Hi, Since some years I've got this 2nd hand Randall RB500. It sounds realy great! I'm surpriced that it's not known around here. I've omned and played a Carvin PB300 (mosfet), Hartke 5000 (tube/ss preamp, ss poweramp), Orange AD200B (fulltube) and now the Randall. This one is a tube preamp and mosfet poweramp. I was searching for this combi. A full tube wasn't tight in the lowend. And a mosfet is soundwise close to a tube amp. The RB500 has also a dirt channel, gritt from the tube! So, any others here?