easiest solution in my opinion (without wiring in new switches or anything into the amp) would be to find the volume you like for jamming, go back to your volume knob and while retaining your original settings turn up just the volume that you like for soloing. once you get this volume, keep it there and learn to control it with a volume pedal. buy a nice pedal and the control will actually be pretty good. dunlop's pedal is pretty reliable as far as having a good volume when the pedal is horizontal, and raising just enough for soloing when the pedal is fully depressed forward. if you want it permanent, just wire a signal booster or dB booster with a toggle switch or button inline with your volume knob inside the amp. hope that helps somewhat. oh, if you have a line 6, just save it to some extra channels and control it off the footboard.