Using multiple microphones for live performance recordings is quite common, especially if you want some flexibility working with the acoustics after the performance is done. I generally like to record with just one main stereo array, which completely depends on mic placement for balancing the performers and the room acoustic, but sometimes you just need to change things up a bit...
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For this recording, the main mic was an AKG C422 in M/S, with a figure 8 pattern for the side and a hypercardiod (just one click off of a figure 8) for the mid - that seemed to be best balance of some room acoustic, good definition of the instruments, and as little of the coughing and wheezing from the audience as I could manage. The AKG was about seven feet away from the performers.
The sound was a bit drier than I normally like, so I also put up a Jecklin disk with two Neumann KM183 mics for capturing more of the room. I was mainly interested in capturing the room acoustic, not the performers per se, so I kept the array high (as far from the coughs as possible) and relatively close to the performers (about 14 feet up and 18 feet back).
Here's the AKG. It could stand on its own, though, as I said, it feels just a bit dry and thin to my ears - a tad too close a sound, but nicely isolated from the audience noise:
This is the more distant Neumann Jecklin array. This room array is just there to give more space and body to the overall mix. This clip is at the the level I mixed with. Note the completely different character of the instruments and applause:
The final mix. No processing at all. There's no need to time-align, since the delay from the extra distance of the Neumann array is about ideal for reverb. The Neumanns have a lovely low end which complements the AKG's detail and brightness. Mixing the two arrays together gives a nice smoothness and bloom to the sound, while keeping lots of detail:
By the way, applause, which is essentially pink noise, is often a good indicator of tonal character when mixing multiple mics in an acoustic space.