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Old 06-13-2011, 01:51 AM
Pokiehat Pokiehat is offline
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Quote:
Originally Posted by goldhedge View Post
I recorded my fiddle for a CD and it sounded thin and tinny. The engineer tried placing the mic in several different areas. In the end, he used 4 mics and mixed it down to one stereo mix.

There was a mic behind me, one really close, and two more further out front.

Why couldn't one also mic the guitar up close and also mic the room sound to get the desired effect?

To my way of thinking, it's the harmonics that make up the sound of an instrument. The ear is very good at assuming the sound and it 'makes up' for the differences in tonality. A recording does not. Just listen to your own voice and you'll see what I mean.

By placing mics in different areas of the room, they each pick up a different harmonic tonality and 'report' their findings to the machine. Blending the different inputs creates what the ear already 'hears'.
It doesn't work like that. How does one mic "the room"? To most closely approximate the sound you hear from your position in the room, it would need to be a binaural recording (with both mics in your ears). The sound of your fiddle from this position in the room will be different to someone standing somewhere else in the room.

What your engineer is doing is building an illusion of sound coming from a real space by using 4 mono source recordings - 2 near (dry), 2 distant (wet). It doesn't have to be completely authentic. It can in fact be highly unrealistic so long as the listener doesn't cop the illusion.

When you mix multiple sources like this, destructive phasing is something you need to be conscious off. There isn't necessarily anything wrong with the mic placement, since it may just be mixed poorly. Or the opposite may be the case. You should read up about destructive phasing and do a few sound tests with simple test tones to get an idea of what happens when you phase shift and sum to fewer channels (hint: same source recording x2 with 180 degrees phase shift + summed to mono = total destructive phasing. No sound at all).

One solution to fix periodic destructive phasing, is to add more phase shift. You will never stop periodic destructive phasing but you can shift the destructive part into a less significant part of the sound and the additive part into a more significant part. Its difficult to explain but when you see it in practice its an easy thing to demonstrate. It isn't easy to control though.

Last edited by Pokiehat; 06-13-2011 at 01:56 AM.
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