Our first step in mixing vocals in Pro Tools is to compress the vocals. Let's take a listen to the files are naturally, with no editing or processing whatsoever. The first thing you'll notice is that the vocals are quite a bit softer than the piano track. For the sake of editing, let's go ahead and move the fader down on the piano track so that the vocals are slightly on top of them.
Play back the files again with the piano brought down. Compare the vocal sound to that on a commercial recording you like. Notice that the vocals sound very "raw" in comparison? That's because they're not compressed.
Compression does two things for vocals. One, it can help a vocal track stand out better in the mix by sitting better within the overall mix itself. By compressing, you're making sure that the loud and soft parts of the vocals are even. Without it, the soft parts will get buried in the mix, and the loud parts will overpower the mix. You want the vocals to have a nice, smooth sound in the mix. Second, compressing brings out the tone of the overall vocal sound better, allowing it to make a better impact.
Let's click on the insert area above the track, and insert a basic compressor. Select the preset "Vocal Leveler", and look at the settings. This is a great preset to help you with compressing vocals. If your singer is very dynamic, like the one we have in this recording, you'll want to bring the "attack" - how fast the compressor kicks in on peaks/valleys - a little lower.
Now, you need to compensate for the volume loss you incur when you compressed. Anytime you bring a compressor into the mix, you're changing volume, and you need to compensate for it. Move the gain slider up until you're satisfied with the added volume. Listen to the mix now. Notice that the vocals lay much better in the mix?
Now, let's move on to the next step.