I use the Peavey Pro 500. This is one sweet amp. It's usually run at 4 ohms through either a SWR Goliath Jr. 3, and SOB, or a 4 ohm Aguilar GS212. It's a very loud 350 watts at 4 ohms. Before this amp, I was using a Peavey Max preamp with a Carvin DCM2000 or DCM1500...I loved this setup but I feel the Pro is a much better amp. It has a tight sound, it sounds like it has a built in compressor. I love the parametric eq, I'm able to dial in the tone I have been looking for. I have compared the tone to the Sunn/Fender 1200....but IMO it sounds tighter. Recently I used it with (2) 4 ohm cabs and got the maximum power from the amp, 500 watts...definetly very loud! I didn't even go through the pa for this gig. For basses, I use a Fender P/J or a (just aquired!) Fender Highway 1 jazz. You can't go wrong with this amp, yes it's more expensive then other Peavey amps, but it's well worth it. I think I'm still the only person on TB with this amp.