[avaserfi]

Ethan Winer wrote:

Exactly, and I can't imagine how anyone could consider such a terribly skewed response to be a desirable artifact. Worse, the comb filtering response changes dramatically over tiny distances, like an inch or less. This is why untreated early reflections are so damaging to imaging. You move your head just a little and everything changes. Versus how imaging should be where everything is locked into place, and comes from the same location no matter where you are in the room.

Perhaps I have not made myself completely clear. It is well known that proper distances between each loudspeaker as well as the listener is needed for proper speaker placement in any room. Although, it doesn't seem that a room the size you have previously mentioned would be required. I am speaking of a system with proper placement and full treatments under the methodology that first reflections should be encouraged with proper off-axis response.

I fully understand the idea of comb filtering and the artifacts that occur from doing so, but the relevant credible research shows that in spite of this artifacts the slightly delayed reflections are desirable for stereophonic listening.

Also, I am very well aware of the factors effecting imaging: Loudspeaker room interaction, symmetry of response with respect phase with response to listener position and lastly treble response. All these variables can be controlled with proper treatment and equalization even with first reflections left "live."

This brings up another question with an omnipolar speaker would you treat the first rear to the speaker reflection? This is another situation that would cause even more comb filtering and has been proven through credible research to increase stereophonic listening pleasure.

Ethan Winer wrote:

I've read Floyd's position and I respectfully disagree. I don't know of one other expert who agrees that early reflections in a typical domestic size room are desirable. And by expert I include every professional designer of recording studios I know of.

I have talked to multiple professionals [same meaning as yours] who have differing opinions on the subject. For strictly two channel listening in a completely dedicated room with proper treatments I have gathered that many of them follow Toole's research. In fact, one specifically told me the gut reaction to treat first reflections is an outdated practice from treating recording studios.

It seems logical that application would change treatment needs after all.

Ethan Winer wrote:

Here ya go:

http://www.realtraps.com/rfz.htm

Figures 1 and 2 tell all. This is in addition to many listening tests.

Do me a favor? Please describe your own listening room and its acoustic treatment. If you can post a photo of the front of the room too all the better. Thanks.

--Ethan

I am aware of your website, but there is a difference between that and Toole's work. No offense is intended by this statement, but Toole's research methodology was peer reviewed before being published in the JAES while your studies were not. Furthermore, there is no discussion of the listening tests and the methodology of your research on the site you supplied as far as I am aware.

My current room is not dedicated and laid out in an asymmetric way in which treatment of the first reflections is necessary. I am referring to an ideal circumstance far from my own. I do however have a friend with an extremely high quality omnipolar 2-channel system with axial and off-axis response near identical to each other. He personally conducted blinded studies with both musicians as well as other individuals with his results mimicking Toole's. Personally, I have gone into a Hi-Fi shop and played with such treatments in a subjective manner to the same effect as well.