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I was wondering what is the reason behind positioning a third mic a few feet away from a basic stereo AB. I noticed this on the three tenors in Rome for example. Here is a link to understand better my curiosity.
Hi This will only cause phase problems if it's routed to the same output as the stereo-pair.
Except this won't be a stereo pair. Recording vocals in stereo is pointless, small movements between mics are translated as large movements between speakers. (MS is or Binaural works though)
Usually one mic is either a) fail-safe b) different gain or both.
The third mic could be for 1) to counter very high SPL on crescendo or fff parts. 2) to capture a separate feed for transmission somewhere else.
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