far wrong.

With my baffles at only 1” I have been glued to them for the last two weeks or so.  I haven’t pulled them out of the rig to finish them because I don’t want to be without them.


Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 08/29/19 at 20:15:31



Geno wrote .....


Quote:
Birch is the only option they have in wood. The only other option is MDF.


Geno,

Is that birch plywood (specifically Baltic birch) ?
If so, I am presuming that they don't offer any hardwoods ?

Thanks,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Geno on 08/29/19 at 22:49:28

That's correct, Randy. Baltic Birch plywood and no hardwood, unfortunately.  

Best,

Geno

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/30/19 at 03:23:42

Well last night I switched over from the Big Betsy to the BBJ and this time placed the BBJ on the outside edges of the Big Betsy which means very wide apart and probably only a foot or two from the side walls.



This is btw working very well. I was frankly a little surprised, but most of what I place wide like that works in this room. I know I listened to the DNA2 in the same location many many times.

Anyway, I turned on the ZROCK2 and set it where it needs to be and thought I should give these speakers some more time... the Big Betsy are so damn good that like Pal said, you hate to turn them off, but I did and now have the intension to see if I can like the BBJ as much or more. This is how it works, cycle and repeat, cycle and repeat. That way you slowly take the ego and subjective aspects out of the analyses and become more objective.

So far it is going very well. No doubt the BBJ sounds more real in the top end. However with the ZROCK2 in place and this current set up I am getting a more than respectable frequency balance, very similar to the Big Betsy.  In fact last night I gave it the real acid test, which is the hungry hippo track (I call it) that set the bar for low bass response last year on the Imperial Folded Horns built into the West end of the listening room.

I have to say it handled that better than it had any business doing it that's for sure!  In fact it went off without a hitch, sounded full and deep. About half way through or so when it really drops, I was again surprised at what I heard.  During the track I thought I was hearing the low end roll off point and then that part came on and it dropped at least nearly an octave. At that point I am pretty sure that with the ZROCK2 the BBJ using the 30Hz Crystal 10 driver actually dropped lower than the Big Betsy and sounding completely together, no breakup. Very impressive and somewhat unexpected.

Naturally I'll have to measure these things one of these evenings and see what happens. I have some unique measuring techniques that will no doubt be very helpful when you want to connect the dots between frequency response and what you actually hear in your room. If we lived in a world where software didn't just stop working one day because it needs updated and things weren't so F'in complicated... my prior attempt to capture a screen video of me doing just that wouldn't have failed. Even got pissed and purchased different software that also didn't work.

Truthfully, the F15 is more visceral in the low end, and the Crystal 10 slightly softer in the bottom, but isn't everything after hearing a Big Betsy? The answer is yes.  Other than that the Crystal 10 pretty much sounds more realistic.  

Additional evaluation of the Crystal 10 will eventually have to take place in it's ideal 220 liter cabinet at which point a lot of things could change. It will probably be the ultimate shoot-out in the end.

Steve




Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/30/19 at 05:15:52


As the evening progresses and the experimentation continues, I am playing a Qobuz playlist of Acoustic Sole which is pretty Jamaica bass heavy man. It didn't take long to turn off the ZROCK2 which took the otherwise bloated presentation and made it tight and clean as a brick. That was nice.

Can't do that with a normal loudspeaker if you keep in mind that the BBJ requires and would come with a ZROCK2 which means that the speaker has an active component that is fully adjustable and defeatable for the ultimate in adjustability on the fly as you listen. It is easily handing a super wide range of music from disco to classical with real finesse.

The fact that the speakers can sound this good without a ZROCK2 or anything else is what is so encouraging about it. You are using the ZROCK2 almost more for recording compensation than for speaker performance.

The test is while you listen and get lost in writing a forum post, how many times do you actually forget the ZROCK2 isn't ON.  Right now with all these mixes I wouldn't want it on, or at least not adjusted nearly as far as normal. I like this ability to drill into the recording and dial it in the way it was obviously intended to be heard, the way it sounds best... This takes riding the gain to well, it's like adding a multiplier.  

Right now for example, with the ZROCK2 bypassed, the music is perfect. On the Big Betsy there would be a nagging emphasis on the HIT and weight of the recording which is no doubt recorded with a fair amount of compression. They would just be telling you the truth. The BBJ on the other hand lets you ignore this reality and dial it into however it needs to be to sound good.

You might ask, why can't a ZROCK2 on any pair of speakers do that and the answer is that to do it THIS well you need speakers that are by default dry and accurate so that when you add weight you don't get mud. Or put another way, when you listen to a recording that is gained up with bass heavy music and a lot of compression, if you speakers have good bass you will want to put an ice pick into your forehead to end the boom... the leaner speaker can thin this out and get it literally just perfect considering what it had to work with.

This is a big plus to this BBJ approach that I am starting to appreciate.

See, now I put on a Ben Webster 24 bit recording and got 1:51 into the track before I remembered that the ZROCK2 is still off.  Now I'm trying to decide if I care....   oh the curiosity....  what the hell, ... OMG sounds so real now.  Seriously.  It sounds real.


Steve

Title: Re: Steve's BIG BETSY Project
Post by Brian on 08/30/19 at 05:38:09

Steve said:  "No doubt the BBJ sounds more real in the top end."

Hi Steve,
I know you like the purity of no crossover, but how would it sound if you added a bullet tweeter to the 15 inch with only a capacitor?

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/30/19 at 05:57:07


Similar but diss-jointed.  It would sound better to do the opposite of a ZROCK2 and give it a slight treble boost in the signal path in my estimation.

It may not even be the top end extension that is making the Crystal 10 sound more real in the top end, it could be the cone material and frequencies around 2K~8K and how they are presented, which I suspect is the actual case.

We all have to admit despite the "feeling the 40K frequencies" camp, that most of us couldn't hear past 17K to save our own life.  Also, most peoples perception of "highs" lives in the 5~8K region and their perception of lows lives in the 120-40Hz region.  The top and bottom octave are almost never heard nor reproduced in live situations  unless you are far away to hear the low and up close within feet to hear the highs.  

The Big Betsy is a lesson in bass.  You thought it was about how low it went, but you found it was about how big it got.  It is a real genuine lesson in bass perception.  Should be donated to science.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/30/19 at 06:41:50


Here is a great example:  Rua JoAo Pereira da Rosa on Volupias by Gariel Ferrandini

This album is like setting inches away from the reed and a lesson in textures. This particular track just wrecked me on the BBJ/ZROCK2 combo...  it was simply just over the top. It was WAY MORE intrusive than Big Betsy, so REAL to be almost disturbing if it wasn't so pleasantly real and basically pleasant. God I can imagine dark music presented in the same resolution would be permanently damaging. The Tibetan bowl near the end is spot on... just one of the most real things I've heard. Now... if I play this again on the BIG BESTY it will drop 2 points. Regular speakers that we have another 2 points. Hi-Fi speakers with large crossover and low efficiency, another 4 points.  

You know it seems each time I cycle back to the BBJ speakers they are better. When you hear them on real recordings like this, your mind will bend. Please don't be operating heavy machinery or planning to mow or drive. Just hold yourself up and try to keep you chin from scraping the floor.

Boy, this is really going to blow some peoples minds this year at DECFEST! Nothing has ever been presented at DECFEST since the first fest after the 911 attack that does what this Anniversary System does on the BBJ or Big Betsy speaker 100dB systems. I can hardly wait. There is really nothing like creating something that is good and then blabbering on about it in public knowing that everyone will hear it first hand in October and find out (as usual) it wasn't hyperbole...

...Then to see the thrill in everyones eyes as they realize this is obtainable and that they can make it happen too!

I did not know even a year ago that this sound was even possible  with only 2 watts and especially on so many affordable levels. By that I mean that even broke, you can walk away with 65~75% of this sound for less than $500 with a pair of the original Betsy Baffles.

I guess if this is what it takes to get people not yet taking that original design seriously, then this is what it takes. ; ) I know if I went to this years fest and listened to the Big Betsy, and the BBJ and then finally the original Betsy that was less than 1/10th the price and really IS 65% of the sound OR MORE, and just about as big, I would be thrilled as shit.  In fact I would suggest Randy have a few pair with him when he comes just to give a couple attendees the thrill of spontaneous combustion as they drive home with a pair!




Steve

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/30/19 at 16:07:53

Steve, what's your impression of the Big Betsy with the ZROCK2?  I'm sure you've tried it.   ;)

I find the bottom to be overpowering at times with this combo.  Not bloated or muddy but just, maybe too big.  I love the mid range boost the ZR2 gives sometimes even more than the bass boost.  I think you're on to something when you suggest a ZROCK for the highs.

My hearing goes out between 14kHz and 15kHz and I never find the BBs lacking in high end sweetness.

Title: Re: Steve's BIG BETSY Project
Post by Lon on 08/30/19 at 16:47:35

If you look or search within the thread you will see that Steve has commented on the ZROCK2 with the Big Betsys. . . .

Title: Re: Steve's BIG BETSY Project
Post by ZZuZZaXX on 08/30/19 at 17:23:10

I don't mean to hijack this post but I have a ZORCK question.  I recently acquired an older set of Klipsh Forte loudspeakers.  How does a ZORCK work with a speaker with extensive low to start.  I'm hoping the ZORCK can sweeten the mids and highs.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/30/19 at 18:07:31

I've scanned back a bit and in Steve's post #490, he had this to say:  
Quote:
With regard to the differences between the two and how the ZROCK2 plays into it...

The Crystal 10 in the smaller baffle with a ZROCK2 sounds similar to the Big Betsy without a ZROCK2, as predicted by the difference in baffle size and QTS differences in the drivers.


I remember posts where he explained why he doesn't use the ZR2 generally (e.g., #304) and I haven't found where he tried and evaluated it with the BBs.

I think I may be the only one using it with BBs.  I could live without it only if I'd never heard what it does to the BBs (and other speakers I've had it in front of).

ZZ..., The ZR2 boosts the lows that are rolled off in most recordings.  My HR1s have excellent low end capability but it took the ZR2 to make them shine.  I find a sweetening and thickening of the low-mids (female vocal range) but nothing in the highs.  By contrast, the F15s roll off fairly strongly below 50Hz, so in my room I find the ZR2 necessary to compensate for both the drivers and the music.  (subject to my comment above)

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/30/19 at 18:51:55

Archie,

I use the ZROCK2 with the Big Betsy as well but it's source/recording dependent.  Often it's barely on or bypassed with the Big Betsy/F15 combo. If a recording can benefit from a sweeter midrange I'll have it barely on. ; )  But keep in mind this is with the CSP325 preamp.  Without the preamp, the ZROCK2 would likely be left on 90% of the time and turned up a bit higher.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/30/19 at 22:55:06

I have the anniversary modified CSP3 in front of my ZR2 and although I've turned it down some, I still prefer it to not.  And when it's too much, I'm generally too lazy to get up and adjust it.  Now, if there was ever a component in need of a remote!   :D

I do generally find it too much with newer music, the kind that has the driving bass beat.  Must be electronic "drum" or something.

Title: Re: Steve's BIG BETSY Project
Post by Lon on 08/30/19 at 23:54:19

It's mostly the mastering, most new music is mastered so "loud" that there is no "breathing room" in the music and the ZROCK likes to fill in the breathing room. . . . That's how it seems to me.

Title: Re: Steve's BIG BETSY Project
Post by johnnycopy on 08/31/19 at 01:56:13

As a former regular of hawthorne audio forum, open baffles have been in my life for 10 years

I have Trios, which consist of two 15 inch open baffle bass drivers one below and one above the 15 inch sterling midrange driver (with a 10 pound concentrically mounted compression tweeter).  Now midrange is a strange name for this driver cause it can play fantastically well without bass augmentation, but that was its designation.

Randy knows the hawthorne trio baffle layout and perhaps randy also had the 15 inch mids though not sure if his were the standard or sterling range

Steve, The Back and forth discussion you are sharing between the 10 and 15 inch drivers on the open baffle remind me of what darrel hawthorne talked often about after he worked to design his own 10 inch midrange driver.

He ended up preferring the 15 for larger scale, rock, synth music, with the 10 best on more closely miked, acoustic, vocal stuff.

It would have been interesting to have tried your zrock on those10’s.

for a change of pace i also bought a set of betsys. I built crude plywood square open baffles which can stand alone, or can be inserted directly into my trio baffles (replacing the hawthorne 15 inch mid compression tweeter) so i can hear the betsys on one baffle surrounded abive and below by the 2 15 inch bass augmenters.

There certainly is music i prefer with the betsys, but s larger portion of my music is more enjoyable with my trios.

Along with the msin speakers, i have four subs i can bring in and sdjust depending on configuration.

To be fair i have not heard the effects of your zrock which may have helped the hawthorne 10 inch drivers and certainly could help the betsy up to her limits.

I do run out if steam on the betsys though as they just can't do some of the types of music i listen to at the levels i enjoy.  Kraftwerk radioacivity from the mix album needs volume!!

I am really enjoying listening to you and all contributors on this thread and appreciate your willingness to continue to experiment and to improve your products.

I have had your amps and older versions of your fostex speakers and thoroughly enjoyed them all.

Keep up the good work, and i will be reading and watching with great interest!


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/31/19 at 03:35:16

John,

I appreciate the kind words, and wisdom.  The track has Big Betsy written all over it.  Fun stuff!

Steve

Title: Re: Steve's BIG BETSY Project
Post by Brian on 08/31/19 at 04:42:02

I thank you, Steve for the lesson.  
I listened to some of that Rua JoAo Pereira da Rosa - Volupias music on my $30 computer speakers, and I see what you are talking about. A very vivid recording! It must be unsettling on high fidelity equipment!

Brian

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 08/31/19 at 04:51:19




I just noticed that the shadows of the Big Betsy speakers on the carpet are creating a perfect arc.  Not only that, but the exact 10 foot arc the speakers are placed on relative to the listening chair... how ZEN is that? It's an unmistakable sign from the Audio Gods.  See how they work!



Steve

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/31/19 at 16:30:01

Don't those tubular bells start to resonate when music is playing?  That's got to influence the overall sound.  Seriously, maybe I need some of those.

Title: Re: Steve's BIG BETSY Project
Post by bokat57 on 08/31/19 at 18:34:58

How are these BIG BETSY w/ 15" driver in the near field ? I am about 7-8 feet from the speakers.

Thanks
Bob

Title: Re: Steve's BIG BETSY Project
Post by dank on 08/31/19 at 18:42:19

Moved my OB's a couple days ago and saw that my bases weren't as rigid as they should be.  Added some braces that really stiffened things up.  They also act as vertical stiffeners for the OB.



Then I built a couple of dust covers, being they are in my workshop I feel I need to cover them.




Here's the pair:




The speakers are quite bright.  This can be very good, but can also be dangerous in that it opens the door to setting them too harsh via volume and/or certain music.  I'll be quite interested in how Steve's compare to mine and what the Zrock2 does come this October (which is getting closer every day).


Dan

Title: Re: Steve's BIG BETSY Project
Post by lazb on 08/31/19 at 19:44:56

how about covering/protecting the back side, Dan?

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/31/19 at 20:46:45

I wouldn't say good or bad near field but I find I sit as far from them as I can when I really want to listen.  I think 7 or 8 feet would be fine.  The size of the room might be a consideration.  

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 08/31/19 at 21:06:50

I think mine sound fine nearfield.  I would guess mine at 7.5’ apart and that about the same distance to my ears.   Completely disappear.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 08/31/19 at 22:58:54

Dank, did you notice any change in sound after you put the stiffeners on?

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/01/19 at 00:37:52



Quote:
Don't those tubular bells start to resonate when music is playing? That's got to influence the overall sound. Seriously, maybe I need some of those.


Yes, those large chimes will start playing themselves when you listen to music.  This is why I had to make leather dampers for each one. They are split in the back with a magnetic seam.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/01/19 at 02:08:30


Quote:
Steve ..... many thanks for the kind words concerning the Betsy baffles.
However, I usually chalk up any modest success I have had in my speaker building projects to the proverbial "blind squirrel finding an occasional acorn" .....




Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/01/19 at 02:24:43




The Corner Horns behind your baffles make kick ass bass traps if you short the voice coils with a jumper wire.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/01/19 at 04:24:33


Boy I love Apple almost as much as Microsoft...

I'm setting in front of a bad ass video editing / creating machine that I've used to create basically all the videos on this web site, and now with some more forced upgrades nothing is working right.  

I just made a great video and the damn sound has ticks in it.  If we ALL had one hour of our life back for every hour of life wasted in front of a computer that was almost but not quite working right or melting down in front of your face, we would all have another 20 years.  Someone has to pay for this.

Anyway, we'll have to do this the old fashioned way.  I'll tell you about the unedited video clip, and you watch it.


Let me do it in the next post.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/01/19 at 04:35:28


SO, I've been wanting to show all of you how I measure loudspeakers in a way that makes sense to the way our mind works, as opposed to an engineer with two pocket protectors and 41 pens. This came about during the process of measuring the Big Betsy and BBJ open baffle speakers. Of course first I measure the speaker with a gated response and then measure the speaker in room from the listening position which is to say measuring the room and the speaker and then look at it and compare it with other speakers measured in the same space and waste hours learning nothing.  

Sure you can identify some room/speaker issues and work on them, but I'm talking about looking at a frequency response chart, like the two Dank posted earlier and realizing that they tell you virtually nothing. Just some feel good graphs to publish with no clue what the speaker sounds like.

Myself, I don't care what the speaker sound sounds like, I am in a room where a loudspeaker is placed and therefor a part of. I want to see on a graph what I am hearing, and I want to see it in real time, and in a way that makes sense with concrete numbers I can work from. I want to see what music measures like in my room, not impulse response or pink noise or frequency sweeps.

