Quote:
|
Two waves that are out of phase will combine and cancel each other out resulting in a null wave.
|
In "laboratory" situations. In real life if you toss an SM57 on the cone of a guitar amp and a Ribbon mic dead center and blend them you'll end up with a nasally mess (unless you just hit the jackpot!)
If you are using a mixer with a phase reverse switch you put the phase of one of them backwards. Then adjust the second mic so that the sound is as out of phase as possible. Flip the phase switch back to normal again. Rinse repeat.
Back when I was a proponent of multiple close mics (I have not been for some time) I used this method often. It's often more difficult than I thought it should have been.
I could often cancel out everything but the top end air. Of course, the second I flipped the polarity back this meant I was losing the end air.
I consider my extreme fear of comb filtering to be a gigantic contributing factor to my improvement as an audio engineer.
Brandon