GoodSoundClub - Romy the Cat's Audio Site

In the Forum: Horn-Loaded Speakers
In the Thread: Other Ways of getting Special Tone from a loudspeaker.

Post Subject: Dual-Quasi-Helmholz "Tapped", Doped Horn?Posted by Paul S on: 12/4/2009

Moreart
Double-driver "back horns"? I am not sure what you are asking about, or what exactly you are promoting, but I do not agree with lightweight, square-section horns, because I have never heard one that worked, apart from shifting certain frequencies around unpredictably. I did some of my own earliest experimenting with the old "theater" horn speakers, like the VOT, with their "folded" plywood "LF" "horns", some with "corner placement", and I would not go back down that road again. Forget for now that I replicated a couple of those "horn" profiles in cement, and they still didn't work...

Tapped horns? For that matter, I never heard a Danley-type "tapped" horn, either; however I am somehow more "convinced" by this "argument", at least as far north as upper bass, possibly lower mids. If the latter, that would be very cool, indeed; almost a freebie. IF it worked this  MIGHT (finally) power up that always-too-anemic range. But I refuse to get my hopes up.

"Resonators"? There have been a couple of occasions - the right drugs and the right music - when I heard Helmholz-type speakers sounding very "good". But in my experience this sort of "good" is usually a tip-off that the attractive quality will soon become annoying.

Double (spherical) horns? As Romy keeps trying to tell everyone, horns do not solve problems, they create problems. Cough up $4k to have that Bad Boy turned for you by someone who knows how, mount your $2.5k drivers, listen, and weep. Since I have no serious idea how to build a good single-driver horn, why would I try doubling drivers? I think I understand the "theory"; but the minute you pressurize a driver, all bets are off, and not just with regard to tone, but regarding everything. Basically, pressure changes everything. I'm not saying it could not work; but I am saying you'd better have either low expectations or very deep pockets (and infinite patience) if you start down this path.

Double wood-ish labyrinth?  For tone? I certainly don't know what to think. I realize as ponder it that my own idea of "blending" drivers for overall tone does not necessarily mean completely homoginizing them. And there are other things (besides tone) to consider, of course.

Of the multi-driver ideas, I am already down the road a ways with OB, which basically does NOT do bass. But there are some "advantages" with respect to tone and imaging, and I am curious to see how far I can push it. Having no experience with the Danley-type, I am looking at it as a possible way to get some extra power where I need it, possibly at the expense of the "correct" tonal variety. I am not sure what, if any, advantages would be gotten fom two drivers pumping simultaneously into a semi-stiff, lightweight labyrinth.

Again with the dope?  For some reason we keep re-visiting the diaphragm doping. Beware! It sounds like some folks do not get the concept of the "dope".  How many drivers will they burn through to find out that "change" is not always for the better. I recommend messing with stick-on dots or dabs of "museum putty" first. And understand that someone might refer to Budification as "doping"... Dope your de-whizzered Lowther if it will make it roll off 3 dB/octave from 1.85k. Otherwise, don't do it.

Paul S

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