The gent I share an office with at work is putting the finishing touches on the last project on his plate before he starts on my SO Imperials .....

A couple of nights ago, we hauled the 10 sheets of good quality 3/4" oak plywood that will be needed for the project into his woodshop.

The Imperials should fit very nicely in my listening room, exactly filling up the spaces between the edges of the center curtain and the side walls.





Of course, I will have to do away with my chic $12.00 designer floor lamps .....

I expect that the Imperials will work extremely well with the Parker Audio Behemoths or The Horns (as in the photo).

Based on what I heard at the most recent DecFest, this will be the end of my audio journey ..... and I want to offer in advance my heartfelt gratitude to Steve Deckert and Bob (Zygi) for their help and inspiration in making these wonderful speakers available to the readers of this forum .....

Additional photos and comments to follow, as available .....

Randy

Howdy gexter,

The "official plans" are not available yet.

The plans that I have are from this thread :

https://www.decware.com/cgi-bin/yabb/YaBB.cgi?board=Imperial;action=display;num=...

My friend says that he can build them from these plans, and a phone call or two to Steve or Bob .....

Take care,

Randy

I'm looking, but I can't seem to find the "green with envy" smilie . Alas, the most important ingredient, ie: the room is missing in my set-up. We'll be anxiously awaiting pics etc, Randy!

[quote author=DirtDawg  link=1139429263/0#3 date=1139434851]


"A couple of nights ago, we hauled the 10 sheets of good quality 3/4" oak plywood that will be needed for the project into his woodshop."

Here I'm worried that you should have gotten 2 extras ..... just in case your buddy gets a little off on a cut or you can think of any way to improve the rigidity of ..... if you think you need 10, you should get 11 or 12 to be sure ..... worst case is you build a super solid base for them ..... or a better bass trap to address some of the ..... uhmm ..... anyway .....

"The Imperials should fit very nicely in my listening room, exactly filling up the spaces between the edges of the center curtain and the side walls."

For some reason I thought you were going to lay them down ..... as instructed ..... the same way Steve had his in the pix ..... I guess I'm just not considering all the options available when you have all the bass you could ever ..... the mouths go down right? ..... so you will be able to make some nice bass traps for the ceiling junctions ..... but, wait .....  you're out of plywood .....





"Of course, I will have to do away with my chic $12.00 designer floor lamps .....  "

Negative! Bad idea! The only problem with the lighting scheme is that the poles are too long ..... you just need to have the center five feet of extension removed by the same, really handy, buddy from work. The lamps will create interesting, romantic shadows and intense, illustrative highlights that spill out mysteriously across your new ..... just don't throw them out, yet!

"I expect that the Imperials will work extremely well with the Parker Audio Behemoths or The Horns (as in the photo)."

..... or just about any other likely prospects you can think of in the future as you continue to explore .....

"Based on what I heard at the most recent DecFest, this will be the end of my audio journey ..... and I want to offer in advance my heartfelt gratitude to Steve Deckert and Bob (Zygi) for their help and inspiration in making these wonderful speakers available to the readers of this forum .....  "

Now, see ..... this P155E5 me right off! You can't just leave! You're making it sound like this is "iADIOS, AMIGOS!", but it can't be. This place can't be without it's demi/semi/hemi/god any more than I could go all week without ..... Randy, I just spotted this ship ..... I can't quite catch up, yet and I've even had trouble keeping it above the horizon line at times, but we ..... I ..... I still need your inspired and well traveled guidance along with your understanding humor, and uplifting and witty distractions at times to offset the natural course of entropy that all my endeavors seem to push my mind towards, lately .....

"Additional photos and comments to follow, as available .....

Randy"

Say you're not going away, Randy! I would like to see the "Randy's Imperials" thread become one of those that never quite dies .....


[/quote]


Howdy DD,

As to the number of sheets of plywood, you are probably right ..... if my buddy Mike slips with the saw, we're probably in trouble.  Fortunately, he's not a big drinker, so I'm hoping for a "steady hand" with the saw .....

Concerning my chic pole lamps ..... I was actually thinking of removing the poles and hanging the remainder from the ceiling.  Your thoughts about the "interesting, romantic shadows and intense, illustrative highlights that spill out mysteriously" are pretty much on the mark as to the effect I am currently getting ..... although since 99% of my listening is done "solo", the romantic part is pretty much wasted ..... ???