This is how I do that while listening to music.... and measuring loudspeakers while I am listening to them.
Just watch the video and study the peak notes which are tracked, and you will see what frequencies are responsible for the sounds you hear.

https://decware.wistia.com/medias/bcsykv14ky

When I am really trying to digest something sometimes I will record it with this device, and then play it back over and over as I watch it.  I'm pretty sure I have more hours staring at this real time graphic as I listen than I would care to admit over the past many years. Easily 100's of hours. You speculate where you think sounds live and you are wrong. You think you need response to 40K and < 20Hz, you are wrong. What you need is the correct tilt for a given room, which is perfectly illustrated in this video. See, high frequencies operate by different rules than low frequencies therefor to the human ear, they need not be as loud and should not be as loud.  

For those of you who are watching the video multiple times, you might notice that near the end of the video the lowest note you hear drops way deep yet the graph reads around 60+ Hz or so...

Let me say it again.

The loudest, lowest note in the video by the graph measures over 60Hz despite being obviously lower sounding than the 49Hz we see reoccurring throughout the video.

What this is telling you is that the low bass note is a seed, and the harmonic is the amplifier that determines how mean and how loud the seed will sound. My guess is that the low note we hear is probably 32Hz but because it is perhaps 6db or more lower in amplitude than the over 60Hz harmonic, we don't see it on the graph.

But, when we look at a speakers frequency response we assume that if we want to hear 32Hz sound as loud as 60Hz, the line must be flat between those two points which is to say the -3B point must be well below 32 Hz. How easily fooled we are, and how little we actually know.


Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/01/19 at 05:34:25


Dank, nice upgrade for sure, on both counts!  BTW, that cool fixed biased zen amp you built a while back... have you hooked that to your Big Betsy speakers yet? You really don't want a solid state amp on a .7 QTS speaker unless is has little or no feedback...  hang a damn triode on it man and report back.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/01/19 at 05:42:24



Quote:
Steve ..... many thanks for the kind words concerning the Betsy baffles.
However, I usually chalk up any modest success I have had in my speaker building projects to the proverbial "blind squirrel finding an occasional acorn" .....


Or there's this...



Hehehe...

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/02/19 at 04:24:35


Quote:
Boy I love Apple almost as much as Microsoft...

I'm setting in front of a bad ass video editing / creating machine that I've used to create basically all the videos on this web site, and now with some more forced upgrades nothing is working right.  

I just made a great video and the damn sound has ticks in it.  If we ALL had one hour of our life back for every hour of life wasted in front of a computer that was almost but not quite working right or melting down in front of your face, we would all have another 20 years.  Someone has to pay for this.

Anyway, we'll have to do this the old fashioned way.  I'll tell you about the unedited video clip, and you watch it.


Let me do it in the next post.

Steve


Wow, quoting myself... hmmm.  Well I found the problem.  IMOVIE doesn't like the sound file format in MP4 imported videos. Change the videos to MOV and then import them and no problem.  Well almost, the sound comes out perfect, but now the video is trashed.  You get to cut the sound from the video and stitch them back together.  Isn't that exiting.  He Bill Gates, instead of going to dinner tonight with friends, why not cut and past and stitch together some audio and video files while researching why this damn crap doesn't work?!?! Classic example of we have a problem here Scottie, and a decision was made to not do anything about it, and not say anything about it knowing an incompatibility with MP4 will cost the company more than pissed off people who don't know exactly what to blame the problem on.  Good job Apple. Or from perhaps their point of view good job Microsoft for making more crap.

So anyway, I have the video done now, so we no longer have to do it the old fashioned way...

-Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/02/19 at 04:51:04

We just have to wait 51 minutes for the video to upload...

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/02/19 at 06:20:04


51 minutes my ass....  and really, how hard is it to calculate the size of a file and the the bite rate of the transfer to predict how long it will take?
Funny how in the 1980's we never had any issues with getting it within a minute or two, and that was at 300bps for Christ sake.  Now you have 10MBPS and we can't really narrow it down by +/- 50%....  you know with all the background tasks going on and the perpetual data harvesting who the hell knows how long anything will take. What a cluster F. I hope whoever was in charge of this gets the stale McDonalds breakfast sandwich I had to eat this morning ; )

A little dark humor to brighten your day : )

Steve

OMG... it literally says "uploading 53% - 49 minutes remaining" !!!  I give up.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/02/19 at 07:15:11

Woohoo it's only 1:14 A.M. !!!  The video is finally uploaded and transcoded for your viewing pleasure...





Steve

Title: Re: Steve's BIG BETSY Project
Post by Ellsworth on 09/02/19 at 16:53:47

I have been following this thread with great interest and am very intrigued.  I am eager to jump into the OB waters but want to do a sanity check first.  As a point of reference, my 25th Anniversary UFO is feeding Omego Super Alnico monitors supplemented by ribbon supertweeters and an Omega Deep 8 sub.

My challenge in trying open baffle is that I can't have the speakers on the floor and need to create OB speakers that sit on top of the stands that the Omegas sit on.  This has me concerned that if I use 8 inch drivers,  bass will be severely lacking even with the subwoofer support  

To try to emulate the Betsy look, I am thinking of creating wings on hinges to allow for a squared front that then opens into something resembling the Betsy shape.  With that design, they would look similar and have the same visual footprint as the Omega monitors when they are not in use.

All of this is necessary because my living room is my listening room and I can only get away with so much.   Does this approach have a glaring problem that I am missing?

Thanks for any input.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/02/19 at 17:23:37

It is amazing to see where most of the music lives.

Title: Re: Steve's BIG BETSY Project
Post by Brian on 09/03/19 at 05:09:40

I thank you, Steve for the educational video. I think if I had a most musical system that only played from 60 Hz to about 8KHz, and were offered frequency extension at the trade of musical quality, I would not accept the trade.  

Brian

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/03/19 at 12:12:52

Ells,

I am not sure you will get the full Betsy experience with wings.  While they will help with bass production, I don’t think you’ll get the full “baffle as a transducer” effect. Also I would worry about vibration at the hinge.  I have used “piano hinges” in the past to minimize this but was using much smaller drivers.

Title: Re: Steve's BIG BETSY Project
Post by Geno on 09/03/19 at 15:06:13

Ellsw,

Why do you have to have them on stands? Can't they sit where the stands are? The driver will work better, from a bass standpoint, closer to the floor.

And the biggest thing with open baffle is to get them about 3 ft. from the wall behind.

Title: Re: Steve's BIG BETSY Project
Post by Ellsworth on 09/03/19 at 23:13:00

Thanks for the comments.  The biggest reason that I need them on the stands is that my speaker stands are up against a bench/stereo rack that is 18” tall and runs across the entire wall.  It is an unusual setup but it allows me to get the monitor  speakers 2.5 feet from the wall.  

I could conceivably create a baffle that extends to the floor but has the driver located above the bench/rack about 3 feet from the wall.  The bottom of the baffle would be about 1 foot in front of the stereo rack but at least the driver would have room to breath.

Assuming that the wife approves of the look would that be a more reasonable approach?  

Thanks again for the comments.  This forum has always been a great wealth of knowledge.


Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/04/19 at 01:51:38

Ells, I've tried my BBs pretty much up against a wall (they have a minimum 12+ inch gap due to the rear support) and they still sound great.  Plus, your rack behind won't act like a solid flat wall.  I don't know if it would help or hurt since I'm too new to open baffle speakers to have a handle on what the rear wave does.  If you build a pair of these I think you'll be so blown away that you'll come up with a compromise with the wife!   ;)

Title: Re: Steve's BIG BETSY Project
Post by Ellsworth on 09/04/19 at 02:49:42

The only thing I have to lose  is time and a little money (depending on the drivers purchased).  Everything that I read about open baffle sou d describ3s the qualities I look for in music so it will be worth a try.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/04/19 at 03:37:23


If you enjoy building things yourself, this is a great way to go.  If not, Randy's Betsy Baffles for around $500 are a great way to find out what it is all about!

Steve

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/04/19 at 18:40:17

I response to Brian's question regarding a bullet tweeter in post 660 and Steve's response in 661, I have a "super tweeter" and can run it easily.   I also have subwoofers available by just flipping a couple switches.  They are pretty tight (after I got the phase on both dialed in) and don't sound bloated at all.

But with the Big Betsy's I never find myself saying "I need to turn on that super tweeter" and I rarely find myself saying "I wish I had the subs on" for a particular track.

In fact, a many tracks I have listened to with the subs on, I have found myself asking "what are they even adding to this track?"

But like Steve said, the Big Betsy is a lesson in bass - bass that matters.  I also believe it to be a lesson in what really matters in music as Steve's video suggests and most of it is in the middle.  I think that's the reason some speaker designers start there and then work their way out - accepting compromises at either end.

Also, earlier I reported on a particular track that made my 1" Oak baffles produce a dissonant tone.  Last night, I finally put on my handles and tried that track again.  It was gone.  So I guess the lesson here is to follow the formula as close as you can because it all matters.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/05/19 at 00:34:59


Quote:
So I guess the lesson here is to follow the formula as close as you can because it all matters.


Intuition is a wonderful thing.  Thank you Steve!   [smiley=thumbsup.gif]

Title: Re: Steve's BIG BETSY Project
Post by Ellsworth on 09/05/19 at 00:41:49

Thanks for the encouraging words.  This will be my Winter project.  It is interesting to hear that the super tweeters don’t make much of an impact.  They are a big help with my Omega Super Alnicos.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/05/19 at 03:26:44


Quote:
Also, earlier I reported on a particular track that made my 1" Oak baffles produce a dissonant tone. Last night, I finally put on my handles and tried that track again. It was gone. So I guess the lesson here is to follow the formula as close as you can because it all matters.


It's that kind of crap that makes you believe in the Audio Gods... I mean seriously. I still remember the first time I removed the handle on an original Betsy baffle and immediately put it right back on. The strength in fragility is a demonstration of supreme intelligence of which I'm sorry, we're just not quite there yet. Making or breaking the sound of a speaker by a simple handle in the exact right place is their way of signing their work. They knew it would be discovered.

Steve   ;)

Title: Re: Steve's BIG BETSY Project
Post by Brian on 09/05/19 at 04:24:04

I thank you, Palomino for your answer to my Tweeter question.
Brian

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/05/19 at 15:00:39

Hi Brian,

I do perceive benefits to the ST in my other build but as I said, not with the BBs.  It could be I have a sensitivity match issue with the F15s being more sensitive, but in my other build I have to use a resistor to take them down a bit or they can be overwhelming.  With the F15, I ran them wide open and maybe that was still not enough to feel the effects.

The Big Betsy's sound stage is so huge and the drivers produce such tight, focused music, I'm still of the opinion that a ST is not needed.

Part of my somewhat impulsive jump to the Big Betsy's was a desire to simplify and while the build was a bit challenging, they are a stupid simple way to get great sound - especially with a 2 watt SET.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/05/19 at 17:39:15

Pal, did you ever stiffen the bottom of your baffles?  I remember that, at least originally, you had just two parallel footers coming off of the back.  Given that the handle makes such a difference at the top ...

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/05/19 at 17:49:12

Not yet Arch.

I have some new bass drivers coming in for my other baffles that I ordered a Looooong time ago.  When those arrive, I am going to swap out speakers, disassemble the Big Betsy's - do the base, paint the handles, oil them, wax etc.

Title: Re: Steve's BIG BETSY Project
Post by Brian on 09/06/19 at 03:52:35

Palomino said:  
"The Big Betsy's sound stage is so huge and the drivers produce such tight, focused music, I'm still of the opinion that a ST is not needed."

These are the most exciting speaker to come along in a long time. They seem to be the most perfect speaker to have come through the Decware collection.  

Brian

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/06/19 at 05:32:14


That is absolutely true.  Never before has a 2 watt Zen Triode Amplifier been able to run you over like a monster truck using such a small speaker.  Usually it takes a 28 CUBIC FOOT FOLDED HORN on each channel to accomplish that and with the right vintage high efficiency drivers.

We have never had anything this good...  the F15 driver is similar to the vintage drivers of the 1950's, you know, like that magic bullet that you could never hope to find in perfect condition and even if you could, you could never share it with anyone because there would only be one pair available.  These drivers are GAME CHANGERS for low power tube gear.  Many audiophiles use them in larger ported cabinets, but I can promise you the Big Betsy will have them re-thinking that move.

This is what will make this years DECFEST so exciting.  The main focus being the 25th anniversary Zen Triode Amplifier and matching preamp driving a single pair of voice coils with no subs and only 2 watts per channel.  The Harmon Kardon receivers we grew up paired to Altec Lansings didn't hit like this... well they did, but it was dirty by comparison.  It's a real thrill to find a speaker that will CRUSH everything you have and do it on our favorite amplifier, the Zen Triode 2 watt SET.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/07/19 at 04:06:08


UPDATE LISTENING COMPARISONS

So for the past week I have been enjoying the Big Betsy / F15 combo and largely without the ZROCK2. With my system, I just don't need it except on occasion to fix bad recordings. The first couple days I wondered how long it would take to miss the Big Betsy Jr.s with the Crystal 10 drivers or if I ever would. Now around a week later I found myself missing them. Kind of craving that faster midrange and extended top end. Actually the tone is better because with those you largely do use the ZROCK2 which is a tone tool. It sounds so good with speakers like this that the combination is every bit as good as the Big Betsy which if you'll remember I wondered if it would be when this all started.  I think each speaker is equally good but with different strengths.  If the goal was to get as good or better Big Betsy sound from a more manageable size then this has been a complete success.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Geno on 09/07/19 at 18:13:00

I have just finished up the Crystal 10’s. A tip of the hat to Archie for his suggestion of a box for steel shot pellets. I got extra bags so I could split the shot into 2 bags so it would fit in the box better. Below, I’ve included some photos.

I’m a few weeks in with Listening to them. So far, so good. I finally stopped using supplemental bass because it kind of muddied the overall sound. Overall, so far, I can see that Steve is prolly right about a Zrock helping with the bass. Also, as good as it sounds, I can’t help but wonder how the bass would sound in a proper cabinet. As Steve said, these really were not meant for open baffle use. With that said, though, they are damn good open baffle!  And I do still have a few weeks until they are broken in good. At that point, I will do some comparisons between them and the Betsy Alnico’s with supplemental bass. That will be interesting, as the Betsy’s May well be, as Steve stated, the best open baffle design that exists. I know it is my benchmark...

*It should be noted that my baffles are about 3” smaller than Steve’s and also are made from Baltic Birch plywood instead of the dense hardwood that Steve’s are made of, so apples to oranges in comparison.

Title: Re: Steve's BIG BETSY Project
Post by Geno on 09/07/19 at 18:14:24

With top.

Title: Re: Steve's BIG BETSY Project
Post by Geno on 09/07/19 at 18:15:27

Front.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/07/19 at 19:40:18

Geno, nice job!  Do you have a ZROCK2 on order?  Did you hear much difference with the shot?

Title: Re: Steve's BIG BETSY Project
Post by Geno on 09/07/19 at 20:30:22

Thanks Archie. No, I don’t have a Zrock on order. When I first got my Betsy setup about a year ago, I had had a Zrock with my previous speakers, but didn’t feel like I needed it with the supplemental bass I had with the Betsy’s, so, like a fool, I sold it.

I think the shot has tightened the bass up. Thank you for the great idea!

On down the road, if I’m not satisfied with the Crystals in my Baffles, then I’ll have a bigger hole cut and try the 15’s 😉

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/09/19 at 01:26:16

The difference between using the Crystal 10 in an open baffle with a sub vs. ZROCK2, is that the later is going to develop a lot of midrange tone similar to a cabinet making the Crystal 10 sound full bodied and warm on it's own. In my BBJ baffle the bass is wonderful sounding.  I have yet to hear it with additional bass augmentation from a sub, and don't really foresee it...

The truth is as long I hear a full amount of bass in the music and I can feel it, I don't really care how low it goes until my objective becomes to hear how low my stereo can get with organ music, etc. Nope, it's about how much of it there is, how well it integrates with the midrange and top end, and how big it sounds, NOT how low it goes.  This is the lesson of the Big Betsy loudspeakers that you will all be learning at DECFEST2019 this year.  I have learned it and now so can you.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/09/19 at 01:34:03


The other day when I was measuring things, I did a comparison between the Big Betsy Baffles and the Big Betsy Jr. Baffles and even though it tells you relatively little, here is is.  The Big Betsy/F15 combo in red and the ZROCKED BBJ/Crystal 10 combo in green.

Measured from the listening position in my room.



You'll have to scroll left to right to read it all.

Steve


Title: Re: Steve's BIG BETSY Project
Post by Radarek on 09/09/19 at 02:11:15

Hello Everyone

This is my first post. Been reading this forum for a while, but now is a finally a time to come in and introduce myself. Lots of great information and tons of knowledge all across this forum. Decware products are on the top of my shop list and right moment is coming soon.

Some time ago I have come a cross Altec 604 e drivers with orginal crossovers.  Since then crossovers were rebuild with new components. I like a lot Big Betsy project and F15 driver been 15" same as 604 in size. I was thinking about building it to accommodate my drivers. Steve, from you previous experience with speakers would this design be a good match for altecs drivers?
Sorry for hijacking this tread a bit.

Best regards

Dariusz Pawlowski aka radarek :)

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/09/19 at 19:45:14

Hi Radarek,

Welcome to the family.

The 604e drivers have a really low QTS in the 20's... meaning they will have poor base performance in an open baffle which likes 70's or higher. They like a cabinet.  If you want to really go all out and have the room, a pair of the Imperial Horns in our DIY section would be spectacular.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/11/19 at 03:17:31


BIG BETSY UPDATE

Bob Ziegler and I will be building another pair of Big Betsy baffles before the fest starts in 23 days here at Decware in my new shop. This way we can work out many of the details that will help determine pricing.

I will of course post the build here in this thread.

This will be the first time Bob and I have built anything together since I flew to Arizona to show him how to build a pair of corner horns many many years ago.

We have already discussed at length how to make an affordable alternative to the Solid 2 inch thick hardwood models so that everyone not willing to DIY a pair of their own, can afford to own a pair of the official speaker.

Solid pine was ruled out because by the time you join it up the labor is exactly the same as hardwood and I'm not sure it's dense enough.

