I have a classe 201 driving Martin Logan SL3's.My pre-amp is a BAT VK 3.This pre-amp has made the sound much more liquid and relaxed,in fact She Who Must Be Obeyed has given me a 10pm curfew otherwise I could listen until midnight every night.Before I had a cp35 pre' and that was grainy,coarse and somewhat harsh.In fact I'm thinking of buying another Tube amp to drive the panels and the CA201 just for the woofers-but then I'm sure cabling will be an issue