I tried to engage in this thread, but all the pics from last year are gone.

'course, I was gone last year, too.

Nice to see you back on the forums.  ;)

We still on for this Sunday?

I built a solid box for my sub experiment this last weekend.  3/4" MDF 19.25X19.25X20.  Well braced, double front baffle.  Weighs a ton.

But I must say I am happy with the result.  The Augies are a fantastic driver, but they fall off under 50hz.  This sub definitely fills in and makes certain music more enjoyable.  I was surprised that it lends definition to the bass in a lot of songs.  But you can feel it on those with the low low bass.

I was also pleasantly surprised at how well it integrates.  I have the crossover set for about 45hz and it really blends.  Raven gave it a listen and felt is was just a bit off and that I should experiment with the position a little to get it the last 10% or so.  I literally put it where I had room so I haven't played with it yet.

They recommend 1000 watts to drive the 15" driver but I am more than adequate with a Dayton Audio 250.  I'll experiment with more powerful amps, but so far so good.

P.S. Eric was right again.  

Here is the 8" driver for you.
https://www.parts-express.com/grs-8fr-8-full-range-8-speaker-pioneer-type-b20fu2...

These things are stupid good for $12.
My latest build is a transmission line using 2 of these in each box. I'm having a hard time putting my OB's back in. It is kind of silly fun.

For fun, I created a template that allows me to put my Silver Flute 8" 4 ohm drivers into my OBs in place of my Tang Bands.  These are the drivers in the DM 945 speakers.

Sensitivity matches up with the AMTs and I am using the same cap value which crosses at 12K.  Basically this is the 945 sound in an OB platform except a dipole AMT tweeter (which I love for conveying the room sound).

So far, I am impressed.  A little warm, but very nice.

In checked those out Donnie.  I especially like the example where the guy put a bunch of them in a cabinet for his car.  

But they don't match the efficiency of the AMT (94db) and that would require more of an xover and I am trying to keep this to a single cap.

I'll keep looking but this driver sounds pretty good.  I may also try the 945 tweeter but it's not dipole.

I'm not sure I can take any more of a beating.

I will be home around 6:00 if you want to swing by.

You could also pick up the tape deck which would give you an excuse to swing by Steve's. (although I do think he will keep this close to the vest)

There has to be another solution. Especially if you're running those AMT tweeters. We need to find a fast driver the compliments them well.

Pal...check out the new 8in drivers from Acoustic Elegance (94.6dB).  Note: I am sending you their Facebook page vs. website, because I remember reading the website was hacked recently.  

Also worth noting, if you expand the comments for the new drivers they are working on a finished open baffle speaker (similar to the PAP design).  Their dipole woofers get good reviews and are used in the higher end Spatial Audio OB's, so could be an interesting option for the non-DIY crowd.

https://www.facebook.com/aespeakers/

Pal...cheaper than the Voxativ experiment I suppose, but still not cheap in the absolute.  Also, it also seems he had a different driver in mind for the AE PAP, so that could be worth a discussion too.  I get the sense that all the drivers are handmade to order, so...

Separately, I was wondering if the Leonidas crossover from the PAP might be helpful as an experiment to dial in the TB in your baffle (or any driver for that matter), but it doesn't look like they offer the crossover as a component anymore. It's possible they might configure one for you though.   I like that it's user configurable with a screw driver and new components (caps, etc).

I might send a note to AE to see how serious he is about the OB project.  

Have fun.

This guy on Audio Circle replaced his Leonidas and made a set of custom crossovers for his Pure Audio Project Voxativ AC-1.6.

Here is the parts list:

• 4 pcs of Jupiter 15uF HT Flat Stack and 1 pc Jupiter 8uF HT Flat Stack to = 68uF.

• 1 pc Jantzen 6.8mH wax coil.

• 1 pc Jantzen .20mH wax coil. (Optional: 1 pc .25mH Jantzen wax coil and 1 pc .27mH Jantzen was coil. You can use any value    from .27mH to .18mH to suite your taste. Also, rather then buying all those coils you can use a .27mH and gradually unwind it one meter at a time until you get it perfect for you. The higher the value of this coil, the more you will roll off the high end.)

• 1 pc Duelund 10R Cast resistor.

• 1 pc Duelund 8R2 Cast resistor. (You can vary this resistor to balance the full range driver output to the woofers output.  Increasing it will lower output, deceasing it will raise the output.)

Yeah, for sure he must have been taking notes from Jeff Day's outboard crossovers for his Tannoys.  I never tried pricing them out before, but he must have put 2 grand + into them.

I also found this on a quick search: http://www.modelpromo.nl/audio-dandy/reviews/Leon/Leon%20Huijgen%20Leonidas%20Va...

It was actually written by Leon (the creator) and goes into how he cam about his values, etc.

The project continues to evolve.  I love the rich sound of the Tang Bands, but they can be fatiguing in the upper mids on some music.

Two things in the works:  replacing the Tang Band with the Eminence Alpha 8A and crossing the AMT at a much lower frequency.

I talked to Parts Express and they suggested that I cross both the Tang Band and/or Eminence at around 1500Hz.  That seemed pretty low, but I tried crossing the Tang Band at 1600 this weekend and it seemed to take care of some issues I was having in the 3-4K region and produced smoother sound overall.  I have read the AMT can go all the way down to 1200hz without breakup.

