I'm new to bass guitar and played my first full room last night. I've got a PF500 running through a GK410 neo. I'm using an SR1400 Ibanez bass, no effects, just bass into the wireless receiver. At the practice studio, which is small, I'm doing ok volume wise but last night I seemed to lack headroom. My stage volume wasn't great and I would start to distort when I tried to get good "punch". I use my amp as a monitor, the other guys have in ear monitors so we don't have anything pointing back at the stage. I've got two different options right now, one is add an extension at 8ohms which would take me to a 4 ohm load. That ups the PF500's output correct? I've seen some people having cutout issues running 4 ohm loads with this amp but I've had this thing cranked at practice and never had the red light flash on me. My other option would be something rack mounted. My guitar player gave me his X2 wireless and a tuner which are rack mounted and there's space for an amp in the case. That would enable me to just have a rack and a cab to haul around. If I did go rack mount what would be a good option for a head with plenty of headroom and reasonable, $5-700 range? Any advice I can get from the pros out there?