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Remember that no dipole speaker is capable of ZERO interaction with the side walls of a listening room. And remember that double-blind testing of room treatment changes with near-instant A-B comparison switching time is very difficult, if not near impossible.
Hi Wayne,

To be clear, none of my comments were directed at your work, but referencing what Primare had posted.
Yes, there are zero blind test studies that support lateral absorption improving things...and a of a lot supporting the opposite. This is what I am referring to. Tooles book and articles repeatedly reference the AES papers regarding phantom central imaging and ears only listening preferences for lateral reflections in home listening environments. I could reference all those AES papers, but it requires membership to read.
Actually, it was Tooles book referencing this that created much uproar in the studiophile community and numerous personal attacks against him not understanding reflections, from the same folks who gave us LEDE. Of course, they couldn't cite any blind studies to support their intuition beliefs about reflections either. There aren't any.
That uproar lead directly to this paper: http://www.aes.org/e-lib/browse.cfm?elib=16640
Studiophiles claimed that all the papers Toole referenced didn't apply to them, because they had much greater sensitivity to (and awareness of) reflections than all the trained listeners used in the AES papers.
So McGill University took that exact matter to task and did a listening study using only seasoned studiophiles (the types that hold such beliefs).
The results were rather amusing.:)
All that said, I have zero issue if someone wants to treat every inch of their space...if it pleases them. Ultimately, that's all that matters. I only take issue with statements about this being "better"...to anyone other than them and their personal taste.
The science clearly runs contrary to this.

cheers
 

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We??
I use dipolar speakers also and would never "treat" the sidewalls. There is large body of scientific evidence to support this. There is zero scientific evidence to the contrary.
Here is a nice summary of why: http://www.audioholics.com/room-acoustics/room-reflections-human-adaptation
Floyd's book contains all the AES references to the studies that support this. This is not "his opinion". To the contrary, it is based on the established science. Much of what is bandied about on audio forums is studiophile folklore, based on sighted beliefs and "intuition" long ago discredited (like LEDE). Again, there is zero science to support such beliefs.
With 2 channel phantom center image audio, side reflections play a critical role in filling in the acoustic interference combing from the L and R speakers, increasing intelligibility and clarity of the central images. This has been double blind listening tested repeatedly. It is not "opinion".
If you wish to please your eyes or an "ETC" measurement pressure mic, treat away. If you wish to please your ears, read Floyd Tooles writings and videos, which are a nice compilation of a large body of work by many many scientists in the field of acoustics study.
Btw, a little known fact is that the highest ever rated speakers (blind, controlled, "trust your ears only" listening) during Tooles time at the NRC, was the Mirage M1, a bi-directional radiator speaker, much like yours. Properly implemented in a room, they can lead to very enjoyable sound, specifically related to spatial rendering of stereophonic/phantom center images recordings.

cheers
Thanks for this, I'll have a read and see if I can come to understand it. Sorry for the later reply. Tappatalk wasn't keeping track of things.

Related to your other post. The 30 degree is coming from Martin Logan. 30 degree curvature in the panel resulting in a 30 degree dispersion pattern/angle.

On a similar note. How about treatment of the front wall? I wonder if I should go for an acoustic transparent screen to allow for acoustic treatment of the area behind the screen.
 

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No worries. With dipoles, if you are going to treat the wall behind them, aka front wall, I would strongly suggest diffusion, not absorption, unless truly broadband, bare minimum 6" thick (3' better, yes feet).
The dipole panel radiates 6db less power into the room than the monopole bass section. Turning down the treble further with absorption not such a good idea for power spectrum at listening seat. Of course, preferences count, so YMMV
 

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Thanks for putting together this information. It looks like the recommendations are largely empirically based, but can anyone explain why these positions tend to work best? I've seen various places recommending placement based upon the golden ratio, but I haven't seen any explanation of why beyond vague statements like it 'reduces room modes'.

In addition to being an interesting question, I'm curious because another forum recommended I deal with my odd shaped room by placing the speakers centered the room's diagonal instead of centered between two parallel walls. This has been much better, but the placement was largely arbitrary - I looked for a spot that got the speakers away from wall while leaving enough room for my listening position.

Unfortunately, you cannot directly mimic the ratios provided here for this arrangement. For example, if I keep the distance between the speakers the same as the distance between the midpoint of the speakers and the wall, then the line between the speakers will have dimensions 1:2:1 (moving along the line between the speakers, distance from wall to first speaker is 1, distance between speakers is 2, and distance from second speaker to wall is 1).

Any thoughts on what I should be looking to do in my case? Thanks!

And for what it's worth, I have REW measurements from the current position as well as a lay-out of my room available. I'd love some feedback and thoughts on how to start putting together room treatments, but should this wait until I find a better spot for placement, and in either case, is this something I should place in another thread (if so, recommendations on which thread?).

Thanks again!
 
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