MDF and particle board were ruled out because as far as sheet goods are concerned nothing is actually better than baltic birch plywood. Even though it is more expensive and we're going to laminate 3 sheets together in a vacuum press, the end result will be ultra high quality and have a similar sound. I'm sure the baltic birch pair will be less than half the price of the hardwood models, so that gets me excited.

Our intention is to offer the Budget Big Betsys in either Black or Clear finish. The pair we plan to build for DECFEST will be a clear finish and at least as thick or thicker than the hardwood models to ensure similar performance.

-Steve







Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/11/19 at 13:54:33

I think this is great that you’ll be offering these in a budget build.  I’ll look forward to hearing the different builds at the fest.

I am putting together my BB playlist and have some songs that will hopefully show off what these speakers can do.

If you have ever found yourself thinking that you get great transparency with your tube amp but limited volume or hit, this is a speaker for you.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/11/19 at 16:42:51

I'm looking forward to seeing your vacuum press.  That will be the key to the build -- no voids.

Title: Re: Steve's BIG BETSY Project
Post by HDDR1 on 09/11/19 at 18:10:33

Great to hear about your plywood baffle build Steve.  If nothing else I want to possibly build a prototype out of plywood and if I like it enough in my own room then build the artistic version of this.  My brother has a very expensive slab of Claro Walnut he would sell me (I think $2k) at his cost that I could make 2 baffles and a short dining room table out of.  The speakers would look and sound awesome - and then I would need to work the electronics end and get your Anniversary Amp and Pre.  1 step at a time....

I have not been to Decfest before - is there a good thread to read what it is all about, tentative plan, etc.?

Best wishes and you truly rock!

Ken

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/11/19 at 18:38:33

This will get your started:

https://www.decware.com/newsite/zenfestcam.html

I've attended the last 5 (6??).

Its about as laid back an audio event as you'd ever attend.  No set timetable other than start and finish.  

It's held at Steve's production facility which is behind his residence in East Peoria.  He has a large yard where some people camp but most get rooms at surrounding hotels.

Great people willing to share their audio experiences and answer questions.  Steve is available to answer questions and generally BS with.
Bob Ziegler and Randy are also there to talk about speaker building and the latest versions of their speakers.

You can see all the Decware products and audition them in Steve's listening room which is part of the facility.  Occasionally, people bring their DIY or other equipment to hear it paired with Steve's gear.  CDs, vinyl or streamed music is always playing.

Generally, if there is a particular piece of gear that you want to hear, you ask and people take turns hearing their requests.  The room is set up so there are two "ends" and the couch flips and speakers are moved around to accommodate different listening setups like vinyl or CD.

People also take turns listening to the music they prefer as well.  They bring their own records, CDs, and thumb drives.  In recent years, there has been more sharing of playlists from Tidal, etc.  I have found it to be a great source of new music.

Listening sessions go late into the night and resume early the next morning.   People float in and out of the fest.

Its just a good laid back, informative and very entertaining get together with nice people who know a great deal about audio.  No hype.  

It also makes a lot of sense if you are looking to buy some of Steve's gear as it can save you a lot of shopping time and actually hear what you intend to buy without worrying about a trial period, back and forth shipping, etc.  

My first fest led to a Rachael purchase and started me down the Decware road.  My last fest led to my 25th anniversary Zen purchase.  I'm ashamed to admit all the purchases in between ;)





Title: Re: Steve's BIG BETSY Project
Post by HDDR1 on 09/11/19 at 19:01:21

Thanks for the good advice and great info.  Sounds like something I would enjoy - now I just need to see if I can clear my calendar for 4 days to drive over to East Peoria from the Kansas City area.

Thanks!

Title: Re: Steve's BIG BETSY Project
Post by lazb on 09/11/19 at 20:27:03

HDDR1, I took the plunge and made the 500 mile drive from Little Rock, Ar. and have never made such a good choice in my decades long audio journey! Come have fun, treat your ears deliciously and chances are extremely good it will be the beginning of a happy journey for you as well!

Joe Lazenby (Lazb)

Title: Re: Steve's BIG BETSY Project
Post by Showme on 09/11/19 at 20:31:51

Stoney Creek Resort/Hotel is the closest hotel and it was certainly good enough for me last year that I booked it again this year.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/11/19 at 20:31:58

Oh, and in years past, Steve has also given a coupon for % off your next purchase for Decfest attendees.  If you intend to buy, it can help offset some of your travel expenses.

Title: Re: Steve's BIG BETSY Project
Post by Brian on 09/12/19 at 04:01:03

Hello radarek.
I am glad you decided to join the communication. I hope you enjoy the talk here.

Brian

Title: Re: Steve's BIG BETSY Project
Post by Radarek on 09/12/19 at 15:29:22

Thanks Brian

The talk is what brought me here. I see why Decware is so successful half is the product and half is Steve...

Best regards

Title: Re: Steve's BIG BETSY Project
Post by Brian on 09/13/19 at 04:19:47

Ha Ha Ha!
That is so true!

Brian

Title: Re: Steve's BIG BETSY Project
Post by Bottlehead on 09/13/19 at 05:18:02

Well said, Raderek.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/13/19 at 05:21:57



Quote:
Great to hear about your plywood baffle build Steve.  If nothing else I want to possibly build a prototype out of plywood and if I like it enough in my own room then build the artistic version of this.  My brother has a very expensive slab of Claro Walnut he would sell me (I think $2k) at his cost that I could make 2 baffles and a short dining room table out of.  The speakers would look and sound awesome - and then I would need to work the electronics end and get your Anniversary Amp and Pre.  1 step at a time....

I have not been to Decfest before - is there a good thread to read what it is all about, tentative plan, etc.?

Best wishes and you truly rock!

Ken


Hi Ken,

Yes, the solid slabs are an exciting proposition! Perhaps we can see you at the fest and you can hear the originals as well as an entire room full of speakers for perspective.  If not, definitely post your builds here so we can enjoy your results with you!

Thanks,

Steve

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/13/19 at 16:49:39

I may have missed it, but you should post your Crystal 10 video here Geno.  Sounds pretty sweet to me and I only listened to it on my phone.  You definitely have my attention.

Title: Re: Steve's BIG BETSY Project
Post by HDDR1 on 09/13/19 at 19:05:07

Steve,

I really need to get up to your place for DECFEST or another time very soon.  I have been following your products and forums for 3 years now and I flat need to hear your amps, the ZOB, BBB, BBjr, DNA2, and HR1s etc....  I have never heard tube amps other than MacIntosh @ Best Buy (exactly....) so need to hear the real deal with your amps.  I think I want a tube amp (SE no feedback with serious design chops like yours), I think I want resolution like the ZOB or BBjr.  BUT until I hear everything I won't know - it would be awesome if I preferred the BBB.  I strongly suspect at the end of the day I will have to make both and drive it them with your amps.  If I get to the builds anytime soon I will definitely post updates here and share what I learn - I have a few ideas I would want to experiment with.

Thanks,

Title: Re: Steve's BIG BETSY Project
Post by Geno on 09/13/19 at 19:29:11

I'll post it now, Pal.

A video of my Crystal 10 baffles:  https://youtu.be/cNq_gHwLa3Q

*Bass is augmented with two 12" Alpha Bass Baffles (from Caintuck Audio) and a REL T5 Sub

Geno

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/14/19 at 04:29:24


Well after a long and somewhat trying day I am amazed at how fast it all melts away with the Big Betsy / F15 combo and a Zen TORII MK4.  Wow, what a combination that is.  I just had a demo where the clients were interested to see if DECWARE low power tube gear can compete with their solid state 1200 watt RMS bi-amped system, and the Big Betsy / TORII MK4 spanked its ass pretty bad according to them.  I would hope so, because they're measuring 108dB at the couch and it was louder than that in the hall way.  I had to put headphones on just to keep my head from exploding. Amazingly everything held together just tight as a brick with no audible distortion.  I've never actually heard the speakers anywhere near that loud before, and was somewhat shocked at how WELL they graced through it like it was nothing.  I mean it was beyond seriously loud.  

It was also painfully evident that the TORII MK4 simply  L O V E D  these open baffle speakers, as it does all open baffle speakers.  It was always the amplifier of choice with my Zen Open Baffle speakers, but the same amp on the Big Betsy /F15 combo simply embarrasses the ZOB beyond belief.  It was the first time I head what a TORII MK4 cranked up to the wood can actually do.  Simply amazing.  He wanted the ZMA but after that demo, likely going to save himself a couple grand.

I never heard anything that loud in this building since we moved in all those years ago.  Literally I have never heard anything get that loud in the room without loosing it regardless of power and who is it that comes running through the smoke cloud with the checkered flag but the TORII MK4 with Anniversary mods.  Simply amazing.  Boy if you like bass hit this combo will crush everything. And it will go exactly twice as loud as you can possibly stand.  If you applied the 1dB per beer equation to this combo, you would die of alcohol poisoning before you got the amplifier to clip.  

I've put in my share of  night club sound systems over the years and this hit like that on a night when everyone was on steroids... and the rack of solid state amplifiers and 18 inch subwoofers were about to melt down in unison while everyone mistakes the smoke for dance floor fog machines.  

I was amazed to find the knee point in the listening room is higher that I would have guessed. Most impressive were the damn speakers because they were just setting there, you couldn't even see the cones moving more than a tiny fraction of an inch and yet the building was being wrecked like a live concert.  ZERO stress, distortion or compression.  ZERO.  ZERO.

So it is great to turn on this combo at a 1 watt level and let it just play with the music and my mood.

Yes, this years DECFEST will actually have to have an SPL warning alarm in case someone tries to play these speakers too loud. Probably just a SPL activated orb that floats around the room and shocks offenders with mini lighting bolts.  I'm working on it now.

-Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/14/19 at 04:46:20



Quote:
Steve,

I really need to get up to your place for DECFEST or another time very soon.  I have been following your products and forums for 3 years now and I flat need to hear your amps, the ZOB, BBB, BBjr, DNA2, and HR1s etc....  I have never heard tube amps other than MacIntosh @ Best Buy (exactly....) so need to hear the real deal with your amps.  I think I want a tube amp (SE no feedback with serious design chops like yours), I think I want resolution like the ZOB or BBjr.  BUT until I hear everything I won't know - it would be awesome if I preferred the BBB.  I strongly suspect at the end of the day I will have to make both and drive it them with your amps.  If I get to the builds anytime soon I will definitely post updates here and share what I learn - I have a few ideas I would want to experiment with.

Thanks,


All you need is a little encouragement to actually show up in 20 days 11 hours for the fest. You'll be in the best of company as myself and many of the people who have become regulars put together systems of your choosing so you can hear them first hand.  There is no substitute for that.  You'll leave knowing exactly what speaker and what amp you will have and save yourself years of guessing and second guessing.  Plus the beer, food, and bonfires set a tone someone like summer camp when you were a kid vs. in your face marketing hype and high energy blah blah blah so maybe you'll buy something.  We don't worry about attendees buying something because somehow 10 years later they all have a whole collection of Decware gear and will likely live longer as a result which comes in handy for enjoying it.

-Steve

Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/14/19 at 18:09:46

Geno, I can't say anything about the fidelity since I listened through my crappy computer speakers but your setup looks fantastic.  I love the grills.

If Steve is to be believed, and I generally do -- blindly, get a ZROCK2 and ditch the subs and sub amp.

I did get a little woozy with the floating sway.   ;)

Title: Re: Steve's BIG BETSY Project
Post by Geno on 09/14/19 at 20:48:45

Thanks, Adam. The metamorphosis of these drivers is amazing. The change in the last 2 days has been quite something. Listening this morning, I just had to shake my head. And I’m prolly still 30 hours or so from break in. Lii advised about 30 days break in, in an open baffle configuration.


Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/14/19 at 21:11:02

Hey Jeff, have you got your Crystal 10s up and running?

Title: Re: Steve's BIG BETSY Project
Post by Andy P on 09/16/19 at 18:01:23

Hi Steve, I am looking at the drawing you posted and I am wondering what the dimension of the flat top and bottom are and also what is the width of the base? I am going to cut the panels out on a CNC router tomorrow. When I look at the drawing I am not clear as you call out the dimensions of the boards and it does not seem to match up with the overall width. Using Ash and white oak.  Thanks. Andy

Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/16/19 at 18:43:00

Andy, you'll have to look for it but in a later post Steve tells us his exact build dimensions.  The drawing was only his starting point.  Steve's post comes after many of us were discussing variations in our build/calculations.

Edit:  I did the work for you.  Look at Steve's post, #200 at the top of page 5. 

Title: Re: Steve's BIG BETSY Project
Post by Andy P on 09/17/19 at 12:07:14


Quote:
Nevertheless my final shape that I ended up with is slightly more stubby which from an artists eye better serves the 15 inch driver I planned to put in it. So if I measure my pair of Big Betsy Baffles, the actual width came to 33.75 inches. The width at the top and bottom were 22-13/16 and the height came to 42-1/8.


There it is!  Thanks for bringing it to my attention. Great post with lots of good info. Thank you all for generously sharing.  I will post more pics of my build ASAP. Thanks. Andy

Title: Re: Steve's BIG BETSY Project
Post by HDDR1 on 09/17/19 at 15:31:11

Steve,

How do the Big Betsy Jr's sound with the Torii IV?  I presume the ZROCK2 would still be needed to the same level as before - just curious about that pairing.

Thanks,

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/17/19 at 17:17:08

The pairing is fantastic.  Because of the TORII MK4's love for open baffles, the base performance is more than reasonable without the ZROCK2.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Andy P on 09/18/19 at 02:44:39

Cut out the big Betsy panels on the shopbot today and it actually worked! I am pretty excited to build the bases and mount the speakers. Steve, so you know, after hearing your Big Betsy's, not a full day passed before I ordered a set of the 15" speakers from Lii Audio!

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/18/19 at 16:11:16


Hehe,  Andy's not messing around! That's pretty cool!



The edges look pretty clean too... be anxious to see how they turn out!

Steve

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 09/18/19 at 21:55:15

Andy, That is the only way to do it!

Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/19/19 at 00:48:42

Has anyone changed the binding posts on their F15s?  I don't care for the way they hold my solid 14 ga wire and I'm thinking of adding silver over copper banana plugs to the wires and silver over copper binding posts to the F15s.  Any suggestions would be welcome.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/19/19 at 01:18:45

Archie,

The silver banana jacks on our speaker wire fit perfectly in the hole so that means any banana jack will also.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/19/19 at 01:29:14

Thanks.  Do you think the "guillotine" contact is adequate?  Just to be clear, my F15 binding posts do not have a rear hole, only the spring loaded side hole.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/19/19 at 13:49:14

This is how I connect my BBs to styx wire with silver bananas.  Pretty solid contact.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/19/19 at 17:23:19

Thanks.  I'll get some bananas but I'm still thinking I might change the posts too.  There are some reasonably priced silver over copper on ebay.  All the sellers seem to be in China for this type of thing.

Looking at all of the base metal and plating options it's amazing how relatively poor conductors some of these are by comparison to silver, copper and gold.  Here's a chart I found:  http://eddy-current.com/conductivity-of-metals-sorted-by-resistivity/

Cardas uses Rodinium over the silver plate over a copper base.  The Rhodium is to protect the silver from tarnish but it's a really "bad" conductor.  Seems like a huge step backwards.  Brass is terrible too.  And forget about nickel!

Title: Re: Steve's BIG BETSY Project
Post by maddog07 on 09/19/19 at 20:57:32

Cardas makes solid copper versions.... no plating of any kind - you're responsible for cleaning them occasionally.

and if you want some solid copper "split tensioned banana's" C14500 93% IACS Tellurium Copper - go to Douglas Connections and get some of the Furez - best banana I've ever seen and/or used in my life.  These banana's "stay tight"... no matter how many times plugged/unplugged and their is no outer spring barrel to get loose and/or break off like always happens with that type of banana.

https://douglasconnection.com/product/furez-tstsb40np-bare-copper-banana-plug-connectors-pair/

you can get them in screw on or crimp/solder and with or without a barrel to dress them up.
They're also available in Silver if you subscribe to that camp.


Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/20/19 at 01:03:55

Those Furez look nice.  I like the rubber plug that must keep them tight.  Another company I came across that has all kids of copper with or without different plating is Viborg:  http://viborgaudio.com/en/Product/FASSDFA/

I like those Cardas Cu binding posts.  It's harder to find nice copper or plated over copper posts.  The brass base metal posts seem to work okay but now I'm wondering if copper end to end wouldn't be better.  I'm not sure I'm ready to crack my ZMA but I can't see it being too challenging to try.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/20/19 at 04:27:17


So this will be an interesting side theme...  having become very fond of the Lii Audio Crystal 10 drivers in my open baffle design, I jumped at the opportunity when Lii Audio wished to attend this years DECFEST2019 but since they are in China they instead wished to send their flagship speakers as their ambassadors.  Lii Audio is a small company about the size of Decware with similar goals about hi-fi, so we have embraced their creations and are happy to share them with our customers at this years fest!   

If you've been reading this thread you are up to speed on my impressions of this 10 inch driver.  It was no mistake designing a high-mass hardwood open baffle for it.  The transparency is reference grade at any price league.

So now we have the same driver, in a cabinet that was designed by the owner and designer of the Crystal 10 driver (and F15 driver) so of course we HAD to hear that!



As you can see they make the Big Betsys look small, as well as all the other speakers in the room!  These are probably at least 10 cubic foot cabinets with a very clever design.  The Crystal 10 drivers have an fs of 30Hz and in these giant cabinets they can simply crush you.  100dB of 30HZ at 1 watt without even trying. The bass is so big and deep, as you would hope from a 10 inch driver in such a large cabinet. They certainly don't disappoint.

It's starting to twist my head a bit as they break-in...  The Big Betsy has more hit and bigger bass presence with the F15 driver, but this cabinet has almost an octave lower bass and it's flat bass, not rolled off. It can simply wreck your room with ease and you won't even see the cones moving.  

At first I was somewhat put off by the large size of these speakers, but the sound actually more than justifies it. There is no audiophile or audiogearhead that these wouldn't set a new standard for, like the Big Betsy but delightfully different. The bass is insane. It's a blast back to 1950's when giant speakers and or infinite baffles were popular.

