when mixing a orchestra with many diffent microfones (near for every instrument and far) I normaly use two or maxium three reverbs for the hole production.
But using the IR-Reverb correctly, you have to use a different impulse response for every instrument - depending of the position in the room where the musican played the instrument. I know that the vsl-guys are working with that fact on the "mir-project".
Has anyone an idea of the sound-diffence using one or several impuls-responses? Any demos?
My approach is that you should not aim at "physical" correctness but at "psychophysical" effectiveness.
That means, that by whatever means, try to realize a convincing placement of instruments (thus: by using your ears, not physics).
For this purpose I use for instance Waves TrueVerb ER's (not the tails!) on dry instruments for put them "backwards" to mix them with more wet instruments. Then I apply IR reverbs for the front and backward instruments with an accent on the reverb tails.
My personal opinion is that you will not get optimal results by just applying "correct" IRs. You need to "fix it in the mix" with EQ and ERs, etc.