Check out the stickies for compression tutorials. One of them talks about vocals specifically.

However, to "smoothly blend" vocals with the track, I imagine it's more the EQ than compression, although compression would play a part.

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One always has to remember these days where the garbage pail is, because it's so easy to make sounds, and to put sounds together into something that appears to be music, but it's just as hard as it always was to make good music.
- Robert Moog

Ratio depends on the singer.

Threshold depends on level the recording was done at.

Attack depends on the singer.

Release depends on the music and what role you intend the vocal to play.


Seriously, there is no right answer. Learn what each of the controls do in practise, and apply it to the material you're working with. Generally, you'll want to go for a fairly low ratio; a threshold low enough to 'control' the dynamics, yet not overcompress them; a low enough attack to capture the fastest of transients, yet not blur them out completely - you may in fact want to make the vocals more articulate; and a fairly low release for a more direct and punchy sound, or a higher release for smoother, laid-back vocals. It all depends.

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Put an end to the loudness war. Don't limit or compress your mixdown until mastering; leave the master channel alone.

Contact me for mastering.

it depends... if the song is supposed to be dynamic, then i'll compress it just a little bit to control the levels a little. nothing too hard, maybe like 3db of gain reduction. but if it's more of a full on pop/diva vocal, then i'll most likely slam it pretty hard with a compressor and a limiter at the end to catch the few parts i didnt catch.