Harrylavo made some excellent recommendations, if I may paraphrase:
- We want to minimize the early sidewall reflections, ideally with distance.
- We want to minimize the early reflections off the wall behind the speakers, again ideally with distance.
- We want to re-direct the early reflections off the wall behind the speakers so that they don’t bounce directly towards the listening area.
If I understand correctly, the idea is to manage early reflections in a way that reduces what might be called "small room signature". By that term, I mean the aural impression of being in a small acoustic space, rather than in the acoustic space (or "soundstage") on the recording. (Notice Harry is not advocating absorbing these potentially detrimental early reflections - I’ll come back to why his is such a good idea in a minute.)
There is in effect a competition between the acoustic signature of your listening room and the soundstage on the recording. The acoustic signature of the room is primarily conveyed by the first reflections, and the acoustic signature of the (typically much larger) recording venue is primarily conveyed by later-arriving reflections. Notice this key aspect of harrylavo’s recommendations: He is NOT using absorption, so he is PRESERVING the beneficial late-arrival reflections! (In particular, he is preserving the SPECTRAL BALANCE of these late-arrival reflections).
How is the ear/brain system able to pick out these soundstage-signature reflections on the recording from the later-arrival reflections that come from all around the room? By matching the spectral balance of these reflections with the spectral balance of the first-arrival sounds. Thus it is important that these reflections be spectrally correct, or nearly so. To the extent that absorption alters the spectral balance of reflections by selectively absorbing shorter wavelengths, it is weakening the soundstage signature we’d like to enjoy.
I’m not saying that absorption is always a bad idea, and often it makes a worthwhile net improvement, but if we can find a benign acoustic solution to detrimental early reflections - like harrylavo’s recommendations - ime that facilitates hearing the soundstage on the recording. Not to mention the richer timbre we get from a well-energized reverberant field.
So imo the more we can do to minimize small room signature without degrading beneficial late-arrival reflections along the way, the closer we can hope to approach that elusive "you are there" kind of presentation.
Duke