Have to agree with Puddles on the mesa, great sounding amp,new they list for $2495. Had one driving a pair of proac studio 150 for over a year, and the sound was absolutely beautiful. Had to let it go recently due to the purchase of new Nagra monoblocks. With the Mesa, as a bonus(and that's why integrated amps were originaly refered to headphone amps), it doubles as one of the best headphone amplifier out there, using its full 16 tubes. If you've never liked listening to music through headphones, it's because you've never tried it with a quality amp, match the Mesa with a pair of grado RS1 or Senheiser 600(which is not uncommon to find selling new for around 350$) and you're in audio nirvana in no time, and for a very small amount of money. I use to have guilty pleasure using my headphones and not having to worry about... are my speakers in the right location... should I add some more tube traps in the corner? And don't even think about lying down on the sofa!!! For the money it packs a lot of value;you get a headphone amp, you get to choose between full pentode operation,2/3 pentode 1/3triode(my favorite),1/3 pentode 2/3 triode(works very good for older jazz vocal recordings) and you can choose between either zero negative feedback or three settings of feedback. In ending this I have to say that the amp is also a visual Knock-out, The gold and grey version with those 16 tubes glowing,is absolutely gorgeous! Good luck in your quest!