"I plan to give it away for free to everyone following this thread"

pant, pant...drool, drool.......my saw is warmed up and ready to go!

ok, i am ready to buy the plans... i may overdraw my account,  but i feel these are worth it! Anyone in the market for a pair of a/d/s L1590's? i need to finance a pair of Decware Crown Imperials!

Had an interesting revelation this evening while sitting in the shop listening to the Imperials. A new audio term that I will call "transient balance".  While I was listening tonight and pondering the contrasts between what I was hearing from the Imperials and what I would be hearing from a conventional pair of audiophile speakers, I realized something.  

One of the many reasons why conventional audiophile speakers could never sound like this is because the transient balance of regular speakers changes from driver to driver - from woofer to tweeter.  It also changes between the bass and midrange frequencies of a single conventional woofer.  This is what lets your mind know that you are listening to speakers rather than the real thing.  I mean let's face it, if your stereo actually sounded real your mind would short circuit and you would be struck with fear - not unlike seeing a real ghost.  

Anyway, these speakers seem to have a transient signature that is in tact across the entire frequency band.   Besides the Acoustats, I have never heard a speaker that did.  And even though the Acoustats are technically superior on paper, the horns have velocity in the bass and dynamics that even the acoustats could only dream about.  

Transient balance is a definition of transient response across the frequency balance of a loudspeaker.  Regular speakers have wavering transient balance that usually declines with frequency.

All of this is frankly a surprise to both Paul and myself.  Even though this is the 6th time we've built Imperials, they were all by the original plans and with a single driver.  And they were good, but warmer and slower.

Remember, or FYI, back in the 1980's Paul made me build a pair of these so his wife wouldn't see him making them.  I guess he thought he could hide them in his garage.  I agreed and after finishing the first cabinet I robbed a 10 inch woofer from a pioneer bookshelf speaker and stuck it in the cabinet to see what would happen.  The bass response I heard come out of that single 10 inch woofer was so mind blowing that I made a decision right there and then to devote all my attention to audio, the reason DECWARE actually came to be.  I heard two identical speakers, one in the bookshelf cabinet and one in the Imperial and could barely grasp the difference.  It taught me in no uncertain terms that there WAS magic in audio and I wanted more of it!

Cheers

Steve

>I have never been a person to listen to music loud because my distortion alarm always goes off about half way there.  On these speakers it has not gone off yet, and I'm sure we have listened in excess of 120 dB from time to time.  My ears have yet to ring from listening to these, yet at lower volumes our own band has created the dreaded ringing you hear when you go to bed later that night.  That means ringing is not tied to SPL, but rather a side effect of distortions.<

If you recall, a while back I mentioned having read an article about evidence suggesting that one could listen at much higher levels to sound that sounded good without damaging ones ears. It had to do with the ears being relaxed because you are enjoying what you are listening to. Any distortion would cause discomfort, and cause the eardrum and such to tighten up, and you have listener fatigue soon followed by ringing, and eventually, damage.
I don't think anyone took it serious at the time.


On another topic:
>I heard two identical speakers, one in the bookshelf cabinet and one in the Imperial and could barely grasp the difference.<

I have had similar experiences. The 10 inch drivers I have now sound far more alive in the TQWP cabnets then the one fourth the size bass reflex boxes they came out of. The origional boxes are well built and seem to be tuned correct for the speakers. The bass from the TQWP's is just much more alive sounding. Makes me wonder why anyone would want a small bass reflex speaker anymore.
Dave  

Steve,

What you call "transient balance", I call "linear dynamic tracking", I think we are speaking to the same thing.  Meaning that the entire speaker can product the same level of dyanamics at all frequencies equally particularly how this relates to the speed of each driver.

My ideas of how to go about achieving this are a little different, so I am very interested in what you come up with in the end.  I am thinking of having a compression driver that extends as low as possible, below 500Hz, and a front horn loaded 15" woofer below that.

I like your idea of mismatched drivers, having that ability by two 15" drivers in each speaker is a real plus.  Often I feel it is not the tecnology that is flawed often, but how it is implimented.

I think with your offer we will have more people following this thread now.  I can't wait to see what the total size of these speakers is, so that I can see if I have enough room for them to try out.

TG

My Dad is no longer using his barn. Perhaps I should build these and turn the barn into a suitable listening room. The haymow, with arched roof, is part of a smallish barn, but still way bigger then a typical living room. What a place for parties!
Dave

Terry,

Folded or not, TQWP enclosures are floor standing.  The interaction with the floor is an important part of TQWP bass performance.  A pair of floor standing speakers in my MULTI-purpose living room is out, as there simply is no room.

I have 2 pairs of small bookshelf speakers that get exchanged.  The 1st pair are 1st generation ProAc Tablettes that Mr. Deckert did a MAJOR overhaul on a while back.  The bass performance of the Tablettes is remarkable considering that the cabinet volume is about 1/3 ft.³.  I power the ProAcs with either my H/K Citation II or my AVA FET-Valve.  The efficiency of the Tablettes is TOO low for them to be a good match for a ZEN amp.  The 2nd pair of speakers are my own design that use 94 dB. efficient (nominal) drivers in a 0.55 ft.³ enclosure. The main driver runs full range.  A 2.2 muF. capacitor keeps low frequency information out of the tweeter.  FWIW, the simulation plot for the main driver and 56 Hz. vented enclosure combination is flat within 1 dB. down to 50 Hz.  I use the "homebrew" speakers with my SE84Bs.

STEVE,

Do the Imperials sound best when close to the wall  ?
I think most would not want them out from the wall
as they are pretty hefty.

What do You think the overall Speaker Impedance
will be when all said and done ?

4 ohms would probably make the most sense, as
this would work well with ALL the Zen amps.
Of course with the very high sensitivity this probably
isn't a large concern.

Homey