I have my power amp bridged using both channels to drive a single cab from a single preamp, but I've been thinking of adding a second preamp for a mic and using both channels of the poweramp seperately. That's a workable deal for my QSC RMX1450 isn't it? I usually play the bass through a single 15" avatar cab, but I have a 210 cab I could hook up if needed. If I get the preamp for the vocals, would either of my cabs work well for PA duty? Or both of them together? I don't want to have to buy a whole new batch of stuff if what I have will get me most of the way there.