Ahh, but how to allow the first side-wall reflections and also absorb the opposite wall reflections? Can it be done?
don't know how someone expects to have a good image if when what is supoused to come from the right is copied on the left and vice versa. the nearer wall reflction might be constructive, but the oposite wall reflection is terribly desctructive
The mystery is called "precedence effect" - once the idea were the sound comes from is established in the beautyfull mind of the listener ( I hate to talk about some anonymous "the brain", it's so inhuman ), that idea is kept for longer. Reflective sound is subsummized under that first direct sound. If it is somehow plausible in terms of spectral content and other cues.
Ehm, to elaborate on that a bit more:
In real life, which actually exists, and there is live music in some room, which is possible even with real musicians--one has the opportunity to turn the head a litte, to move a step aside and so forth, that would only confirm (!) the idea of the direction where the sound comes from
In stereo the contrary is true--move or turn head, the virtual "image" is disturbed, maybe destroyed
The latter is not related to the reflections. The stereo illusion is, even with speakers, head related, not room related. It is always about a combination of relative amplitude and time delay at the head of the listener (me for instance) which gives a first and sofar final impression of the localization. And that is kept for some time. The room dependend reflections are within a wide margin of no further effect.
Stereo is fragile, because that first impression cannot be confirmed by biological reflexes, namely moving the head. To the contrary. To train stereo seems to rigidly withstand natural reflexes, maybe?
That simple.