Has anyone here used multiple mic setups and placed them certain distances apart to create an intentional cancellation at a certain frequeny? I have tried this a few times with guitars and it sounded good. I have also tried this on other instruments with some sucess. Is this concept flawed? These figures are for easy figuring, but I'm thinking of using this concept in relation to drums by understanding the differences between phase with, as an example close mic to overhead mic. Close mic on snare @ 1.5" = 180* of phase at 4520hz with overhead @ 3 ft 4520 is in phase with the close mic at this frequency. Move the overhead 1.5" closer and it cancells. I am asking this just to be aware of, and possibly proactive with this. I realize that this can create variying degrees of cancellation across the spectrum. What do you think of this? Is it a waste of time to even consider this issue? I am going to work it out anyhow, just for the hell of it.