This speaker is proof that real bass comes from speed and cabinet size, not power handling or multiple drivers. When you hear these, especially after either attending the RMAF or watching video reports of the show, you will just shake your head. Flashbacks of the giant speakers, with subs, and massive amplifiers and giant cables everywhere simply sound like a poor impostor for these. A single 100dB driver is kicking some real ass as it outperforms those huge 5 way speakers loaded with 84dB drivers.  It's a contest that isn't even a contest, and the fact that you can beat the high power high dollar world with a 2 watt Zen Triode Amplifier and these speakers makes me happier than shit.

Happier than shit because it proves that the low power Zen Triode amplifiers are actually better performance in all regions than high power tube or solid state.  The bass is tight and natural with WAY more hit and spank.  Trust me, it's like a different planet.  If you go to Mars you better abandon your earthly habit and conceptions because nothing is the same... it's like that when you hear this.

Real 100dB full-range drivers with no peaks and no weaknesses are thank God back to stay thanks to Lii Audio.  I consider it as serious a contribution to serious hi-end as Decware.  Drivers like these we can do great things with!  The designer's cabinet sets a nice benchmark that will be hard to beat.  I mean seriously, this makes hi-fi speakers sound stupid, it really does.  94dB is what it takes to really enjoy 2 watts without feeling restricted.  6dB on top of that feels like you just inherited 500 watts of the cleanest power you ever heard and now you can play the speakers so loud that pictures can literally fall of the walls!  

Another bonus of the large cabinets, is that the bass is not pressure centric.  At very low volumes the bass drops and is still easily heard and felt more so than most speakers in fact.  Very realistic when you can have such depth and scale at such a low volume.

How many hi-fi speakers do you know that can accurately reproduce a subwoofer better than the subwoofer itself?

Fun stuff, and it's real. I know I have to say that because I sound like hyperbole.  rust me this shit is going to re-arrange about 95 people's heads at this years DECFEST2019.

Steve



Title: Re: Steve's BIG BETSY Project
Post by Geno on 09/20/19 at 04:40:28

That’s awesome, Steve. And I love the look of the cabinets. After you’ve had a chance to listen long enough for a good evaluation, I’ll be interested in your opinion of the differences between them and the open baffle configuration. Mine in open baffles just keep getting better. I’m very happy with them!

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/20/19 at 04:54:44

Me too!  However as I set here listening to these drivers ease in and relax in these large cabinets it actually has me questioning the OB which is pretty impressive so soon in the game so I would predict that they are similarly equals but in different ways which is to say each has it's own strengths but are in exactly the same league.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/20/19 at 05:08:05


Andy, you're killing me with this only "one" photo crap.  Come on, let us watch!  I am really intrigued by your CNC.  It's mean to post only one pic.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/20/19 at 14:01:22

Speaking of which, will you be doing a teaser video of the Crystal 10 speakers prior to the fest???

Either my brain is adapting or the Big Betsy's have reached maturity.  Bass is so sharp, everything is very clear and the sound stage seems deeper and more focused.

I've had a couple of mind blowing fest moments over the years - imperials with your OBs and zen amp (big cabinet bass), the OTL amp (soundstage).  Generally one every fest or so.  This year could be a double or triple mind blower for sure.

Title: Re: Steve's BIG BETSY Project
Post by Andy P on 09/20/19 at 17:09:07


Quote:
Andy, you're killing me with this only "one" photo crap.


Hi Steve, thanks for the nudge!  I will post everything I have and share a link. I have a few vids of the bot. If you can find one to use, and in my case, someone to help with the operation of the thing, then it is fast and accurate. I used a 1/2" downward spiral bit, 2 1/4 cutting area. Ate it up.  No tear-out at all.

I am planning a trip to Deckfest with my son, Karl.  Looking forward to seeing meeting people and hearing some great sounds.  

Thanks for the inspiration!

Andy


Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/20/19 at 18:57:15

I placed an order for some nice Cardas copper binding posts:  https://www.moon-audio.com/cardas-ccbp-l-binding-post.html#tab-label-description-title

And some copper Furez banana plugs:  https://www.avoutlet.com/av-cables-connectors/av-connectors/speaker/furez-tst-w25np/   These will crimp on and soldier to my solid 14 ga wires (they come in various sizes).  They are so reasonably priced, I bought eight to do both ends of my wires.

I checked the F15 driver binding post mounting point and they are drilled at 1/4" so I'll ream to 5/16" for the new posts. The existing wires look long enough to soldier -- just barely.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/21/19 at 04:59:49


Tonight I have been getting the listening room ready for the fest.  I've been listening to all the speakers today and tonight I have landed on the Big Betsy Jr. without a ZROCK2 because my personal anniversary modded unit was used as a build sample this week.  So I have to listen to them just raw with no help whatsoever.  This after spending much of the day listening to the same Crystal 10 drivers in giant cabinets make the earth shake with 30 Hz bass, I figured this would be the worse case scenario.  How could I like them after that...right?  

They are so good with hi-end sources and amplification that I don't even really care about the ZROCK2.  I actually don't miss the bottom octave of bass in fact I find that I forgot it was missing because I get swept into the midrange and imaging and immediacy that they have as a result of the massive projection (crunch factor) that comes with this size and shape baffle.  

So the fact that I actually liked them best of all at the end of the day, and without a ZROCK2, although it would have been nice, speaks volumes for these as a serious reference speaker to try and beat.  I have no doubt that this is going to wreck the serious ears who attend the fest, and I know I keep saying it, but it is happening with 2 watts with lots of headroom.  

Of course it's a package sound if you will.  The most exotic drivers, baffles, amplifiers fed by really good sources.  I will definitely do a teaser video when I get the microphones set up again.

Steve

Title: Re: Steve's BIG BETSY Project - Naming it?
Post by Steve Deckert on 09/21/19 at 05:16:28


As a side note, since we are destine to make and sell these amazing speakers, we are going to be changing the names to avoid any conflicts or confusion with Wild Burro Audio's 8 inch "Betsy" driver.  

I was originally going to change it to BOB.  Big Open Baffle.  But certainly someone is using that who has just not registered it.  Then I figured, well, Zen Big Open Baffle.  ZBOB.  I liked it at first, along with ZBOB Jr., but then I realized no-one is going to want to spend 1000's on an exotic high mass open baffle called ZBOB.  It would be like writing ZBOB on the hood of a Lamborghini.

I have something far more fitting in mind, and am researching the name and the marks now. As far as I am concerned, at 100dB of warm liquid sound, I wouldn't care if these baffles were the only speaker we made under the Decware brand.  They're that good.  So stay tuned, when I get the name and the mark finalized I will announce it here.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Bottlehead on 09/21/19 at 06:16:11

Steve,

The progress that you have made this year is really remarkable. You've pretty much turned everything that I thought that I knew about audio upside down. Guys like you don't get to retire. I mean, like, ever. You know that, right? Steve?

Randy

Title: Re: Steve's BIG BETSY Project
Post by Bottlehead on 09/21/19 at 06:18:31

P.S. I'm pretty sure that I've cracked your code. I bet the name that you have settled on is "BAOB". Which stands for "Big Ass Open Baffle". Am I right, or am I right?

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/21/19 at 07:01:33

as you can see by the time stamp, I'm still setting here tripping on my Crystal 10 baffles with the 25th Anniversary Zen Triode amplifier and preamp...  

No ZROCK2 tonight, we're playing fully bodied electronic music just to switch things up!

I have to say that the sound is so lucid it should be and absolutely has to be completely illegal in at least 54 countries.... including here. You know, listening to bass intensive music on speakers this tight really takes it to a new level.  It really does. I could reproduce the 30Hz notes, but it wouldn't be as taunt or refreshing as only something like this can be.

I am listening to my soundstage guru of electronic music, Borris Blank.  The CD is YELLO, Motion Picture.  The first two tracks wrecked me on this system, I can't even begin to describe it. The overwhelming term is lucid.  Like beyond swimming in the music, it took it to a higher place.  So tactile, it was like you were swimming in an ocean but had to stick your head into the sound to breath and the energy from it was so intense so clean, like ultra fresh air.

The Crystal 10 drivers are a force to reckon with in the lucid department.  Never heard anything this good.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/21/19 at 14:24:59

Well I finally got up the guts to see how the “speakers to be named later” compared to my previous speaker setup.

My previous speakers setup consists of a Dayton AMT pro4, Tang Band W8-1808 and Eminence Alpha 15A in a 1.5” Baltic Birch open baffle.  Crossover is a cap for the tweeter and coils for the other two drivers.  

I also have the two 15” Dayton Reference subs in ~3cf mdf cabinets run by dual Crown amps running in bridged mode putting out about 700 watts per amp.  Combined witht he OBs, this is about $2K in drivers/amp/baffle/cabinets/xovers.  

Also, I have been experimenting with driver combinations and baffle shapes for these speakers for about 2 years to get them where I like them.

The “speakers formerly know as Big Betsys” cost me about $625.  I haven’t applied a finish yet, but I have about 8 hours into the build.  A lot of that was just figuring out the cuts.  Depending on how much difference I perceive in my baffles vs Steve’s, I may double up the wood in my build for another $175.

Anyway, I am happy to report it wasn’t a complete rout.  My previous speakers held up well, but there were some key differences.

Presence: I immediately noticed that my old speakers were very much “you are there” versus “they are here”.  I like both, but the BBs seemed more intimate.

Volume: For my previous OBs (about 94db) I ran them at about -4 to 0db on the TEAC with the Zbit at about 2-3 oclock and the 25th Zen wide open.  

With the BBs, keeping the Zbit and amp the same I typically run -14db on the TEAC and that is too loud on the recently mastered stuff.

Hit/Bass:  My old speakers don’t have the “hit” of BBs.  I immediately switched on the subs.  I got good low end bass but I felt it more in my butt than my chest. With the BBs, I feel it more in my upper body.

Switching on the subs was an interesting exercise because with the old speakers, the subs make a big difference.  With the Betsy’s they don’t and I figured out why.  They can’t keep up with the BBs.  The BBs are so efficient that I can’t get comparable volume out of the subs, even with the Crowns cranked.

Open Sound:  Here is where my old speakers have the edge.  The baffle width is three tier, with the bass driver tier about 22” wide and then about 12” for the mid and only 7” for the tweeter.  So there is less surface area to block the sound waves coming off the walls behind the speakers.  This combined with the “you are there” sound of speakers leads to a more open sound stage.  Keep in mind that the BBs are huge and my room is small (12X16).  And in no way do the BBs have a small sound stage.  Quite the opposite.

Detail: My old speakers were simply not a clear as the BBs.  They sound just a slight bit congested.  I got used to this throughout the course of the evening, but I think when I put the BBs back in, I will notice it big time.

So my old OBs are not headed to the trash bin, but the efficiency combined with the clarity and hit of the BBs make them a more engaging listen.  Then you read through my description above to see what I had to cobble together to get the sound out of my previous speakers and I think the choice becomes very clear for the non-DIY masochist

I can tell from Geno’s video that the Crystal 10s will “wreck” me as Steve says.  I think they are going to give me what I have been looking for in speakers like the Pure Audio Project and Voxativ.  I can’t wait to hear them.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 09/21/19 at 15:01:27

Palo,
Damn it man, you are going to make me spend some money!

Title: Re: Steve's BIG BETSY Project
Post by Geno on 09/21/19 at 15:44:00

My experience with the Crystals is very similar to Steve’s. I started out using mid-bass baffles and a sub (instead of a Zrock).  I have finally realized, and as they have broken in more, that they are better with no supplement. Cleaner. The only tweak is a Zstage with phono and Zbit with digital. My amp is a SE84UFO (with 25th mods) and the Crystals are scary good. I can’t imagine how great the 25th Anniversary Zen must sound with them. I guess that eventually I’m gonna have to find that out...

Title: Re: Steve's BIG BETSY Project
Post by Geno on 09/21/19 at 19:07:29

Here is another video of the Crystal 10’s:  https://youtu.be/b_yrG3ZzE1g

Title: Re: Steve's BIG BETSY Project
Post by HockessinKid on 09/21/19 at 19:26:22

Geno,

Damn!!!!! Those look and sound great. I think I'm going to in for a real treat at Decfest, and most likely a lighter wallet😆.

HK

Title: Re: Steve's BIG BETSY Project
Post by Nixxuz on 09/22/19 at 06:01:13

Hi all, I was previously looking into a pair of the F15 drivers in a straight OB, with maybe an Eminence Alpha 15A backing up the low end, since I have a pair sitting around doing nothing at the moment.

But, since I currently have a semi-OB pair of speakers going, I wondered if the magic that seems to be inherent in both the F15's and the Crystal 10's would also show up in the new Lii FAST 8's? I'm curious as I have been using a combo of the Dayton PS220-8's with a little shine on top from some HiVi RT2C's. That portion of the speaker is powered by a fairly modded Yaqin MC13S running KT77's. The "enclosure" part of the speakers houses dual Goldwood GW-PC8-8's in a roughly 3 cu vented box, running off a Crown XLS1000 with it's internal crossover set to around 150hz. I'm thinking, since the cutouts are almost the same, of swapping out the 220's for the FAST 8's. But since they are so new I figured it wouldn't hurt to ask if anyone has managed to try them yet. $199+shipping is pretty easy on the wallet, especially considering I wouldn't need all new baffles for them.

Title: Re: Steve's BIG BETSY Project
Post by ScottNC on 09/22/19 at 14:26:37

Geno,
Nice video, thanks for putting it up!
Your room looks great with those in it!
Scott

Title: Re: Steve's BIG BETSY Project
Post by Geno on 09/22/19 at 15:02:48

Thanks Scott and HK. They are winners for sure!

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/23/19 at 22:00:34

Hey Geno, what are the songs in your two youtube videos?

Title: Re: Steve's BIG BETSY Project
Post by Geno on 09/24/19 at 04:16:50

Tom, the 2 from today were Little Feat - Spanish Moon (Live) and Vivaldi - Summer (3rd movement) from The Four Seasons.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/26/19 at 12:39:49

Thanks Geno.

I put the Big Betsy’s back in after swapping them out for my other OBs.  I was instantly impressed all over again.  I stand by what I said a few posts ago but can safely add there is better overall coherency to the BB that I’m missing in my other OBs.  Also I think my other OBs have to be driven hard to approach the fullness of sound that I get with the BBs.

I am getting some new bass drivers today that have been on order for over 4 months (well before Steve turned us on to the BB).  I’ll put them in my other OBs and see how they sound.  I’ll run those speakers while I finish the Big Betsy’s.  I ordered and received some Danish oil.  I also made the additional wood braces/supports for the bottom of the baffles out of red oak so I’ll install those.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 09/26/19 at 17:03:53

Danish oil!!? Palo you know better than to trust the Danes!

Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/26/19 at 17:35:22

I'll chime in with my Watco (Danish Oil) anecdote.  I was oiling my unfinished butcher block counter tops many years ago and I wanted the best oil finish for max protection.  I used cheap linseed oil on the bottoms and expensive Watco on the tops.  I got a ring of linseed oil on the tops but I didn't worry about it since I figured the Watco would just blend with it.  It turned out the the linseed oil sealed out the Watco and after many coats of Watco (following the directions carefully) the first time water got on it, it raised the grain.  I called Watco to inquire and they admitted that their product was "basically linseed oil."  Yeah, and at 3 times the cost!

"Danish Oil" is a scam.  Linseed or Tung are the real deal.  If you want a more water resistant finish, just add 1/3 part polyurethane with 1/3 thinner and 1/3 linseed and use like a straight oil.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/26/19 at 17:45:47

Its basically linseed oil that has been polymerized.  I really just looked for the lightest finish that had the best reviews.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/27/19 at 16:07:12

Boiled Linseed does give an amber tone to the wood.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/27/19 at 16:25:40

I found some comparison on the web and this particular brand of linseed was the lightest.  I am not that hung up on it but I want to experience doing a linseed finish.

I got my acoustic elegance 15" drivers last night and put them in.  So far, they are the only drivers that match the punch of the F15s.  Maybe exceed it, but $$$$$.  If I get a chance, I'll update the Palomino Audio Project thread.  They are very nice drivers.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/27/19 at 16:38:46

I just buy what's in the hardware store.  Many years ago I'd buy it in 5 gallon cans.  Those were the days when I learned how combustive a wet rag could be.  I walked by a smoking rag sitting on top of a pile of my wood flooring.  Oops.   ::)

Title: Re: Steve's BIG BETSY Project
Post by HDDR1 on 09/27/19 at 17:35:33

So which version of the Acoustic Elegance 15" did you get?  If I were to build a 2 way open baffle those would be on the top of my list to handle the lowest frequencies using a simple inductor.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/27/19 at 17:41:57

LO15 with a simple coil, crossed at 250hz.  I think you could easily go higher.

Seems louder than its stated sensitivity.  Could just be a good match with my 25th.

Title: Re: Steve's BIG BETSY Project
Post by Adriankn on 09/27/19 at 19:00:58

For someone that doesn't want to DIY and cannot get away with the aesthetics of the Big Betsy in my livingroom, would you recommend the Crystal 10 speaker by Lii Audio?

I showed them to my SO, and she fully approved them. Even knowing they are large.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/27/19 at 19:28:58

Based on Steve's account and what I heard in Geno's YouTube videos, I would say yes.  The people with the driver might offer a better opinion.

You could also consider Randy's smaller baffle for the L15.  It just depends on budget.

Title: Re: Steve's BIG BETSY Project
Post by Adriankn on 09/27/19 at 19:56:56

Thanks. I'm interested in Steve's take on the differences between the BB and Lii's Crystal 10, since they're both in the room. However, I doubt I'll be able to get away with an OB at all due to the finished look. My wife really likes the Crystal 10. I'm blessed that way!

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/27/19 at 20:00:01

Did you see his comparison earlier in the thread?  Or are you saying you did?

Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/28/19 at 00:19:33

As I mentioned in an earlier post I decided to replace the binding posts on my F15 drivers and I added banana plugs to my speaker wires (both ends).  I used solid copper posts and plugs.  I had quite a learning curve as I attempted to soldier in a relatively tight and hard to get to space and to something which was a huge heat sink.  Maybe not the prettiest job ever but if I didn't actually improve my sound, I'm having one heck of a placebo effect.   8-)

Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/28/19 at 00:21:00

The really hard part:

Title: Re: Steve's BIG BETSY Project
Post by will on 09/28/19 at 01:16:17

Hey Archie,

I wonder if you have a solder gun? If not, more power really makes a difference soldering those heat suckers. Heating faster, it is also more focussed, in and out faster helping avoid damage to things when you need a lot of heat to get a good joint.

During my several year amp modification trip, Cardas Rhodium Flashed Silver on Copper binding posts were recommended as very good and very popular by a long-time DIY'er and parts provider. At that point, I had done quite a lot of power supply bypass tuning, improved volume pots, coupling caps, improved RCAs, some resistor and wire tuning..... Everything that stayed was a sound tested improvement, mostly one thing at a time in order to fully identify results.

When I replaced the stock posts with these Cardas, there was a fair bit more to hear because the amp had become more responsive and transparent, but both my wife and I thought the binding posts were the biggest single improvement to date. And there were some big ones before! Luckily had a solder gun, so, though harder to solder, it went relatively easily.

So for my preferences, experimenting with lots of caps, parts, wires, cables, tubes... the Cardas Rhodium flashed Silver on Copper posts are pretty world class sounding regardless of theory of conductors. Earlier on in mod work, by some technical views, even more egregious, I had really liked a Rhodium plated Furutech IEC in the Torii, to me a notable improvement also over stock, more solid and open. So I was not concerned about the Rhodium "flashed" binding posts. This is from my notes after changing to the Rhodium plated IEC: "Though similar in clarifying across the spectrum with the Jupiter VT/Mundorf Silver Oils in the HR1s, and to the Jupiter Coppers coupling caps in the Torii MKIV, in many ways it is a better change than any caps or tubes I have tried. Once burned in and settled, the IEC was more pronounced and complete in clarity without any problems. Clearer, more micro detail, better bass resolution, quieter, sweeter..."

Though Rhodium is not for everyone, and some designers use it better than others, and, even for better designs, synergy is still the bottom line... I think tech specs can be quite useful, but sound is always the final determinant for me.

I have not heard your pure copper posts, but am impressed with Cardas, and can imagine they would sound great. It is good to hear how much you are enjoying your system!

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/28/19 at 03:34:48


UPDATE

Bob Ziegler is here and we have the baltic birch to build both the Big Betsy and the Big Betsy Jr.  I think we will probably dive into it after breakfast tomorrow morning.

Today all day and even as I write this, we have been in the center of the what is presently the largest storm on the planet.  It's been a little hairy as we were almost hit by lightning this morning, and getting nearly flooded complete with near tornado misses... Bob's just loving it.



This is the real time lighting map as of minutes ago.

Anyway, I'll take some pictures of this new Baltic Birch Big Betsy Build as things progress and post them tomorrow night.  Should be fun!

Steve

Title: Re: Steve's BIG BETSY Project
Post by Brian on 09/28/19 at 03:40:13

Have the Big Bettys, or any Lii F-15 speaker, been heard with the Single-ended Pentode MINI TORII amp?

I am especially wondering how the sound would compare to the SE84 Anniversary amp.

Brian

Title: Re: Steve's BIG BETSY Project
Post by Brian on 09/28/19 at 03:48:26

I hope you have no storm damage!

Brian

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/28/19 at 04:28:58



Quote:
Thanks. I'm interested in Steve's take on the differences between the BB and Lii's Crystal 10, since they're both in the room. However, I doubt I'll be able to get away with an OB at all due to the finished look. My wife really likes the Crystal 10. I'm blessed that way!


I am assuming you mean the Crystal 10 drivers in Lii Audio's own cabinet which we have recently received, and while still breaking in, the initial take away when comparing it to the Big Betsy, is that the Big Betsy hits harder, the Crystal 10 cabinet hits lower.  Big Betsy sound stage is bigger and the speaker has more projection.  This is expected due to the physics of the Big Betsy open baffle design vs. a ported box.  As far as ported boxes go, the Crystal 10 is cleverly designed to minimize internal reflections and parallel surfaces for a surprisingly clean sound.  The top of the box has some resonance that adds energy to sound and may have been intentional, however it can be deadened with a sandbag or similar approach if you prefer.

The Crystal 10 cabinet is larger than a Big Betsy so it's not a space saver, would be ideal in medium and larger rooms where you want to effortlessly fill it with a live majestic sound.  For $2500 a pair I can't think of anything better, and especially for those with our low powered amplifiers because these speaker will be like trading your 2 watt Zen Triode in on our 40 watt ZMA.  

Hope that helps,

Steve


Title: Re: Steve's BIG BETSY Project
Post by Geno on 09/28/19 at 15:52:06

You might consider doing what I did. I wanted the Crystal 10 in an open Baffle, but needed a smaller baffle. I let my room dictate the size I could accommodate. They ended up being about 3” smaller in height and width than Steve’s. I think they are the perfect size for my room. I will include a few pics.

Good luck,

Geno

Title: Re: Steve's BIG BETSY Project
Post by Geno on 09/28/19 at 15:53:24

The design that I used.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/28/19 at 18:10:17

Will, I bet the "debate" of rhodium vs not is orders of magnitude less important than my original case of the thin edge of gold plated brass that made point contact with my speaker wires.  What I have now is more like a solid wire connection.  I used some Graphene contact enhancer as well.

These Cardas posts are very impressive.  I only paid $68 for the two pair.  The Furez bananas recommended by maddog are simple and brilliant as well (and very inexpensive for the crimp and solder style).  They make firm (tight) contact.

It's amazing how seemingly small things make such big differences.  The F15 drivers really ought to come with better binding posts but at their price point I guess they don't want to increase 10% to 20% just for them?

Oh, I cranked up my solder iron to 850 degrees and put on my widest tip.  I doubt I could have fit a gun (which I don't have) in behind the speaker cone.  Cardas must anticipate high heat as the plastic they use didn't melt.

A point of interest to anyone who might want to change their F15 posts, the original hole is about 1/4".  I drilled a 3/8" hole and used a thin strip of electrical tape as an insulator between the post and the sides of the holes (installed after the post cooled).  The Cardas posts wanted a 1/2" hole but I didn't feel comfortable taking that much metal away.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/28/19 at 18:34:04

Interesting mod Archie.  I have those binding posts on my Rachael.  Never really heard the amp without them so I can’t comment.  I do clean them a couple times a year.

Are any F15/Crystal builders coming to the fest?

Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/28/19 at 18:48:07

Pal, You'd have to change the F15 posts hear if they matter for you.  With your bananas in the existing F15 post holes you probably already have better contact than I had.  Those spring loaded binding posts remind me of the cheap guillotine connections I always had on lower priced components.

Title: Re: Steve's BIG BETSY Project
Post by Adriankn on 09/29/19 at 00:12:36

Thanks Steve,

Without nitpicking too much over which edges out which in specific areas, sounds like the Lii Audio is great for the money.

Getting a nearly full range performance from a full range driver regardless of price is something I haven't heard yet. Buying a pair would be a slight gamble. But for where I'd put them I was most intrigued by the fact that I liked the look, my wife loved the look (even after I explained how big they are) and I could finally get a full performance out of a few watts from a speaker that I'd be allowed to own.

The Big Betsy and Caintuck's smaller take look super interesting, but didn't get a pass due to their looks.

Thanks Steve. Seriously considering these to partner with a Zen in the future.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/29/19 at 03:12:01

I'm thrilled that your wife likes the looks!  I'm sure you would be thrilled with the performance.  If I could get every 2 watt customer of ours to own a pair of these, I would.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/29/19 at 03:26:01




We started this build by making a template of the radius out of 1/2 inch MDF.  This was used with a flush trim router bit to create the radius on each side of a 3/4 sheet of baltic birch.  First we cut close to the line with a jigsaw, then use the router to make that final pass.

We decided to make the baffle from two 3/4 thick panels and one 1/2 inch panel sandwiched in-between.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 09/29/19 at 03:39:02

And no curse words were uttered!

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/29/19 at 03:58:09

Not yet, but so far all I'm doing is holding the camera, and turning on and off the vacuum. Of course I am telling Bob how to do it as we go... (yea right).  

Actually in fairness, Bob did curse the same demon summoning router that I cursed saying that it's just backwards. So now I feel better. Nevertheless because he brought his router with him, Murphy picked today to make the plunge function on his router non-adjustable so we had to use the one I recently bought. Actually come to think about it, that brought on some cursing too... but this kind of casual cursing doesn't summon demons.  When I put the router bit through the table top that day, I was pissed on an exponentially higher level.

So, no disappointments here... plenty of actuall cursing did take place, and as a machinist you know that cursing is what holds tolerances from getting too far out of whack.  

Steve

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 09/29/19 at 04:25:14

I'm used to cussing that make sailors blush.
Close work requires a lot of doubt in your coworkers  parents marital situation and perhaps description of some sort of sexual proclivities that are out of the scope of civilised discussion.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/29/19 at 04:52:46




Now that first layer is cut, the woofer cutout is next.




Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/29/19 at 05:07:01




Yup, there it is...

a 15-3/8" diameter 1/2 inch deep with a 14 inch cutout.  This top layer will be used as a pattern to cut the other two layers.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/29/19 at 06:29:52




Always a good idea to put double stick tape under the baffle and cutout so that it doesn't move when you finally cut through.







Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/29/19 at 17:58:03

I'm a little surprised that you guys are cutting layer by layer.  I guess you'll tidy up the edges once it's glued up.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/30/19 at 03:13:30




Now that we have the first layer cut for each baffle, we glued up the three layers as shown.  Bob didn't bring his vacuum press, so this is how you would do it without one.  Note:  The 2x4's are crowned so that there is more pressure in the middle.  Same with the Wenge scraps, both were slightly crowned, so they were perfect.  One of the 2x4 wasn't crowned enough, so we made it more crowned on the jointer.

When this dries, we will take a jigsaw  and cut the two un-cut layers as close to the top one as possible and then take a flush-trim router bit, using the top layer as the pattern, clean everything up.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/30/19 at 03:17:40




Here is what it looks like after the glue has dried.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/30/19 at 03:19:24




Here are both rear bases in part being glued up...


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/30/19 at 03:30:57




So using the top layer as the template, we will flush trim the radius, top and bottom and the woofer cut-out. The pilot hole is drilled and ready for the router.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 09/30/19 at 03:47:44



And with that done, we can start sanding.

Using one of nearly finished bases between the baffle and the table leg along with a clamp, we are ready to finish sanding the radius.

So as of tonight both baffles are done... the solid maple front feet are done and the rear bases are finished.

Tomorrow we will finish sand everything and then seal it with shellac and spray the speakers with clear lacquer.

I can tell you already that these will be every bit the equal to the solid hardwood Big Betsy that I started this thread with. They are nearly as heavy, I would say close in density and the look mean, and the look expensive. Since the original Big Betsy was 1-3/4 inches thick by the time I was done with them, we made these Baltic Birch plywood versions 2 inches thick.

We hope to have solid estimates of the costs of all three by Friday.

-Steve


Title: Re: Steve's BIG BETSY Project
Post by Nixxuz on 09/30/19 at 16:22:05

Well, seeing as the FAST 10 just went on sale on the Lii Audio site a little while back, I decided the price could not be beat and ordered a pair. Hopefully they provide some of the same sound quality as the Crystal 10's or the F15's.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 09/30/19 at 18:03:54

Let us know.  That is an attractive price.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 09/30/19 at 20:25:48

One thing I see about the FAST 10 is that the Qts is even lower than the Crystal 10 and significantly lower than the F15.  I assume you're intending it for OB?

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/01/19 at 14:04:44

Thanks for sharing Steve.  I like the template idea.  I am thinking about adding another 1" panel to my current 1" baffles and will probably use that method.

Also, I have been playing around with the linseed oil. What a nice, easy finish.  I am not doing the main baffles yet because of the above contemplated addition of another panel.

I am listening to the Big Betsys exclusively now before the fest so I have the memory of how they sound before I hear Steve/Bob's version of the same.

Having put them back in my system after listening to my old OBs with the Acoustic Elegance bass drivers for a couple of days, I can safely say that the Big Betsy's actually have more hit in that 100-200Hz range which is pretty intoxicating.  They don't go as low, but you definitely feel them more.

Title: Re: Steve's BIG BETSY Project
Post by Nixxuz on 10/01/19 at 16:31:13

"One thing I see about the FAST 10 is that the Qts is even lower than the Crystal 10 and significantly lower than the F15.  I assume you're intending it for OB?"

Semi-OB. The design I'm currently running is an enclosure with subs that have a baffle that extends past the enclosure, where the FR driver is mounted. I just haven't found a driver yet that gives decent LF extension below 40hz. Might be good enough for many people, but I find the sound "thin". I suppose I could have gone single FR driver in an OB and supplemented with a powered sub, but this is kind of like supplementing with dual powered stereo subs. The single sub works for some people, but I find I can pretty easily tell directional LF, especially when the FR drivers may only put out reasonable response down to say 60-80hz. Bumping the sub to meet that response gives it more directional sound. On the con side, it really makes it hard to sell off old designs when you need to specify that it needs 2 amps to run!

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/02/19 at 02:12:28


We have them done here and doing a dry assembly, mostly so we can stand them up and see how everything fits.







The front feet we made from solid hard maple so that if we went with a clear finish they would match.  

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/02/19 at 02:21:26


We decided not to go with a clear finish, because the plywood is so bitchy to work with, stringy with unpredictable tear out. Also it is drum sanded so once you stain it, you will see ripples no matter how smooth you have it sanded.



I used amber shellac (vs. clear shellac) to seal the baffles before we painted them so I could see what that looked like and it looked like shit. Don't ever try it as a final finish. As a sealer it kicks ass though with only one coat.

Steve



Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/02/19 at 02:49:56




Another view...





Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/02/19 at 02:58:40




The shellac has dried and now the baffles are disassembled and sanded again. Look how yellow the dust is from sanding the amber shellac.

Steve


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/02/19 at 03:13:31




Final picture for today...  getting the first coat of white lacquer on them.  We were able to finish them before dark.  You'll have to wait until tomorrow to see them in white.

Steve


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/02/19 at 03:48:00


As I mentioned a week or two ago, the Big Betsy and Big Betsy Jr., names can not be used when the speaker goes into production, and that we would be changing the names of both baffles.

I'm not going to actually give them a name, but like most of our products, a serial number that stands for something.  Zen Open Baffle, (ZOB) is a classic example.  So these speakers due to the expense to make and the insane level of performance are going to become part of the Zen Master Series of loudspeakers by Decware.  The Zen Master Series Mark will be flown on the front of the baffle below the driver.  On the solid hardwood models it will be engraved.  On the black and white models it will be a decal of the opposite color (white on black or black on white) and then sealed in under the final clear coat.

Here is the mark for the Decware Zen Master Series



The model number for the Big Betsy will be the ZBOB which stands for Zen Big Open Baffle.  and ZBOBJR, for Zen Big Open Baffle Jr.

Making this "budget" plywood model white with the black logo and such is going to be every bit as hot as looking at the solid hardwood models, and as far as I can tell be $1000 less than the hardwood models.  Don't picture plywood painted white with house paint, picture a hi-end automotive finish because that is what it will be.

We learned from this experiment that the plywood model actually took more time to build than jointing solid wood. Somewhat disappointing, but that's the way it is so what are you going to do? We will make the plans available for these so that anyone wanting to D.I.Y. a pair to save money can still enjoy the glorious sound they produce.

I think Dank had the right idea using MDF which would have gone flawless from start to finish, but the bitchy birch plywood just makes it take twice as long and then if you have to fix anything double it again.  You'll have to fix something.  

So there you have it, this is where we are at in the final hours before the fest, with a potentially better looking Big Open Baffle than my hardwood prototype.

Steve






Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/03/19 at 02:31:30


We're making good progress with the pricing... also we have decided that plywood, MDF and any other sheet lumber will not be used.  Instead, to replace the birch plywood we will use solid 8/4 Poplar. Priced next to that will be 8/4 solid Maple, and so on up the ladder of hardwoods. That means if you want them in white or black (or red for Donny) solid popular or maple would be used.

We will have this pair we built on static display during the fest.  Tonight they are waiting for the F15 drivers to arrive in the morning.





If I have time tomorrow I'll take another shot with the F15's installed.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Archie on 10/03/19 at 15:49:59

I hope you'll give them a listen to see if there is a difference in using various densities of wood for the baffles.  Poplar to maple to exotic hardwoods gives quite a large range.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/04/19 at 04:50:42


We will eventually figure it all out, but I predict the answer is going to be:  Good, Better, Best but within a fairly narrow window so on the surface I don't think it's going to make a lot of difference. To the ultra serious daily listener pushing the envelope at every level, then the difference would be noticeable and probably justifiable but certainly not a deal breaker because if you've never heard the exotic hardwood, you'll be tripping on how good the poplar, plywood or even MDF sounds.  Realize this speaker sounds about 3 times better than everything you put up against it, and we're now having a discussion about something that at best would make a 10% difference.

Steve


Title: Re: Steve's BIG BETSY Project
Post by beowulf on 10/04/19 at 11:09:02

Really nice clean design Steve!

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/07/19 at 14:26:05

Some general thoughts about Decfest.  Since they are mostly OB focused, I decided just to put them here.

I was only there for about 22 hours and spent of lot of the time shooting the sh*t rather than in the listening room.  Still, I was able to get through most of what I wanted to do.

As always thanks to Devon, Steve and family for hosting.  The Bar-b-Q pork was delicious, and the beer selection was great.  Dan also made some tasty and smooth pumpkin soup which I was able to sample before I left.

On my list was basically to compare my 1” Big Betsy’s baffles to Steve’s mega baffles.  Evaluate the Crystal 10s, hear the F15s in Randy’s baffles, hear the Alnico version of the Betsy and measure some tubes.  I got most of it done.

