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I'm soon recording some crowds for a game, for battlefield and running scenes happening outdoors.
Any advice on how should I do it, regarding mic setup and placement, post and etc? I have available a studio stoned-room and a dryer one.
I've once recorded a crowd for a similar battlefield situation. I had 15 men in a 15m by 5m relatively dry sounding studio. I recorded everything with 2 mic setups. A. xy B. spaced omni. Placement of the men and mic's was along the long wall, i don't remember exact distances.
I actually layered these recorded 3 times to get this big attack feel to it, with all men screaming their lungs out. It was great to do, just take care to bring a lot of water for the voices. And maybe get someone to do the engineering so you can direct the sessions.
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I recently recorded a bunch of battle cries for a production of "Richard III" with an Audio-Technica BP4025 into a Sound Devices 722 at 24/96k (in case of pitch shifting). I was in the theater space where the play was being put up, which was a large black-box space that was a little live but not horrible. I set the mic up about 10 feet in front of the 15 actors, who were standing in the center of the room. I recorded passes of constant screams, but also short yells, which when put together made for a more dynamic sound than just the constant scream by itself.
Prior to that, I'd been using a big group scream I built in 1998 out of several takes of 5 guys around a stereo pair of 414s (through a Mackie board to DAT) in a moderately dead tracking room at a music studio. I must have used the "Big Skreem" build on a couple of dozen projects since then.
What period is it? And are they angry? I'm sure you could layer small groups of people say 5, and build it up, to create large crowds, people in foreground and background. And there are battle re-inactments around the world if you're super dedicated.
have you considered recording the crowd outside? This naturally depends on your requirements for the game and what you are looking for - one of the advantages of recording outside you will be able to multi mic at long distances and you'll also get authentic environment reverb to boot. Down sides are or course the control and the background noise - the sound of airplanes in Roman times is probably not what your looking for :)