Close-micing (which is the term of art for what you're describing) would potentially be interesting in terms of letting people remix the recording, but it would

Close-micing (which is the term of art for what you're describing) would potentially be interesting in terms of letting people remix the recording, but it wouldn't "let you recreate the experience of sitting anywhere in the concert hall." Recordings made from close-miced instruments sound very "dry". That is, there's little to no 'room tone' to give you a sense of space or place. I've listened to recordings like that, and it sounds like you're having the instrument wired directly into your brain. In some cases that might be what you want -- a lot of pop music (virtually all) is recorded that way. I prefer my classical music recorded "wet", on an X/Y or ORTF pair setup. This is basically where you take two identical microphones and set them up down in the seating area of the concert hall, right in the acoustic sweet spot of the room. Done well, and played back on a good set of speakers, you can hear the placement of various instruments across the stage. (Another fun technique is binaural recording, which is designed for playback on headphones. It is not very popular right now, though.) There are some techniques to make a "dry" recording "wet," by basically faking the room tone, but they're, well, fake. Tossing in a little reverb and messing with the EQ is never going to give you the same effect as the natural acoustics of a concert space. A lot of modern recordings have a mix; they'll use some mics up on the stage (relatively dry), some down in the audience area, and others on key instruments to give the engineer flexibility later on. But a lot of really excellent classic recordings from the 50s and 60s were done with nothing but two condenser mics. What you could probably do, if you really wanted, would be to do some sort of multichannel recording using a big microphone array ... if you did it right, with the right playback equipment, that might give you the ability to "move around" inside the listening space. I'm not sure if it would really be any easier than just doing multiple X/Y-pair recordings from different parts of the concert hall, though.