As far as my baffles versus Steve’s.....wood matters.  Steve’s baffles produce a very different sound.  I listened to my baffles all week to make sure I had their sound drilled into my head, but it was an easy call.  The extra density makes for a richer, deeper sound out of these baffles.  I also sensed that the mid range was clearer.  Not sure I understand that.  

But here’s the thing.  I was trying to determine if I should double up my baffles to make them 2”.  When I came home and listened, I liked what I heard.  My baffles are more mid-range focused and a little "lighter".   Not that the bass is lacking, but its not as deep and rich as Steve's.  So I am on the fence about adding the additional layer.

We were unable to listen to Steve and Bob’s Big Baltic Birch Baffles to compare.  They had them in the wood shop, but without drivers mounted.

In terms of the Crystal 10s.  I am not sure I got the full picture of these drivers.  I heard them and did not like them at times, and at other times, felt they sounded fantastic.  

On Friday, I heard them in the big cabinets at one end of the room and in the open baffles on the other.  I wasn't crazy about them.  Then, on Saturday, I had some early morning time in the room with just a few people and essentially, set up with close to the chain I have at home - Mac-DAC-Zbit-25th and I thought they sounded really good.  Very smooth and detailed, so perhaps it was the chain on Friday.

As far as the F15s in Randy’s baffles, you don’t lose all that much and possibly gain some bass.  I attributed this to them gaining bass bounce off the floor.  On the downside, the soundstage is not as big or high as with the Big Betsy Baffles.  Some people discussed tilting them a little but
I did not hear them set up like this.

I did not get to hear the Alnico version of the Betsys (again).  These drivers keep eluding me.

The surprise of the fest for me was Randy’s dual driver OBs in his traditional baffle.  It’s a Betsy with a 10” Eminence woofer.  The sound floated above the baffles, had enough bass to keep me interested and perhaps gave the best sound stage of the fest.

Bob’s new HR-1s also sounded good to me.  I love that tweeter and they had plenty of full, low bass.


Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 10/07/19 at 15:19:24



Hi Tom,

Thanks for the kind words about my various speaker offerings .....

I'm very happy with the "baby" 15" baffles and my new two way Betsy & Buck baffles.

One small correction ..... the original Betsy & Buck baffles have a 10" Eminence Alpha driver ..... the ones I brought to the Fest this year are "version II" and use a 12" Eminence Alpha driver.

Details ..... details .....

It was good to see you again. It would be great if more of us lived closer together.

Best wishes,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/07/19 at 15:23:52

Hey Randy.  Sorry I got the size wrong on that one.  Did they get more play later in the Fest??

Also, I am very interested in your he-shed.  Did you detail your build somewhere on the forums???

How far from Cincy are you??

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 10/07/19 at 15:45:32



Hi Tom,

Yep ..... they did get some additional playing time and seemed to be well received .....

A while ago, I posted a thread about my "he shed".
It can be found here.

If you need any specific info, shoot me an email.

I live in Alexandria, KY which is just a few miles across the Ohio River in northern Kentucky. If you are ever in the neighbothood, the red carpet will be rolled out for you .....

Happy listening,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Archie on 10/07/19 at 16:05:11

I'm not surprised that the ZBOBs were popular at the Fest this year.  I decided to put my HR1s back in before storing them and they lasted for one song.  They sounded great but were hobbled by low volume (92.5dB vs ~100dB) and "small sound."  I think my big room just needs the ZBOB bigness.  After listening to the ZBOB for an extended period I had gotten so use to their sound that I wasn't hearing the magic.  It's amazing how fast we set our new normal.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/07/19 at 18:33:26

Apology in advance if this is somewhere already in this thread, but can anyone tell me the outside ring/cutout dimension on the Crystal 10 driver?  I am not seeing a spec sheet on their web site.

Not that I am thinking about building yet another speaker ;)

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/07/19 at 18:35:13

Nevermind, found it on the web site.

Title: Re: Steve's BIG BETSY Project
Post by lazb on 10/07/19 at 19:35:06

Pal, you thinking of upsizing the DNA cabinet to fit the Crystal 10? I love my DNA2s and think the 10s would be wonderful in that cabinet, sized properly. Lii pretty explicit about cabinet volume needed for it. It sounded good in his hollow box cabinet. Most music at DECFEST was played too loud for my liking and made analytical listening difficult.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/07/19 at 20:04:41

For now, I am a committed OB guy.  I have found my woofer (Acoustic Elegance) but I am still seeking the right driver(s) for my mids and highs.

I am not dissatisfied with what I have for highs/mids (Dayton AMT / Tang Band W8-1808) but feel there could be more detail there that I am not getting.  When I heard the Crystal 10s on Saturday morning, I heard details that I haven't heard before.

I also recently sold two Decware amps so I have a little mad money in my pocket.

Title: Re: Steve's BIG BETSY Project
Post by Lon on 10/07/19 at 20:46:18

Joe: regarding 'too loud'--that would have been my guess. I listen less and less loudly as time goes by, what I love most about my systems is how wonderful they sound at moderate volumes!

The ZROCK2 was the final component I needed to have the sound just right when the volume is just right.

Title: Re: Steve's BIG BETSY Project
Post by Geno on 10/07/19 at 21:08:39

Pal, what is your power source for your Acoustic Elegance?

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/07/19 at 21:11:27

Right now the mighty 2 watt 25th Zen.  It plays very well with it.

If I do try the Crystal 10s, given the efficiency differences in the drivers, I will be using a Crown XLS 1002 I just picked up at the fest.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/13/19 at 02:17:31


UPDATE

After studying peoples reactions to the Big Betsy and Big Betsy Jr. baffles during the fest, and after talking with Randy of Caintuck Audio, we came to the realization that A) the Big Betsys are BIG.  Not everyone can do big.  B) The Big Betsy Jr, with the Crystal 10 are a nice size but are lighter in the bass and require a ZROCK2.  The drivers are also nearly a grand more than the F15 drivers used in the Big Betsy.  When you add both of those factors in, the price well exceeds a Big Betsy with the F15's...

We realized that we need a third baffle... the magic bullet, the best of both sort of thing that would actually cost a bit LESS than the Big Betsy, not a lot more.

So this weekend I am prototyping a similar size baffle to the Big Betsy Jr., but with an F15 driver !!!

If this works as well as we know it will, it should be by far the most popular seller of the three models.  Since there are now going to be three models, it changes things.  My previous model numbers, ZBOB and ZBOBJR, no longer make sense.  

I have decided to make the Big Betsy with the F15 drivers   the model ZF15L, (Zen F15 Large)

I have decided to make the Big Betsy Jr, with the Crystal 10 drivers, the model ZC10M (Zen Crystal 10 Medium)

I have decided to make the new baffle with the F15 drivers, the model ZF15M, (Zen F15 Medium)

This makes a lot more sense and leaves room for alternate drivers in the future that will go into either the Large or Medium baffles.



I am making this new "medium" sized baffle 2-5/8 inches wider than the Crystal 10 Baffle as well as a little taller.  This will better accommodate the 15 inch driver.

I am anxious to hear how this compares to the other two as I'm sure you are as well so stay tuned ; )

Steve


Title: Re: Steve's BIG BETSY Project
Post by Brian on 10/13/19 at 04:29:04

I do not understand the sonic effect of the sides being curved, but I wonder if there could be a benefit to making the top edge curved. Either a single curve like the sides, or a multiple curve like a pair of camel humps.

Me thinking out loud again,
Brian

Title: Re: Steve's BIG BETSY Project
Post by HockessinKid on 10/13/19 at 12:53:26

Steve,

I think adding this F15 medium baffle option is a smart decision. I was really wowed by the large baffled version at Decfest. But, the large size and very heavy weight make it impractical for my listening room. The large baffle version is a real statement speaker, along with the Crystal 10 offerings.

My guess is that the medium baffle F-15 will sound superb and be a big hit amongst Decware fans/customers. The fact that all these speakers can be driven loud & clear with a 2 watt amplifier, well that's just crazy in the best way.

Good luck with the new speaker offerings and thanks for sharing them with us at Decfest.

HK

Title: Re: Steve's BIG BETSY Project
Post by HDDR1 on 10/13/19 at 12:53:27

Nice idea re F15 in a medium baffle.  Back to your large plywood baffles for the F15 - how do they sonically compare to your hardwood baffles?

Title: Re: Steve's BIG BETSY Project
Post by Archie on 10/13/19 at 18:26:16

Steve, I'm sure there is a sweet spot between the BB and Rnady's F15 in the Betsy baffle.  I hope you nail it.  Of course, you'll have to go the other way too.  Otherwise you'll never be sure what lives up there!

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/14/19 at 13:59:28

I had some time to sand and put a coat of linseed oil on the baffles. For not knowing what I am doing, they turned out pretty nice.  Still need to do the plugs.  I left the backs unfinished in case I want to add a second layer of wood to make them 2".

An interesting discovery.  When I was installing the supports on the back I did the old knock test on the bottom of the baffle to see how the wood sounded before and after adding the red oak mass that is bolted to the bottom inside lag screws in the picture below.  Then I did it again after and the sound change was pretty substantial.  Much deeper, less ringing.  

Then I listened to them with the 25th and they sounded much closer to what I heard at the fest.  Denser, more full bass for sure.  It just shows you that wood matters and mass matters as well.  I know Steve talked about this in the thread, but to see it have that much impact was a learning moment for me.


Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/14/19 at 14:03:29

Oh, and since I have gone this far, what wax do you recommend?  

I have this liquid was that I bought when I bought my natural finish cherry dining room table which I was thinking of trying on a scrap first, but suggestions are appreciated.

Title: Re: Steve's BIG BETSY Project
Post by HDDR1 on 10/14/19 at 15:59:57

Beautiful work!

Title: Re: Steve's BIG BETSY Project
Post by Archie on 10/14/19 at 16:22:28

Pal, can you post a picture of the backs?

I use Minwax paste wax.  Wax on, wax off!  I love that oiled oak.  BTW, I never wax over oil, just stain.  The oil is the finish and you can always freshen with a light coat.  The oil has its own patina.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/14/19 at 17:16:28

Yeah, I can get a picture tonight.  

I didn't add that much mass.  Certainly not as much as Steve adds.  But it was enough to affect the sound.

If I don't need to wax, I won't.  I like the finish, just thought wax might help it stay that way.

Title: Re: Steve's BIG BETSY Project
Post by Donnie on 10/14/19 at 22:40:24

So now the question is if the sound got better because of the mass or from breaking up the vibrations with support?
Yes I know that it is basically changing the mass but it is also changing how much cantilever the baffle has.
I will ask another question, what if between the baffles and the base there was a layer of damping material? Would the sound change? Maybe better, maybe worse?
I really hate it when I get thinking about things, it hurts my head.

Title: Re: Steve's BIG BETSY Project
Post by Geno on 10/14/19 at 22:42:02

Very nice, Pal.  I love the finish!  Glad the support made that much difference in the sound.  I'm like Archie - I want to see what the back looks like...

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/14/19 at 23:03:49

I am of the opinion now that anything you do to the baffle alters the sound.  I think of it as stiffening the platform the driver moves in AND changing the tone of the wood.

Don’t expect any great revelations on the photo.  I just went to Home Depot and bought some red oak boards.     Chopped them up into four pieces and glued them together.  Then used stainless lag screws to secure them to the bottom of the baffle.

Based on how the baffle sounded before and after. I am not sure I want to do more.  I don’t want to over deaden the baffle.  I like it a little lively.  

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/14/19 at 23:08:37

Btw I also did the highly scientific knock test before and after I re-attached the handles to the top.  Not nearly as much change in the tone but a change none the less.  I think too much deadening of the wood with thickness, mass, weights etc can make the drivers sound too mellow.

With Decware equipment Steve keeps it less warm than traditional tube amps and I want that characteristic to stay.

Title: Re: Steve's BIG BETSY Project
Post by HockessinKid on 10/14/19 at 23:52:34

Pal,

Great job on the open baffles, they look super nice. Enjoy your listening.

HK

Title: Re: Steve's BIG BETSY Project
Post by Archie on 10/15/19 at 00:13:24

Pal, I can't remember what your footers looked like originally but I assume you've got more to Steve's version?  

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/15/19 at 02:46:26


Feeling really good about this medium size baffle for the F15 per Randy's suggestion. This one has a really good size and shape. I like the thickness, and the base is meatier as well. It just has that "rightness" about it's size and shape.  

Also to the point about how plywood will sound, I didn't get a chance to hear the pair Bob and I built as someone bought them before I could finish them. Since I had enough Baltic Birch left to make this medium size baffle I used it. This way I can hear the Birch plywoods effect on midrange timbre and compare it to the harder Wenge and Paduke. Also, this will be THE ONE that most people will D.I.Y. so I'll be able to develop the plans for it and have a working sample.



So far I have one coat of linseed oil on them, which looks really good - actually a lot better than the picture would suggest.



One of the things that make this model different is the offset. In this model the F15 driver rides just 3/4 of an inch above center. That's just enough to prevent ringing*. This also puts the driver a lot closer to the high-mass base so I expect a real solidness to the sound hopefully similar to the large hardwood baffle. Also of note is the close proximity to the base could have a desirable sound board effect to reflect sound upward toward the front wall. That means that you will hear a bigger difference with and without the 2 inch foam absorber that I grew to like on the other two baffles who's woofers are farther away from the base.

*ringing - by that I mean having a symmetrical shape around the woofer would create a ring of high pressure that stands on the boundary of the baffle. That would make the imaging more shifty when you move around.


Steve

Title: Re: Steve's BIG BETSY Project
Post by will on 10/15/19 at 04:15:11

I agree with the rightness of the look Steve. Pleasing and comfortable. Making pots most of my life, when the pots went beyond clay, fire, form, maker, etc.— natural mystery, lively beauty, and function seemed to be reflections of one another...or maybe better put, aspects of one another. When natural and complete enough to enhance daily life, beauty is function.

Can't wait to hear what the medium baffles sound like to you!

Title: Re: Steve's BIG BETSY Project
Post by ScottNC on 10/15/19 at 05:04:24

As always, well put Will, I completely agree they look really well balanced and just appear they will sound good! Steve, I’m excited to hear your thoughts on the sound also. It promises to be an exciting option, what a year in development for Decware.
Best,
Scott

Title: Re: Steve's BIG BETSY Project
Post by Lon on 10/15/19 at 12:22:14

You know, one big takeaway for me from this whole big and medium Betsy unveiling and high praise is. . . Randy has certainly earned, beyond dispute, his DEMIGOD status in the Decware audio world, and it's extending BEYOND in the future will not surprise me.

I'm a solid user for over a decade and into the future of the Steve and Bob radial designs, and would rather spend imaginary or future money on the fullest upgraded HR-1 than a Betsy, but DAMN this Betsy design remains a masterstroke that has born wonderful fruit!

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/15/19 at 13:54:12

I think you would enjoy Bob’s latest offering Lon. Big full sound with even better bass.  

That said, I have been rotating speakers lately given that I got multiple drivers delivered within weeks and I am always amazed when the Big Betsy’s go in.

I hope all three of them continue to create things that amaze me.

Title: Re: Steve's BIG BETSY Project
Post by Lon on 10/15/19 at 13:59:34

I'd be a lot more interested in the Betsy's if . . .

I didn't already have one more pair of speakers than I can use (ERR). . .

And if they would fit somewhere in my house for the two systems I have. They won't unless I were living alone. . . which I don't want to do!

I'm sure I'd love the newest edition of the HR-1s but I can't afford them right now. Maybe one day! I'm happy otherwise, very much so, with the two pair I have.

All praise to the Demigod of Caintuck! He has come into his own. :)

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/15/19 at 14:07:08

As promised, not much to see here, but as I tightened down the lag screws, I could hear the tone of the baffle changing.  I think you can tune the baffles by adding more/less mass to them.



Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 10/15/19 at 15:10:04



Lon wrote .....


Quote:
You know, one big takeaway for me from this whole big and medium Betsy unveiling and high praise is. . . Randy has certainly earned, beyond dispute, his DEMIGOD status in the Decware audio world, and it's extending BEYOND in the future will not surprise me.


Hi Lon,

Many thanks for the kind words ..... but I much prefer the more accurate designation of "the blind squirrel that found the occassional acorn" .....

There is certainly true genius that exists in this world, such as that of your relative who built the amazing instrument played by Jack Mitchener on the Dulcet Tones album you introduced us to.
I play that album on a regular basis and use it as a "demo disk" when someone wants to hear my audio system ..... it's amazing .....

Best wishes,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Lon on 10/15/19 at 15:28:05

You're too modest Randy. You can't shrug of Decware Demigod status that easily!

Glad you are enjoying that disc. I have a few other discs of Tannenberg organs played that I enjoy. And I can still remember pumping a few of the organs as they were played when we traveled to see them as my Dad was researching his biography of Tannenberg, more than fifty years ago.

Title: Re: Steve's BIG BETSY Project
Post by BillW on 10/15/19 at 16:36:26

I really like the look, very clean, “simple” and effective.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 10/15/19 at 16:37:02

Thanks for the look Pal.  That looks more analogous to my footers than Steves in that our's both have heavy stiffeners between the rear feet.  I added the 25 pounds of lead shot as well.

When I do a knuckle wrap test on my baffles I can definitely hear the  pitch change as I run over the rear weights and in and out of the "free wood" zones of different sizes.  My weights were place with the idea of breaking up symmetries and they probably do just that.  

So far, with the various baffles we've built using different materials, thicknesses and now sizes, its amazing how consistently good the general design seems to be.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/15/19 at 19:30:00


Finished the last coat of oil today, and should be able to get some drivers installed this evening.

Steve

Title: Re: Steve's BIG BETSY Project
Post by HDDR1 on 10/15/19 at 19:42:17

Awesome - looking forward to your assessment of the sound.

Title: Re: Steve's BIG BETSY Project
Post by BillW on 10/15/19 at 20:40:49

Nice! Eagerly awaiting your impressions and then of course, how they break-in.  :)

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/16/19 at 02:18:16


Here are a few more pics as they come together...