"You can't just leave! You're making it sound like this is "ADIOS, AMIGOS!""

Very interesting ..... my buddy Mike said the same thing when he read my post ..... but, I can assure you that the readers of this forum will not be getting rid of me quite that easily .....

The comment about my "audio journey" is simply referring to my quest for new equipment.  Truthfully, I haven't made any serious changes to my system in a long time and I am deliriously happy with the sound I am getting at present.  However, the SO Imperials are really something special and I sincerely believe that they will be the icing on the cake.  The fortunate few who heard the Imperial / Crusader combo at the 2005 DecFest know what I'm talking about ..... and after my "Imperial Experience", there is no turning back .....

I'm afraid the forum readers will be stuck with me for a while longer .....

Best wishes,

Randy

If you are open to experimenting with speaker placement AND listening position placement, and you sit down to listen to music you will find a spot that will amaze you.

But I would start listening with only one, then add the other later.

I was dead serious about the plaster though.  If you do have plaster you might as well start ripping it out now and put in drywall with extra screws, as it is very annoying hearing it vibrating on the wall frame boards.

Howdy boydon_lepasci,

At the 2005 DecFest, we had a pair of 95 db efficient 2 ohm Parker Audio Crusaders wired to a single Zen Select in parallel with the SO Imperials in Steve's garage / listening room.  I'm not sure what the actual dimensions of the room were, but the musical presentation was absolutely mindboggling.  It wasn't because of the SPLs (which were more than adequate) ..... but more the size of the soundstage and the feeling of the "recorded space" that was evident in a way I have NEVER before experienced.  The front wall, side walls and ceiling of the room were simply removed from the equation.

I don't know any other way to explain it ..... but the whole room felt like it was "breathing" ..... 8)

The bass instruments weren't trouser flapping and tooth rattling like you experience with a cheap subwoofer or cheesy home theater system ..... they were just present and realistic and effortless.  

Steve made the observation that the Imperials give the music "a place to go" ..... ???

I don't pretend to know exactly what is taking place, but I can understand what all the fuss is about among the fans of large horn loaded speakers ..... there is nothing quite like it.

Since I'm not much into head banger music, my reason for wanting the Imperials is to impart a sense of realism to acoustic blues and small ensemble jazz ..... and I have a feeling that I will get exactly what I'm looking for ..... and then some .....

Of course, it's also possible that I might discover just how good a few other musical genres can sound once these beauties are part of the system .....

Randy

[quote author=Caintuck Randy  link=1139429263/0#10 date=1139450987]

Steve made the observation that the Imperials give the music "a place to go" ..... ???



Randy [/quote]


I have thought about this for awhile now. Perhaps the massive wavefronts are basically "exciting" the air molecules and allowing them to conduct the mids/highs better. That or they allow the first passing of the signal, but impede a reflection, much like a diffusor but the bass air "absorbs" the reflection because it is moving as well. Wonder what hooking the sub 180 deg. out of phase would do to the soundstage when you observed this "widening" effect?  

Take care,

Corey

EXCELLENT THREAD!

[quote author=bassboy  link=1139429263/0#5 date=1139436976]This arrangement is going to look magnificent.  But two imperials in a room that size is kind of like killing mice with dynamite.  
[/quote]


Have you actually tried killing mice with Dynamite?  Cause if you haven't I suggest you do at least once!



But in all seriousness, I am going to have to demand this thread be kept alive forever.

Have to agree with 60.

thats also an awful large amount of wood and time to end up it not working the way it should.
why risk it?

Thats the major reason I would build a std Imperial sub right now without the exact Imp SO plans

[quote author=60ndown  link=1139429263/15#15 date=1139498117]i would wait till steve releases the ACTUAL plans for the so imp. it would be a p.i.t.a. to cut a sexy enclosure to pieces because of a small overlooked placement of ply? anyone who is anyone knows the importance of patience? [/quote]

Howdy 60,

I talked to Steve and he said that the plan as it sits will work just fine.  I also have some photos that Zygi took as he was building Tim's (change_out's) pair of SO Imperials and according to Zygi and Tim they work VERY well .....

My builder has gone over the plans and photos with a fine tooth comb and is making ACAD drawings for the build.  He works in ACAD all day long and says that the plans and photos make perfect sense to him ..... but he will probably be calling Steve or Zygi to clarify a minor detail or two, as Zygi made a couple of small changes to the original when he built Tim's.

