My main concern is to not blow my PAs. I'm in a jam band and our vocalist likes to shout. A lot. I have a mic plugged into a mixer which goes to the amp which goes to two 15" Seismic Audio PAs bridge-style. Out of fear of blowing my PAs, I only turn the amp input sensitivity to about one-third of it's full potential, but we could use more volume, especially during shows. I guess I'm wondering how much risk of blowing my speakers is involved in cranking the amp input sensitivity and lowering the mixer's gain and send knobs.