Last coat of oil.  These things are smooth as a babies ass, such an improvement over my first attempt when I tried to get this look with amber shellac.  ::)

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/16/19 at 02:20:07

 


Side View with the F15 driver installed.


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/16/19 at 02:28:49








Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/16/19 at 02:53:21




So now we wait for the handles...  meanwhile I drug them into the listening room to start breaking in the drivers.

Going from memory, when the original Big Betsy baffle was breaking-in, I can safely say that these Medium Baffles seem to have all the hit and bass of the big ones.  At this stage I can't tell any difference. Once they are burned-in for a few weeks, I will do some A/B tests to figure out what is different. The fact that I will have to "figure it out" should tell you something.

They look beautiful in the listening room. Way beyond my expectations. Also, I was not only able to lift them, I actually carried the first one into the listening room from my shop. I felt like that was probably a poor idea at about the half-way point. The second one I was torn about carrying it in left handed to balance out the pain from the first one, or just using my two-wheeler. I went with the later. So yea, they can be moved around similarly to the Crystal 10 baffles.

I can't wait for the handles to arrive to I can hear what these are actually going to sound like. Then I'll be able to figure out the difference in sound between the baltic birch plywood and the hardwood baffles I made.  

This reminds me of something I've been wanting to mention... during the fest someone grabbed a scrap of Wenge when we were out in the shop and tapped it. It sounded like glass.  A good way to listen to wood, is to size it all the same, preferably flat and wide and perhaps 3/8 inch thick so you can strike it like an instrument. The Paduke is a far warmer tone. Mixing the Paduke and the Wenge may be where the refined magic comes from. In the case of the Crystal 10 baffles, I used white oak which is closer to the Wenge, and then Walnut which is actually softer than Paduke. Point is, contrasting woods are going to have a dramatic effect on how that baffle resonates and where.

Steve



Title: Re: Steve's BIG BETSY Project
Post by HDDR1 on 10/16/19 at 03:12:01

Thanks for the update - good to hear there does not appear to be an obvious sound difference between the large and medium baffle.  Will be interesting once they are broken in.  How many hours do you think you need to log on both the F-15s and Crystal 10s to really break them in do you think?

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/16/19 at 03:37:20


BTW, I agree with Lon about Randy : )



I keep waiting for the dual 6x9 to come out, then we'll all know for sure ;)

Steve



Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/16/19 at 03:39:58


Quote:
good to hear there does not appear to be an obvious sound difference between the large and medium baffle.  Will be interesting once they are broken in.  How many hours do you think you need to log on both the F-15s and Crystal 10s to really break them in do you think?


250 hours.

Steve

Title: Re: Steve's BIG BETSY Project
Post by will on 10/16/19 at 03:46:32

:)

On the medium baffles, nice grain! Nice to hear 1st impressions are so good too. These speakers are still pretty big right? Guessing something like ± 35 x 30?

Title: Re: Steve's BIG BETSY Project
Post by Archie on 10/16/19 at 15:43:42

Steve, it appears you didn't radius the back side of the baffle hole?

Title: Re: Steve's BIG BETSY Project
Post by BillW on 10/16/19 at 16:46:31

Quick noob question: why no tilt back on these and similar style (Randy’s) baffles since often they are fairly low to the floor, even if slight, i.e. 5 degrees?  How does that help or hurt the sound of the units?

No intent to take this thread off track, rather to add some additional information regarding this design.

Appreciate any insights.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/16/19 at 17:12:08


With regards to tilt, remember that there is as much sound coming off the rear as there is off the front.  Firing the rear into the floor or low on the front wall from tilting seems to have more negative effect on perceived image height than would seem intuitive.

Title: Re: Steve's BIG BETSY Project
Post by Rivieraranch on 10/16/19 at 17:14:42

Although there are more knowledgeable persons here than I, it has to do with bass response. When set on the floor, the sound "floats" above the baffles so they don't really need to be tilted. I was there at Decfest when Randy's 15" baffles were lifted. The sound was "higher" but the bass was diminished.

Title: Re: Steve's BIG BETSY Project
Post by ZZuZZaXX on 10/16/19 at 21:14:54

Is bigger better?
I work in a small office and I have an older SE84C that I think should be able to power a version of the Betsy jewels.

What is recommended?

Title: Re: Steve's BIG BETSY Project
Post by HDDR1 on 10/16/19 at 21:37:58

People heard Randy's Betsy speakers w/woofer and his version of his baffles with the F-15s at Decfest and everyone was impressed.  Randy's speakers on his Caintuck Audio website are much smaller if size is an issue.

Title: Re: Steve's BIG BETSY Project
Post by ArtMan on 10/16/19 at 22:06:33

I want to add Randy to legend status at Decware. I ordered one of his Lii 15 baffles which coincided getting some of Steve's speaker cables. Other than doing a little more tube rolling of my driver tube, I've mostly been listening a lot and letting them break in. They look modest but they are magnificent sounding and I'm just enjoying the hell out of them. Being reasonably light and small, if you can find a 15" driver small, they are very easy to move around. I am as happy as a clam.

Title: Re: Steve's BIG BETSY Project
Post by Brian on 10/17/19 at 03:49:43

Steve,
Using a shelf or boxlike structure in back instead of open feet or open legs, was this influenced by the box on the back of your original Open Baffle speaker?

Brian

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/17/19 at 14:19:25

I have posted about getting the Crystal 10s on the Palomino Audio thread but I have a couple of Betsy Baffle thoughts.  

I currently have the Crystal 10s in my three-way open baffle with the AMT (disabled), the Crystal 10 and the Acoustic Elegance LO15 woofer.  I have it in this configuration for break in and while I make a baffle.

In this setup, the listening experience is completely different from the Big Betsy’s.  For one, it leans more towards the “you are there” vs the “they are here” sound.  Both presentations are good, but right now I prefer the Big Betsy.  Perhaps because its new to me.  This could change if I migrate to a Big Betsy Baffle.

Also, I was actually concerned in listening to the Crystal 10s during break-in. I expected some initial edge but after 40 hours I thought it would subside more.  It didn’t so I looked at the 25th and saw that I had it in the higher bias setting.  I like it this way with the Big Betsy’s.  Once I flipped to the lower bias setting, I noticed that I ran the volume closer to where I run the Big Betsy’s and everything smoothed out.   This was the last thing I did before I called it a night so I will spend some more time with this setting tonight.

The Crystal 10s are definitely a more sophisticated driver but I feel more engagement with the Big Betsy.  The sound popping off the baffle/tactile feel and the “they are here” presentation brings you more into the music.  While the bass goes nowhere as low on the Big Betsy’s, it has more pop. I have played with the crossover point for the LO15s and have closed the gap but the Big Betsy’s still hold the edge.

I am not out to choose one speaker over another, but the jury will be out on the Crystals until I get them in a medium to big Betsy shaped baffle.

Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 10/17/19 at 15:02:10



Rivieraranch wrote .....


Quote:
Although there are more knowledgeable persons here than I, it has to do with bass response. When set on the floor, the sound "floats" above the baffles so they don't really need to be tilted. I was there at Decfest when Randy's 15" baffles were lifted. The sound was "higher" but the bass was diminished.


Yep ..... you nailed it.
The "received wisdom" states that the primary driver of a loudspeaker needs to be at ear level of the seated listener. While there may be some benefit to this with many speakers, it appears that full range drivers in open baffles are not "captive" to this rule.
By having the drivers closer to the floor, it couples the floor to the speaker and enhances the bass and lower midrange. You can actually "tune" the frequency balance by tilting the speakers by varying degrees.

I know that quite a few of my customers do tilt the speakers back in their listening rooms ..... YMMV.

In my listening room, I am content with the height of the stereo image with the baffles sitting flat on the floor ..... but it's a matter of personal taste.

Best wishes,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Randy in Caintuck on 10/17/19 at 15:14:55



Hi HDDR1 and ArtMan,

Many thanks for the positive comments .....

As I mentioned in a previous post, we are currently living in one of the "Golden Ages of audio". There is so much good sounding audio equipment available and a second mortgage on the home isn't needed to own a very satisfying audio system.

I'm very happy to be a small contributor to this situation and the fact that these speakers work well with all of the Decware amplifiers (including the low powered ones) has made my small "retirement hobby / business" a lot of fun for me .....

Best wishes,
Randy


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/17/19 at 21:56:43


EPIPHANY:

About the handle, vibration, and how this baffle works.

So today the handles came in for the medium baffles I just completed. I have been listening to them for a couple days without the handles, struggling with the break-in of the new drivers. In that state the speakers sounded somewhat congested and had a bass peak I didn't care for.

As I've noticed on both other baffles, when I place my hand on the handle, the sound changes. It gets softer. Today I realized what is happening as I did it over and over. My heavy arm is a vibration sink connected to the handle which is connected to the baffle. That means the baffle goes from live to dead which would be similar to creating a baffle made from two stiff layers with a soft sandwich in-between.

Without having built one to see for certain, I am 90% certain it will suck. When I say putting my hand on the handle makes the sound softer, I mean that immediacy goes away, sounding more like a conventional speaker than a live experience.

So as I have been suspecting all along, it is the stiffness and mass of the baffle that controls the energy in it. That energy is released into the air literally as fast as it is created. There is no phase angle discrepancy that I can hear. With my hand on the handle, the baffles ability to move in phase is ruined and the sound becomes softer and less distinct.

Also, the bass peak that has been difficult to deal with over the past two days is gone, replaced by an ultra tight hit.  This is solely due to the cast iron handle.

The DIY plywood version medium baffle with the F15 driver sounds very close to the hardwood, enough so that you would have to A/B to hear it.  So this should be encouraging to the DIY speaker builders who do not have planers and jointers.  

With these baffles, that I can lift without much trouble, I can now move to spikes and see if that ruins the sound or makes it better.  My floor is concrete with carpet.

-Steve


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/17/19 at 21:59:07

Archie,

I didn't radius the back, because the thickness is just shy of 1.5 inches whereas the large ones are just proud of 1.75 inches.  I figured on this baffle with that distance it wasn't going to make enough difference to fuss with.  I'm sure the DIY builders will enjoy not having to buy a carbide 1 inch round over bit for their router!

Steve


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/17/19 at 22:01:46


Quote:
Steve,
Using a shelf or boxlike structure in back instead of open feet or open legs, was this influenced by the box on the back of your original Open Baffle speaker?

Brian


It was influenced by Randy's original design.  If you were to remove that thick base (2x thicker than the baffle thickness), the sound would be ruined.  It and the handle placement are two of the tricks that make these speakers work.  You'll notice I don't skimp on the mass of this base, and there is a reason for it ; )

Steve

Title: Re: Steve's BIG BETSY Project
Post by Geno on 10/17/19 at 22:09:22

Steve, how much difference do you think the handle material makes?  I ended up with 7" long handles that I got at Home Depot. They are not solid metal, but made out of some type of composite material that can be broken if hit very hard. There were a few in the stack for sale that were already broken in half.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 10/17/19 at 23:57:11

Geno,

Pal and I bought from this ebay seller.  I paid $13.50 and I think Pal got his for $12 something.  They are the same as what Steve uses.  They come in the white so you can paint or something.

https://www.ebay.com/itm/Pair-of-9-Large-Rustic-Handles-for-Barn-Door-or-Gate-Pull-from-Antique-Design/173389877363?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/18/19 at 00:02:21


Geno, we will wait for your report to see if you notice the difference.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Geno on 10/18/19 at 00:34:55

Thanks very much! I’ll get em ordered.

Title: Re: Steve's BIG BETSY Project
Post by Brian on 10/18/19 at 02:32:46

I thank you, Steve for the answer on the shape of the base. The nuances of this speaker fascinate me. Little things I would not have suspected make such an important difference to the sound.  As you said: signatures of the Gods.

Brian

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/18/19 at 04:42:15





They ended up being 35-1/2 tall.  That's one inch taller than the Crystal 10 baffles.

The width is 29-1/2 vs. the Crystal 10 baffle at 26-1/4.

Radius of the arc ends up being 29.92 inches.  Top and Bottom flats are 17-1/2 inches.  Center of woofer is 18-3/4 from the bottom.

The sound is really coming into its own today with the addition of the handles and the additional 24 hours of play time...  probably getting close to the 75 hour mark.  

From a casual standpoint I can already sense the sound is like the big baffles. So much so that I have forgotten what the big baffles sound like if not like this. The differences must be fairly subtle.  We'll see what happens when we get in the sweet spot and do some real listening probably sometime next week if they continue to break-in at the present rate.

Steve

Actual plans will be available on the site once the final set is drawn.


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/18/19 at 05:08:50


I agree, the nuances are fascinating.  The shape, the density of the wood, the types of wood, all behaving like a musical instrument not a speaker box.  The baffle is extending the wavefront of the speaker cone to match the exact size and shape of the baffle, just the way a musical instrument does, like a Piano, or violin.

Title: Re: Steve's BIG BETSY Project
Post by dank on 10/18/19 at 12:49:32


Quote:
I agree, the nuances are fascinating.  The shape, the density of the wood, the types of wood, all behaving like a musical instrument not a speaker box.  The baffle is extending the wavefront of the speaker cone to match the exact size and shape of the baffle, just the way a musical instrument does, like a Piano, or violin.


So do you think this might still apply if you put sides and a back on the baffle (and maybe a port?)

Bought my first Grizzly tool thanks to workshop envy inspired by Decfest 2019.  Instead of upgrading my drill press, which I use all the time, I bought a mill.  Its being delivered in 3 days.
https://www.grizzly.com/products/Grizzly-7-x-27-1-HP-Mill-Drill-with-Stand/G0704


Dan

Title: Re: Steve's BIG BETSY Project
Post by Lon on 10/18/19 at 15:08:39

I find similar nuances when woods are used as tone woods for stringed instruments, both acoustic and electric, . It can take time to differentiate, but there.

Title: Re: Steve's BIG BETSY Project
Post by ArtMan on 10/18/19 at 21:06:52

Palimino,

the ability to feel the bass is one of the aspects that I love about the 15 inch Lii Audio driver. It gives the feeling of aliveness, a you are there aspect that I haven't been able to get with a smaller driver. Listening to an acoustic bass, it has a tactile feel that I only get in a live environment. I've gotten very sensitive to vibrations and the Big Bestys let me indulge in it.  I still find myself switching between different driver tubes for different aspects of sounds. I'm still finding myself coming back to the Matsushita 7dj8 although I also like a mid 60's Reflector 6H23P-EB for a brighter sound.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/19/19 at 02:02:40

I was running the more aggressive bias setting and a more aggressive input tube with the big Betsy’s.  Both amplified the pop of the F15 driver.  For the last 5 days I have been listening the the crystal 10s and went to the lower bias setting and a less aggressive input tube.

With some hours on the crystal 10s and the less aggressive setup I am starting to hear the magic of the crystal 10s.  I will likely keep both speakers because of what they each do.   But the simplicity and the musicality engagement of the F15 driver plus the cost make it the easy favorite...for now.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/19/19 at 02:19:29


Testing the low bass tonight...through the treble - pretty incredible actually.  Here is the test material:  

https://youtu.be/rLYRfHjZIy8

https://youtu.be/bIOQ2Fwto8k

https://youtu.be/O4HEWyEh0BQ

If you can get a concert grand piano to sound real, you've got it.  As I listen to it on this system it again seems impossible that both a 2 watt amp and a smaller open baffle could do so well.  

Steve



Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/19/19 at 03:18:03

And of course you know where this leads...

https://youtu.be/mrB8IthgoRQ

Here is a comparison of three of the worlds best grand pianos, A Steinway, A Fazioli and a Bosendorfer.  I know the speakers are at a point where they are more than worthy of rendering the comparison being driven by the 25th Anniversary Zen Triode... so let's just see which one sounds best shall we?

What I am hearing is the Steinway is beautifully disciplined and soft, almost boaring.  Its midrange and top end sound too much like the pianos I played when I was young. I now realize had I got to play a Bosendorfer I would still be playing it 50 years later, today.

The Fazioli has a wonderful lower mid bass that I really like, but otherwise the entire mid band and top end shorts me out.  

The Bosendorfer is the best sounding piano I've ever heard. It has glorious texture, tone, timber with the most spiritual top end I've ever heard, and if I could have one I would probably trade my stereo for it, and start making music instead of listening to it. So it would be in all of your best interest to keep such a compelling distraction away from me, because I would literarily just set at it and compose music until I die.

These three pianos have completed different sounds, so what would be your favorite?  I can tell you that these medium and large baffles make a grand piano feel completely real.  No other speaker quite does this so well.

Happy listening.

Steve

P.S.  Despite the choice and reasoning of the guy who played the pianos, going only on the sound, I stand firmly by my opinion.  Also, to hear what two of these pianos sound like in a large space, played by someone else, to gain a wider perspective, here is another comparison video: https://youtu.be/T2GYYV8JSqM. Again, the sound of it just melts me.  The other two pianos are nice, but not in the same league.  It really is fascinating how something like this could create such a strong opinion.  Hehe, I know sound is subjective, but to me the difference is pretty massive while others will choose what I hate.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 10/19/19 at 18:09:51

I only watched the 35 seconds, so far, but a massive difference in the pianos is their age.  The Steinway and Fazioli are new while the Bosendorfer is several years old.  Pianos get better with age and use -- up to a point anyway.  This comparison may be like comparing green tomatoes with vine ripened.

Save your money for now Steve and do a comparison of more similarly aged pianos.   :D

Title: Re: Steve's BIG BETSY Project
Post by Lon on 10/19/19 at 18:45:48

It's true about the age of the pianos. My favorite piano I've played in person is a very old Steinway that an in-law had. I do like Bosendorfers but haven't played one in person, though I've heard them in person. I have a cycle of Beethoven piano sonatas on SACD performed on a Bosendorfer recorded very well that I really enjoy (even though they were composed on an earlier form of piano, and especially not with the extra octave the Bosendorfer has on the keyboard).