No worries ..... but I appreciate your concerns .....

Randy

As soon as I can verify the numbers it goes to draft mode and full scale drawings.

Change_out and Randy your my heros

1.6 watts for nice bass fill, looks like Steve is right on the money...again....

Are you using the Daytons or another driver? the dayton 295-130  ST385-8 15" series II woofer was mentioned
Fs 19
Qts .34
Is that what you went with?

Gex

Randy, bassboy and everybody else,

I'm with you all the way on horn designs. I think they're the only way to go if you can get your hands on quality low-power amps. I'm an efficiency freak so I like horns even with the SS amps in my budget. I even run to the "if more is better then too much is just right" side of things when it comes to SPL or HP. Not at the expense of SQ though.

bassboy, I caught your background in the other post after my question on this one. Have you read the Harman paper on sub placement? I think they only tried monopole subs for the entire test and your results seem to indicate a lack of corellation(sp?) for horns. Anybody up for another thread?

[quote author=bassboy  link=1139429263/15#23 date=1139544404]

I'll also be waiting for Randy's answer to the same question.  How long is that going to take, anyway?  Anyone else measured imperial output? [/quote]

As I mentioned to Tim in another thread, the friend who is building my Imperials is a "weekend warrior" when it comes to his woodworking ..... because he has a real job and a family to consider.  But, I have seen his work and he has a really nice wood shop.  He is also a detail freak and a perfectionist.

He's finishing up another project that should be done soon and estimates that the Imperials will be ready in four to five weeks ... I probably should have named this thread "The anticipation is killing me" ..... ???

Randy

[quote author=bassboy  link=1139429263/15#23 date=1139544404]Boydon - I have not seen any info on sub placement and any info you have would be a great topic for a new thread.  

Tim, please tell me what kind of frequency response you are getting, in particular, where low frequency starts to roll off.  I have guessed 40 is as low as it is likely to go with -3db at about 35.  I would love to be proven wrong, I would definitely buy new, lower fs subs.  As far as I know you may have the only pro-built SO's so I'm sure everyone would like to know.

I'll also be waiting for Randy's answer to the same question.  How long is that going to take, anyway?  Anyone else measured imperial output? [/quote]


At the fest, I did a sine wave sweep on the Imperial SO's so that those who attended could hear a true 20 cycle note.  There was no attenuation as the frequency dropped from 100 to 20Hz.

Also, a note about the plans linked to earlier in this thread.  The color picture posted is low res to prevent people from accurately building a pair.  I have a very high resolution grey scale image of the same thing that I have been e-mailing to those persons wanting to build a pair.  I remember sending one to Randy, but that doesn't mean he got it.  Make sure Randy that you have the right plans.

Recalling the incident with the mouse I started remembering all kinds of fun things that happened during my first couple years with Imperials out in that garage.  Paul and I tried every 15 inch driver we could get our hands on for about a year.  Then the crazy stuff began.  At one point we had two 15 inch drivers compounded and horizontally loaded inside the imperial by using the dead air space in the original 1956 design as a sealed box.  Then we reinstalled a 3rd 15 inch driver in the front.  This was the tightest bass we ever got out of them, I remember it was like being hit by a 2x4.  The best combination I ever came up with was taking a 1 cubic foot sealed cube, placing a 12 inch woofer in it.  Measured response in cube was -3dB at 120Hz.  It had no bass.  Then I screwed a 24 x 24 inch board to the back of the cube and installed the cube face first into the 15 inch opening of the Imperial.  The 24x24 inch board held the cube in place and sealed the opening where the 15 inch driver typically goes.  This turned it into the worlds biggest bandpass box and with the SPL meter set at 100dB at 100Hz it hit 124dB at 28.5Hz.  That btw, is one fricking serious bass note that you bones remember for a long time until the inflamation goes down.  Poor mouse...

One of my favorite things to do was stand out there in that garage and do the low frequency sweep - real slow.  I could make it sound and feel like a helicopter was landing on the roof.  Dave, who lived one block away (353 yards by straight line distance) has a beer stein collection that I could make rattle by doing these sweeps.  I figured out a radius from his house to the garage and estimate this effected about 20 houses nearby.

