What does one purchase after owning horns?

The low damping factor in effect changes the woofer's electrical damping in a way that increases bass output relative to what you'd get with a solid state amp. If the speaker designer anticipated this, he has tuned the box so that instead of the lower damping factor giving you a bass hump, it gives you more extended low bass.

I hear that:)

BTW Duke - the High Z output (12 ohm) won out.

I believe that minimizing the spectral discrepancy between the direct and reverberant sound reduces listening fatigue, and can explain why if anyone is interested.

Please do explain.

Duke,

Could you point us to examples of manufacturers or models that are well suited to a low damping factor amp (as a proud Atma-sphere S-30 owner I am quite interseted in your suggestions).

Duke, I realize you are not saying that horns "beam" when you mention "radiation pattern control", but that and other comments here seem to imply that a very limited sweet spot is produced by horn systems.

Admitting my own experience with horn systems is limited, I question this condition. I own a pair of rear loaded horns (C&C BEN) which may not qualify but a good friend first had AG Unos and now AG Duos. I believe his room is 20' wide with the Duos spaced by 10-11' with moderate toe-in. I can sit directly in front of one speaker and still hear a defined stereo image spread. This is not to suggest there is not a more precise soundstage presentation when seated in the middle sweet spot but in his room/set up I find his horns to present at least as wide of a good listening area as any box system I've heard in that room. Perhaps this is aided by the 4-5' separation from the side walls (a point which seems contrary to some other comments on horn systems).

If you would comment further it would be appreciated.

Low damping factor gives you a muddy ill-defined bass not more Bass...

amazing !!!!

Clio09, the listening fatigue thing goes back to how the ear/brain system processes sound.

When a sound first reaches the ears, a copy of it is stored in a short-term memory. Then for the next twenty milliseconds or so, all other incoming sounds are compared with the sound(s) in our short-term memory, to see if they are NEW sounds or REFLECTIONS, that is, repetitions of the original signal. If they are reflections, then they're largely ignored as far as directional cues go. This is called the "precedence effect" or "Haas effect", after the researcher who first reliably described it. During this interval, reflections still contribute to loudness and perceived timbre.

Now the way the ear/brain system determines whether an incoming sound is a new sound or a reflection is by "looking" at its spectrum. If the spectrum is the same (or close to) that of a sound that's in the short-term memory, then it's a reflection. If it's obvoiusly different, then it's a new sound.

So, what about a reflection that's quite a bit different from the original? Well that hasn't been thoroughly investigated yet, but I believe we would find a continuum along which a spectrally-different reflection goes from "easy for the ear/brain system to correctly classify as a reflection" to "too distorted to be reliably classified". And I think that as the spectrum of the reflection differs more and more from that of the first-arrival sound, the more processing the ear/brain system has to do to correctly classify the reflection. In computer terms, it's like a task that uses up a lot of CPU power... and so the CPU heats up (we get a head-ache, after about 15 or 20 minutes): Listening fatigue. This isn't its only cause, but I believe it is a fairly common one.

Now remember that during the time the ear/brain system is ignoring directional cues from reflections, they are still contributing to loudness and perceived timbre. So a speaker may measure "flat" on-axis, but not sound "flat" because of the timbre-skewing contribution of the reverberant energy.

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Roscoeiii, I don't know the inner workings (including the impedance curve) of enough other manufacturers' speakers to give a really good answer to your question. Coincident comes to mind, and I think that KCS and PiSpeakers and Omega Loudspeakers and Tonian Labs are likewise strong candidates. Yours truly uses a variable-length port system so the box tuning can be adjusted for different amplifier damping factors (and different low-frequency acoustic environments).