One of the biggest problem with a program as powerful and flexible as Mainstage is balancing your levels to make them even from patch to patch. As a professional Mainstage patch designer, it's still one of my most difficult tasks. Here are 7 tips for making sure your levels match up:
1. Play at least 7 notes at the same time as loud as you can. Make sure that they peak at no louder than 0 db, since this will keep you from clipping.
2. Change the velocity curve. Each instrument does this differently, but making your velocity curve more "flat" will help keep you from sudden spikes.
3. Use an EQ to get rid of troublesome frequencies. Always reduce, don't ever boost.
4. Turn down, not up. Make sure you don't boost your faders too high- it's fine to keep things quiet.
5. If you have to, use a compressor. This is my last resort, since most leveling compressors will degrade your overall dynamics live.
6. Review your levels before you play live. Sometimes things will sound different onstage, and last minute tweaks make a big difference.
7. Be conscious of whether you're running mono or stereo. Each will have different effects on your levels, especially on patches with a wide stereo field.