I liked and still do for some reason to call it "wazoo"ing the imperials.  I'm certain this addiction was irritating to people because once around 2:30 P.M.  I saw a guy running across the road about 2 houses down in his P.J.'s trying to find the little bastard who was making all this noise every day.  I guess he worked 3rd shift.

Awesome stories!

These are with the original, well your original imperial design?

I may have to build one for absolutely no reason now, I have no room for it, and no cash to pay for it, but I need it.

But honestly, for bass only, SO or normal Imperial?

As I will be taking the box apart again to add weight to the speaker cones or completely replacing the subs I now have a question about sand filling the dead spaces in the box.  I have read reports that sitting a sub in a sandbox (not likely for most people) and putting a 100 lb bag of sand on the top can improve response by up to 3 db.  The Dinsdale articles describe a method of using sand filled panels to actually make the box.  And sand filling dead cavities is generally accepted as good practice as long as you can deal with the extra weight.

I want to know if anyone has tried any of these options in an imperial and if it is worth it, as it would certainly be a lot of weight and my box is already well over 300 lb.

I have now read this thread at least three times and have to chime in. My acoustics instructor has all kinds of custom, very fancy folded horns with Lowther DX3's (pictured below). However, he has two Jensen Imperials in his "home office". I have heard his full 5.1 system with the lowthers and a klipsch folded horn corner subwoofer. He says his two imperials blow his horn-loaded 5.1 system out of the water. In his words "Nothing can compare to the Imperials."



I know putting these horns in an imperial thread is tantamount to blasphemy, but I decided to anyway.

It is my understanding he has the first of the two, with the rectangular footprint. He also gave the class copies of an original Jensen Speaker building manual (circa 1956) which has both designs detailed in it. So, I have plans for the original imperials (rectangular and corner design), but not Steve's new and improved design.

BTW, the illustrations in the manual are hilarious, very 50's!

[quote author=J_Rock  link=1139429263/30#30 date=1139590319]These are with the original, well your original imperial design? [/quote]
Hi J Rock, as I understand it these stories from Steve were with Jensen's design!  Steve did not come out with his improved Imperial until Christmas 2002 when he debuted it here in these forums in the "Hell Those Aren't Big" thread.  
He should be able to kill even more mice now.

Great news!  I 'm happy for you Randy.

Well ..... Saturday went well.  We worked for about 5 hours and got most of the big pieces cut and trimmed to exact specs.  Mike worked a few more hours on Sunday and got a good number of the smaller pieces cut .....

We dry clamped the outer pieces of the big box together so that I could do a little drooling ..... I created a lovely puddle .....

Mike promises to take photos at each stage of construction when he starts putting them together.

This might be the longest month of my life ..... ???

Randy

[quote author=Brian  link=1139429263/30#37 date=1140728993]The much smaller size makes that corner Imperial  interesting.  I would like to hear from someone who has used one of those.

Edit:
I found this in the classic Imperial thread:
"This is the "cut-corner" home version of the Imperial. Paul and I have built a pair of these also, still have them.  They do not compare to the full size imperial with one 15.  They really do not compare to the new models.  They do not go much lower than 37 Hz, and they sound sloppy compared to these new ones." - Steve D.

So I guess that answers that. [/quote]


I missed this entry..
I built a single of the corner Imperial in a SO configuration out of cardboard Some of it was wood and it was heavily reinforced.
they had to be in a corner and and worked well and now is a Imperial without the SO mod and seems louder but not as low but I never did any real testing.
I can't speak for the full range but my first rendition of this design was nice in the right location.
the horn mouth is much smaller and thats where the wall comes in..
I have them laying in the garage under my workbench with the top off and the horn extended by my workbench they sound great and low.

I would build the imperial over most designs in a sub and likely a full range if I had the room.
I have yet to build a full range Imperial design..

the Transflex design is in a attempted redesign at the moment and I am trying to convert it into a corner design about 8 feet tall. It was Johns idea to try it but I have not been happy with what I have come up with yet. I don't want to use all that wood on a bad design.

It ain't no horn but its a Jensen design to pick up where the Imp drops off.. I think its excessive low, but looks like fun..
So far its not looking good enough to follow through with.

How do you plan to drive the S.O´s Randy?

>>mod oop´s reread the thread and found you´re answere <<

Thank´s Randy

It will look ´funny to see the tiny zen driving those monsters  :) Very impressive  ;D