I have a couple songs that can split your head open and the new cross-over point passed the test.  Crossing at this point requires just a cap and a coil so I am not introducing a complex cross-over into the system.

I have yet to receive the 8As but should get them later in the week.

I have made some changes to Rachael as well.  More on this topic later but the amp already had flat stacked Jupiter caps and  Cardas copper binding posts when I got it.  I recently added Silver plated, copper RCA jacks, a Furutech Rhodium IEC and bypass caps on the electrolytic capacitors  (Thanks Will).  I upgraded the fuse a while back to a hifi tuning fuse (silver, I think).

I believe each of these adds offered improvements in detail.

I also found a pair of Westinghouse 807 tubes on eBay and they are much more "dimensional" than my other pairs.  Better 3D imaging and more engaging.

While it may seem that all I do is tweak, I have been able to do a lot of listening over the last several months.  Really enjoying my system.

For my cottage system, I have been running Betsys with a thrift store 15" woofer and a plate amp.  I don't have much room at the cottage so I was looking to ditch the plate amp.  

I have always liked the bass sound of the Emminence 15as so I consulted Randy at Caintuck Audio http://www.caintuckaudio.com

Randy was kind  enough to share indicator values for various cross-over points.  Armed with this information, I burned through an Amazon gift card and picked up some 15as and a couple inductors for crossing at 125Hz.

The bolt pattern n the Alphas was exactly the same as the thrift store 15s so no fiddling there.  Changeover and adding the inductors took less than 20 minutes.

Overall, a significant upgrade in the bass department and I didn't feel the need for a plate amp at all.  15as produce a very nice musical bass, but I was also impressed with how punchy they were.

Randy offers speakers with some 10" and 12" alphas which he feels are faster.  From what I remember, from Decfest they sound quite nice.

Yes, the Augies in my main baffles offer more grunt, but you have to power them with SS amplification.  These 15as produce a very nice bass experience for about a third of the cost and no additional plate amp expense either.

I'd love to make a quad Alpha pair Donnie.

Just no footprint for that.  Already catching hell for as large as they are with just a single alpha per side

What about building a rack/stand such as the one used by Pure Audio Project's Quintet series?  You could fit 4 subwoofers on that stand it would only take the space of one set of sub drivers.

Dave, I can zoom in and take it to 1/48th so you can see detail.  Maybe later tonight.

I have a fair amount of flexibility with the crowns on the Augies and the plate amp on the sub.   I just had to smooth out that 1-4K region and the Emminence 8a has done that.

I think the diffusers on all 4 walls really help smooth out the high end.

I'll post a comparison of this and my Betsy OBs as well.

And here are the higher frequencies at 1/48 octave smoothing.

And 50-100:

shhhhh.  Keep the illusion alive.

must.  keep. thread.  alive.

Summer has been busy but I have managed to work on my system.   I have gone back to the Tang Bands crossed at 1600 and stayed there all summer.  They just have more detail and a richer sound.   I continue to look for other substitutes.  I can't recall the name, but there is a guy up in Green Bay that makes an 8" driver that might work.  A bit pricey though.

My next move will probably be to upgrade the capacitor.  Its 25uf so I went the cheap route with a Dayton audio cap.  I have found some other options, but they are a little pricy for that big a cap.

The only other thing I did was add padding to the tweeter baffle to eliminate some buzz I would get on certain songs with just the right base notes.  Drove me crazy.  I really do need to build some new baffles but will wait till my mid-range quest is officially over.

I may have mentioned this in another thread but I have fiddled with Rachael and installed a new furutech IEC and done some bypass caps under the tutelage of Will.  Finally, I have gone to 6N5Ps for input tubes which I find really nice.  My overall sound just keeps getting better.

So much so that I have put plans for a 25th on the back burner for now.  Owning a Zen is still on the bucket list, but given I have a very pleasant listening experience right now, it feels a bit selfish to spend the kids inheritance on one.  I'd also like to hear one before buying it and that will likely be at the next fest because I can't get down there on a week day.

Having spent some time at the cottage this summer, I really have a new appreciation for my room/room treatments at home. I get good imaging at the cottage and appreciate the size of the room, but its just not as immersive. I am going to enjoy my dedicated room while I can because I don't see myself having one when we downsize.

Another thing I have gained more appreciation for is the Eminence 15As I now have in the cottage OBs.  I just love the tone.  At the end of the season, I plan to bring them back and put into my baffles with the Tang Bands/AMTs to see how that sounds.

Randy has me interested in working with the smaller Eminence drivers, maybe doubling up on them in a baffle that is not as wide as I have at the cottage.  A smaller footprint will make everyone happy but I am mostly interested in the speed.

So that's it.  Palomino over and out.  Enjoy your summer.

I may have mentioned I bought two more pair to have in reserve.  Excellent tubes for the price.  More detail and air than much more expensive Mullards and 6n23Ps.  I think more musical overall as well.

Do they have more of a recessed sound stage on your system?  They do on mine.  I have seen that with power tubes before but not input tubes.

It's not a bad thing per se, just different.

I am hoping we can do the DAC-off before the Fest.  August is busy so let's look to a September session.