There is a rule-of-thumb (a formula in acoustical engineering terms) for how far one must be from the wall behind the listening position when using diffusion rather than absorption. I didn’t bother to memorize it, as it told me I couldn’t use diffusion on that wall, my currently situation requiring me to sit too close to be able to do so. I'll bet a Google search will lead one to the answer.
Question: Sound Treatment behind the Listener?
I have treated the 1st and 2nd reflection points and I have sound panels between my speakers. I also have tube traps in all 4 corners, but I am not sure what (if any) should be done with the wall behind the listener.
That wall presently has a DIY rack system that holds about 5000-6000 cd’s. I believe it helps scatter the sound. But I’m not sure if that is the right approach.
So, what are you guys using on that wall? Diffusion, Absorbtion, Reflection? Anything else?
I would appreciate your thoughts.
ozzy