this past wed. I sat in with a friends band using my K&K rockabilly special(w\two channel pre-amp) equipped urb and my amp...while the sound was great I still could not get the volume(w\o feedback)needed to be heard(the amp was behind me)..that is until my amps power cord(for some strange reason)kept coming loose and killing the power,so I plugged directly into the p.a..low and behold!! no more feedback and tons of volume.the p.a speakers were on tables out in front of us and a little volume coming from the moniters(and I could hear myself better than with my amp) and the sound was KILLER.my question is..could it be speaker placement? would it be better to kick my 2x10 back like a moniter and face towards us or maybe from the side(like side fill moniters)to avoid feedback.can anyone shed some light on this strange but wonderful phenomenon(sp?)or should I just leave the amp home and let the p.a do all the work..thanx in advance.