the jazz authority; random dubiously zappy rants about 'the musicians music'.: Audio Compression & you

Wednesday, May 11, 2005

Audio Compression & you

Let's make this quick and simple. The more you compress your audio, the more you degrade the audio quality. The bit rate refers to the amount of audio info in an audio file. If a tune has a bitrate of 96, it's at about FM radio quality. At 120 Kbps, it's said to have CD quality audio by some, but I say that's a bunch of crap. Most tunes are ripped at 120, but I can definately tell the difference between that and 160Kbps, whick is my standard. 196 isn't too much (the higher the number, the less compression, the larger the audio file and the better the sound). At 200+ it's basically pointless to compress it anyway, but to each their own.


graypencil said...

yeh .. all well and good for your own use ,,BUT:

if you don't use some "selective" and unobtrusive compression when you master you CD for airplay , it'll come out like cotton candy on the air ..and by the time the stations usually ill-maintained broadcast limiter runs your CD thru the ringer, you'll wanna shoot yourself!

a good limiter/compressor can be your friend!

Cameron W said...

Well, that's compression in a whole other context. My post was aimed at newbies who want to rip or download tunes and don't know how to find tracks with decent audio quality. You're talking about more advanced concepts in compression.
I've noticed using AUDACITY that it's best to balance track volumes in a rough mix first when mastering, then I'll mix down, and tehn I'll normalize the entire stereo track. This works for me. I tried normalizing the individual tracks first and then mixing down, but I lose subtle changes in dynamics.

Also, when recording in the studio I don't like to have a lot of compression set on my horn. It helps on stage when playing in loud settings, like a rock band, and I don't have to worry too much about my tone. In a quiet jazz setting, I prefer to have no effects whatsoever on my mic, And if it's a small room no mic at all!
If one does use a compresser/limiter, there are a couple of great ones on the market that are reasonably priced. Just remember; clipping doesn't need to happen!