Compressing while tracking is used a lot. As Dean sez, it helps to know the voice/instrument/musician. But even w/ a artist you know it isn't wise to overcompress or EQ or anything. But you can flatten out a sound a little - help w/ really loud hits and bits. A little going in means you don't have to work the compresser as hard during mixing. Just as using eq filters - esp. the grunge in the bottom - can help get a more solid, workable signal to mix with. The key is not to overdue it, since any damage you do can't be undone.
Dean,
the Tone Beast is a very cool preamp. Very flexible, a choice of op amps, output transformers (or none!), as well as the in/out gain staging. I just used it as a DI on a bass this weekend and it was lots of fun. I got a little growl w/ the staging (and you can get a lot of distortion), and a nice thick smooth bass - all from the same instrument and player on different songs. While no signal element alters the sound in a major way, in combination ... you can get a lot of different tones out of it. If you get a chance, check it out.
The review should be out in the next Tape Op.
@