possible problems with phase cancellation

[wanderer]

Hello. I´d like some information about possible problems with phase cancellation.
Recording piano with 4 mics (2 spaced pairs)... 2 omnis / 2 cardioid ... if you mix them, do you meet significant problems of phase? Can you advise me how to avoid them?
If recording chamber ensembles with spot mics in addition the main couple ... are there basic rules to avoid phase cancellation problems?
I´d appreciate advice, books, etc..

[Jim vanBergen]

here's a start. There is an excellent chapter on this in Glen Ballou's Audio Cyclopedia.


THE THREE TO ONE RULE & PHASE CANCELLATION FULLY EXPLAINED

Phasing

Hope this helps.

JvB

[studer58]

Originally Posted by Jim vanBergen

here's a start. There is an excellent chapter on this in Glen Ballou's Audio Cyclopedia.


THE THREE TO ONE RULE & PHASE CANCELLATION FULLY EXPLAINED

Phasing

Hope this helps.

JvB

It's almost certain that with orchestral recordings, where you have a wide 'source' of sound, the use of multiple microphones to cover the stage width and depth, you are going to get such comb filtering cancellations ? Perhaps less so with spot mics vs the main pair, since the mic to instrument distance ratios are quite radically different...but almost certainly with the main pair vs outrigger mics along the front of a stage, especially if they are spaced more or less equidistant from the players (as in a typical 1/3, 1/2, 2/3 across the stage front placement). Is this so ?
Ray