Many self-accompanied artists prefer to play while they sing. They may have a hard time achieving a satisfactory performance if they're required to overdub. And since the performance is the point of recording, there is benefit from trying to accommodate them.
Here's a technique that maximizes the separation between vocal and guitar (or other stringed instrument in the lap) while the artist sings and plays. The technique uses Figure 8 (or bidirectional) mics and places them to make best use of their pattern.
Some people react to this arrangement with concerns about phase coherence, but because of the high degree of separation, the secondary signal is too low to have an impact on the primary one.
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