Yesterday I got started with an idea for how to create a fully functional and totally separate monitor console inside a front of house desk (digital). Today's trick is a little simpler and something you can implement on stage or in the studio even with an analog desk.
Compression is a powerful tool. While it controls level it has the possibilities to effect the tone of a signal as well. Just slapping a comp on an insert is only one way to do the job. Having a completely separate signal chain that you compress the bejeebers out of and then blend in with the uncompressed signal gives you much more control and keeps that control on the console where it's an easy reach instead of in a rack of outboard gear.
Let's break it down simply. In a DAW you just double the track and process the second one separately. On a digital console you go into the routing matrix or menu and send one input to two channels. On an analog desk you have a couple options. Either use a Y cable to split the mic coming in, or go from a direct out to the line in of another channel.
Once you've got your two signals it's time to get crazy. The first channel might need some compression on it just to keep it in line. So go ahead and apply some as needed but don't get too nuts with it. With the second channel you can really go crazy. Compress with a high ratio and low threshold, just be careful to adjust the attack and release so it doesn't sound completely flabby.
Once your settings are dialed in you can turn up the original channel to add more volume, or turn up the "smash channel" to add more fatness. You can even go a step further by putting a ducker on the smash channel and side chaining it to the unprocessed channel. When the vocal is loud, the smash channel goes away, when it quiets down it starts to come in, making everything nice and fat.
Our friend Eike in Germany goes so far as to have his first layer of faders completely doubled in the second layer on his digital console. Page two is all smash channels and at the press of a button he can fatten up any channel he likes with a subtle fader move. We'll have a little more from Brother Eike tomorrow where he takes the concept even further.