Title: Re: Steve's BIG BETSY Project
Post by Archie on 10/19/19 at 18:50:06

A friend of mine learned to tune pianos at the NY Steinway factory.  He told me stories from the technicians there about how the pianos didn't sell during the Great Depression and just sat.  The technicians would occasionally go over them and fix any minor defect that occured with time.  As a result, those were the greatest Steinways produced and were responsible for Steinway's reputation as the best piano.

I'm sure there is some truth to this tale.

Title: Re: Steve's BIG BETSY Project
Post by Lon on 10/19/19 at 19:10:52

I would believe it. When my first wife's aunt passed we were offered another Steinway in that family, a player piano from the 'twenties, that was in her home in Chicago since she was a kid. I wanted it so bad, but had to agree with my wife there was nowhere we could put it in our small home in Austin. I bet that was a fantastic instrument as both a player piano and to play personally.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/20/19 at 01:47:29


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/20/19 at 01:57:28


As you can see I'm getting really close now! The web page is 90% done for the model ZF15L (large) and I am pleased to say that we will be offering them in your choice of 16 different 2 inch thick solid hardwoods! The type of wood is what determines the price. On the low end with shipping they will land right at $4000 for the pair! On the high end with shipping they will land right around $6000 for the pair, such as the model shown above.

I hope to have this model online for orders next week sometime!!!  

The ZF15M (medium) will be exactly the same price, but will be able to ship for less. So far as I can tell the basic performance of the two sizes is nearly identical, so just go with what fits your room best.

Steve


Title: Re: Steve's BIG BETSY Project
Post by Showme on 10/20/19 at 16:22:32

Great photography Steve!

Title: Re: Steve's BIG BETSY Project
Post by Archie on 10/20/19 at 17:55:06

Had I not built a pair of these I'd be astounded at the price.  But they are deceptively complex to build and given the price and quantity of wood needed, c'est la vie!  Every time I see these beauties I'm tempted to order up some 8/4 hickory and build a better looking set than my Darth Vader pair.   :)

Title: Re: Steve's BIG BETSY Project
Post by ScottNC on 10/20/19 at 18:48:56

Great photo Steve, I’d love to see a medium pair in those same woods. It sure would be fun to live with those and my DNA2’s, a nice custom silver wired speaker selector by DecWare and a guy could never leave the house!
Very exciting to say the least.
Best,
Scott

Title: Re: Steve's BIG BETSY Project
Post by Lon on 10/20/19 at 19:19:34

Beautiful. Those things are GIANTS. I couldn't get them to work in any of the rooms I have. But they look wonderful and I'm sure sound even better than they look.

Title: Re: Steve's BIG BETSY Project
Post by Brian on 10/20/19 at 22:42:40

My choice through my $35 computer speakers (never having played a piano) was easily the Fazioli. Here in this room, that was a sweeter and much more emotional sound. I thought perhaps the hammers were too soft in the treble and were therefore damping the overtones. It may be they were dressed that way on purpose knowing they would compact from several hours of beating against the strings.

I wonder how much of my preference being different from yours is based on your superior knowledge of proper tone from having actually played piano when I have not, and how much is the difference in you using high fidelity speakers and amps and me using speakers I like, but in a lesser league, and no tube amp.

Comparisons are always fun.
Brian

Title: Re: Steve's BIG BETSY Project
Post by Brian on 10/21/19 at 00:33:54

For me, this may be the most beautifully toned piano I have heard that reviewer play.
https://www.youtube.com/watch?v=KFSX79E6pd0
1907 Schiedmayer Grand Piano

Add this https://www.youtube.com/watch?v=i9L6VUV9dW8
Wilhelm Schimmel  Baby Grand  wonderful rich tone

Brian

Title: Re: Steve's BIG BETSY Project
Post by ZZuZZaXX on 10/21/19 at 14:19:24

$6000 per pair?
OUCH!!
I bet they sound amazing, though.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/23/19 at 04:21:40


I have more time on the ZF15M baffles that I made from Birch Plywood.  The reason for making these was to make sure this smaller size as well as a DIY version of this is actually going to be sonically viable.  Now that the speakers are past the initial break-in I can safely say they sound great, and so I'll be making a pair from solid hardwood next to be photographed for the web site.



That means this pair will be for sale in about a month to anyone wanting to audition them in person and take them home with them.

Steve

-SOLD-

Title: Re: Steve's BIG BETSY Project
Post by mito on 10/23/19 at 10:37:56

Hi, I´m new at this forum and i have follow this project with big interest.I´m big fan of open baffle speakers and since  i have F15 drivers on the way a project like this would be great. I would gladly phurchase these birch plywood baffles but since i`m living in Sweden the cost of transportation and with that custom clearance would raise the total cost a lot. You did mention earlier about a DIY version. Would it be possible to purchase the drawings for ZF15M baffles?
Kind regards
Michael

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/23/19 at 14:43:26

These look great Steve.  The smaller size should surely expand the market.

I also appreciate you sharing your findings on material, bracing, footer, etc.  I believe these concepts carry over to other designs.  I have two other pairs of open baffles and I will likely bring some of this technology over to them.  Just yesterday I was looking at the bottom of one pair and thought to myself I am giving up bass response by not having it properly weighted/braced.

No brainer alert!  If you have a two watt zen and want to hear fully what it is capable of, buy (or build) these.

Title: Re: Steve's BIG BETSY Project
Post by BillW on 10/23/19 at 17:24:36

Steve, ditto what Pal just said.

Though I am coming from it another direction, once I have my DIY version of these together I expect I will be reaching out to better understand which version and options of the “two watts” will serve my and my listening goals best.

Just sayin’... :)

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/23/19 at 17:31:10

Buy the 25th!

In the words of Ferris Bueller  "It is so choice. If you have the means, I highly recommend picking one up."

Title: Re: Steve's BIG BETSY Project
Post by JOMAN on 10/23/19 at 23:23:40

Second Pals “Buy the 25th!”.

I’ve had the SE84UFO2 and as good as it is... no contest, no comparison, the 25th is true reference league.

Title: Re: Steve's BIG BETSY Project
Post by BillW on 10/24/19 at 00:12:11

I’ll have to strongly look into that as an option for my household, bunch of enablers you fellas seem to be (lol!).

Title: Re: Steve's BIG BETSY Project
Post by lazb on 10/24/19 at 00:19:54

Not enabling, BillW, trying to save you some money in the long run! Really!!!

Title: Re: Steve's BIG BETSY Project
Post by Archie on 10/24/19 at 00:38:56


Quote:
...bunch of enablers you fellas seem to be...


No, an enabler would be telling you that you need a pair of them to run as monoblocks at 6W!   ;D

Title: Re: Steve's BIG BETSY Project
Post by BillW on 10/24/19 at 00:47:08

;D ;D ;D

Title: Re: Steve's BIG BETSY Project
Post by Geno on 10/24/19 at 04:49:59

Steve, Archie and Pal,

I got the cast iron handles today, put them on, and am very pleasantly surprised with the results. So much so, that I’ve been listening to music for 3 hours straight. I keep listening to music I know well to listen for the improvement. That fact that I can compare before and after the handles has been a revelation. Hard to believe that they could make this much difference. I guess that ‘More Focused’ would be the best description. I’m trying to understand the science of it. Explanations?

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/24/19 at 12:40:13

Randy is an alien :)

Title: Re: Steve's BIG BETSY Project
Post by Geno on 10/24/19 at 13:27:15

I think so. He and Steve both come from a galaxy far away😎

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/24/19 at 14:15:27

Seriously I think the baffle in an integral part of the sound reproduction and you are tuning it.  More weight/stiffness on the bottom equals better bass output.  You don’t want to add too much up top but just enough to impact the mid/treble.  The handle does that.  I suppose you could measure this to be sure but I heard it both with my own baffles and Steve’s on the bottom end. That dense wood and dense base impacts the sound.  It was not subtle.   I also could hear the impact of the handle.

One thing I wanted to do at the fest was get my face close to his baffle to see what kind of wave it was putting off compared to mine.  I forgot to do this.   I’m guessing Steve’s puts off a lower frequency.

One thing I can say is Steve’s baffles put out a richer deeper sound while mine are more lively.  After the fest I almost wondered if the Zrock was running on his big Betsy’s when I heard them but looking back I heard them several times and heard the same thing each time.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 10/24/19 at 15:53:43

I don't hear the stark difference with the handle that you guys are hearing.  Not sure if it's the baffle material or the brass weights I placed on the back of my baffles.  Or just me.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/24/19 at 15:59:43

Archie, I would guess you have tuned your baffle in a different way - with brass weights.  

I also think MDF vibrates differently than Baltic/hardwood and gives off a different tone.

Title: Re: Steve's BIG BETSY Project
Post by Dominick on 10/24/19 at 16:59:09

I was watching a video review of the Tannoy Autograph mini from Upscale Audio.... and they talked about the construction of the speaker.  In those speakers they use a combination walnut over birch.  The density of the wood absolutely plays a critical role in the speakers tone.  Hers the link of the review...

https://youtu.be/JR7pGgbKjag

Fast forward to like 4:54 where he talks about the construction.  

While expensive...I really love the look of those monitors.  Unfortunately they are only 85 dB and with me looking to buy the 25th Zen amp, they probably wouldn’t cut it...unless they were strapped into mono.    

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/25/19 at 02:21:51



Quote:
One thing I wanted to do at the fest was get my face close to his baffle to see what kind of wave it was putting off compared to mine.  I forgot to do this.   I’m guessing Steve’s puts off a lower frequency.


Actually the thicker it is, the stiffer it is and the stiffer it is, the higher the resonant frequency / harmonics will be.  My guess is that the farther away from the bass frequencies you get the resonance, the better the bass.  And the stiffer you get the baffle, the less the woofer frame moves, the better the bass.  And as the mass goes up, the better the speaker couples to the floor.  Speaking of that, I think someone in the DIY community should bolt a pair to the floor and see how that sounds compared to the speaker just setting there on it.  ; )

To test that theory, I once put a woofer in a styrofoam baffle that was 1 inch thick and flexible.  There was zero bass.  The baffle was 4 x 4 feet.  

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/25/19 at 02:24:16


Tonight I have started glueing up a solid cherry pair of ZF15M baffles to replace the plywood ones!

Steve

Title: Re: Steve's BIG BETSY Project
Post by Vooraphile on 10/25/19 at 08:10:45

This OB project going on with Decwarians are so happening..
I couldn't stop the temptation to build one myself..
I have a pair of Alnico 8" full range, I wonder is there any info I could get on the baffle dimension for this size..

Thanks.

Title: Re: Steve's BIG BETSY Project
Post by Palomino on 10/25/19 at 15:14:23

Interesting Steve.  Somewhat counter intuitive but I get what you are saying.  I wish we could have had two or three of these baffles at the fest and the time to listen to all of them.

Title: Re: Steve's BIG BETSY Project
Post by Archie on 10/25/19 at 16:04:10

I can see where a baffle with a low natural frequency would/could cancel the movement of the driver moving at similarly low frequencies.

Bolting to the floor might be an interesting exercise but I suspect that the relative mass of the baffle/driver combination is so overwhelmingly bigger than the mass of the moving cone that no difference could be perceived or measured even if the floor contact were to be frictionless.

Title: Re: Steve's BIG BETSY Project
Post by Brian on 10/26/19 at 03:03:13

Hello Vooraphile

On Randy's page http://www.caintuckaudio.com/
He says:  "The standard dimensions of the speakers are 22 1/2" high and 18" wide - the base is rear mounted and 12" deep."

This is for an 8 inch speaker.

Randy could probably answer questions on his forum page https://www.decware.com/cgi-bin/yabb22/YaBB.pl?board=randy

Brian

Title: Re: Steve's BIG BETSY Project
Post by Vooraphile on 10/26/19 at 05:55:37

Hi Brian,
Thanks for the info.. I shall check with Randy.


Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/27/19 at 01:49:16



Quote:
Hi, I´m new at this forum and i have follow this project with big interest.I´m big fan of open baffle speakers and since  i have F15 drivers on the way a project like this would be great. I would gladly phurchase these birch plywood baffles but since i`m living in Sweden the cost of transportation and with that custom clearance would raise the total cost a lot. You did mention earlier about a DIY version. Would it be possible to purchase the drawings for ZF15M baffles?
Kind regards
Michael


Welcome to the forum!  The plans will be available on the web site once the web page is up and a professional set of plans is drawn.

Meanwhile, here is a PDF file of the plans I drew to give to a professional who can then draw the plans ; )


https://www.decware.com/newsite/ZF15Mplans.pdf


Steve


Title: Re: Steve's BIG BETSY Project
Post by Donnie on 10/27/19 at 01:57:37

That drawing looks workable to me.

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/27/19 at 02:05:27

As mentioned I have started a solid Cherry pair of the ZF15M baffles...  

These I am making from some really old stock of cherry. It was pretty rough, some of it full of worm holes so it is taking some time to puzzle it together in a symmetrical way so that the pair match.




Notice how the board widths vary.  In this case it goes from about 2+ inches to over 10 inches.  What you don't want is boards that are all the exact same width... The more variance there is between the board sizes, the more re-distribution of energy there is throughout the baffle. It's important to keep energy continually moving - as in - changing locations. If it stalls and creates a standing pattern (wave) you will hear it, and that is bad.

I'm pretty sure plywood has this covered when you look at the variety of crap they sandwich between the top and bottom ply, so no reason to panic in the D.I.Y. camp if you plan build one yourself from plywood.

When you factor in what I just said, with the radius sides, AND the 15 inch cut-out for the driver, there is constant change via radius in the shape which also redistributes energy into a beautiful and benign pattern so completely different from a square board, it's really apples and oranges.  Or perhaps more like truffles and turds.

Steve



Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/27/19 at 02:28:06





Cutting the radius... now that I have a pattern of the curve, I don't need to create the giant board to swing the arc, and I can just pattern cut it. Never liking to do anything the same way twice until I've figured out all the possible ways, this time I am using a 1/4 inch up-cut spiral bit.  There is half as much sawdust as a result vs. the 1/2 inch bit I used on the Wenge.

And no I didn't vacuum everything up for the picture... with this smaller bit the dust collection is about 98%.

Steve

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/27/19 at 02:38:40





There is nothing quite like the precision of a router.  The crisp perfect edges really get me off!

Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/27/19 at 03:10:24





I decided on this model and all future F15M hardwood baffles, that I would do a radius in the front, just like I did on the Crystal 10 baffle. I think this will look better, and probably sound better as well. It makes installation a lot safer because you are installing screws from the back rather than the front. This eliminates running a screwdriver bit through the surround of the speaker during install. Also, the F15 drivers have a gasket on the front that is properly utilized this way. And, best of all, you won't see the frame so it shouldn't matter what color it is.





This will be my personal pair of F15M baffles.  The wormholes are probably pretty rare, and this was my fathers stash of cherry which he himself cut down and milled, so I am finally able to turn that forgotten part of his life into a 500 year pleasure transducer.


Steve













Title: Re: Steve's BIG BETSY Project
Post by Steve Deckert on 10/27/19 at 03:25:02


As I get more into working with hardwoods, I have noticed that everything takes forever. Today I worked 7 hours straight in the shop and all that happened was getting both of the glued-up panels sanded, and one of the two completely cut out. You tend to think that that's pitiful... but here's the deal...

The solid hardwood thing that you made well, as best you could, will last for 500 years. If it's well taken care of it will last for over 1000 years. This is of course assuming it isn't ugly and doesn't suck. In that case it won't last because someone will burn it. So lets assume it's beautiful and no-one wants to through it away, and it lasts for 500 years... how long it took you to make it is insignificant.  Here's why:

Took you 32 hours to make it.

500 years is 4,380,000 hours. That means that the time it took it build it was 0.0000073% of the time that it actually lasted.

-Steve


Title: Re: Steve's BIG BETSY Project
Post by Bottlehead on 10/27/19 at 05:27:03

Steve,

That's what I tried to impress upon the subcontractors who came to work on my properties. Once in a while, a guy would come along, understand it, and buy into it. But not many. Most just wanted to get the most amount of money for the least amount of work, cutting corners all the way. And the fact that they were working on something that could last for a hundred years plus made no impression on them. They didn't have any vision, or any pride in their work. Fortunately for all of us, you do.

Thanks for taking us all along with you on your journey.

Randy

Title: Re: Steve's BIG BETSY Project
Post by Archie on 10/27/19 at 18:13:07

Too bad the drivers would be dust by then.  So, is the Decware Lifetime Warranty in effect for all that time?   ;)

Steve, minor typo on the plans, I think the 12 3/8" should read 15 3/8".

Having built my baffles out of BB that has regular strips of about 2 inches, I naturally take exception to the proposition that random sized boards are needed.  This might make sense if different woods are used, hence, different densities, but I can't see why give the same wood, widths of the strips matter.

I see that you have some sapwood at the edges.  When confronted with cherry I often stain first to pull the color together.  Otherwise it can look a bit like a zebra.  Linseed on cherry is a true thing of beauty!  An alkaline wash will darken the cherry and make it look 200 hundred years old.  It's the same effect as when you are pouring concrete near a redwood deck and you step on the deck and leave a dark footprint due to the alkaline staining of the RW.  (Just a few random thoughts.)

Title: Re: Steve's BIG BETSY Project
Post by mito on 10/27/19 at 19:48:19

Steve, it`s great.
Thank`s a lot.
Looking forward to follow this forum and the products of your`s.

Michael

Title: Re: Steve's BIG BETSY Project
Post by BillW on 10/27/19 at 21:29:05

Steve, that Cherry looks, well, uhm, absolutely “Cherry”. Beautiful, beautiful pieces there! Just wow.

Title: Re: Steve's BIG BETSY Project
Post by dank on 10/27/19 at 22:23:42

I'm cutting down a neighbor's dead tree for firewood, Poplar I think, that's about 36" in diameter, BIG tree.  I keep wondering what a slice of that trunk would sound like as an open baffle.  It's close to the right shape.  Couple of slices 2-3" thick plus a 3rd slice 4" thick cut in half to form 2 bases...humm  Too bad its Poplar and not all that pretty.  Too bad I have