On Tue, May 04, 2004 at 10:57:21AM -0700, Mark Knecht wrote: > > Suppose someone turns up the volume for more harmonics. > > But what harmonics? Where do these come from, and why? The kind of brick-wall limiting and gain-stage-hammering that people do to get "loud" mixes introduces significant harmonic distortion. That's "where". I can't tell you "what", I don't know the characteristics of the distortion technically. As for "why"... > If I record a > violin correctly, why do people think they need more harmonics? Wrong choice of instrument ;-) Classical engineers tend to lean toward neutrality and accuracy in their recordings. Now, proceeding as if you'd said "guitar" or "drums" ... ;-) I have a (completely untested) theory that part of the reason is due to the distortions that happen in the ear at high listening levels (mentioned earlier in this thread). At rock-band volume, your ear adds harmonics and maybe even does some kind of dynamics compression (it seems that way to me, though I've not heard anyone else mention this effect). Record the audio with a highly accurate, low-distortion system, play back that same audio at home listening levels, and it literally does not sound the same. It sounds "smaller", not just quieter. This may be due to the absence of the harmonics created in the ear by the very high level of the original. So, some deliberate harmonic distortion is used to counteract this effect, and make the music subjectively "big" even at low volume. > Just a > strange hearing thing that tends to favor having them? Possible, but > also possibly black magic. I guess I'm too 'old school'! ;-) I suppose you use only measurement microphones too ;-) Really it's nothing new. Plenty of "old school" pop/rock/blues/etc engineers pushed their analog tape and analog consoles hard to get some soft clipping, which both introduces harmonics and acts as a sort of peak limiter. Now we're still doing much the same thing, only we're using high-tech brick-wall limiters. I suspect those old-school pop engineers discovered tape saturation and related techniques somewhat by accident. Nobody thought it out ahead of time, they just noticed it made some records stand out from the crowd, maybe carry a bit better on AM radio, and the next thing you know your kids are watching "duck-and-cover" films in school. Oh wait, that was a different arms race ;-) -- Paul Winkler http://www.slinkp.com
