I will repost and state that the CAT probably works well with any very high quality, neutral solid state amp. Besides the Plinius which I mentioned previously, I have a Pass Aleph 4 which I like very much, but always felt it was a little shy in the upper mids, even though it exceeds the Plinius in bass and treble extension,detail and soundstage width and depth. I recently went from Telefunken 6DJ8's (Ecc88's)in the CAT to Tele 6922's (E88CC's). What a difference in treble clarity, detail and extension! Bass extension and weight is also improved. It may actually be too much of a good thing. Soundstage is deeper. With one pair of tubes the dynamics are outrageous, but only when the music calls for it. The other pair has less dynamics than even the 6DJ8's but it brings along a refined sound that the 6DJ8's didn't have. I had long thought that I had found the limits of the capabilities of the CAT, but I now realize that I hadn't. And who knows if I have at this point? This is beginning to sound like a tube review so I am going to stop. I would say, like the previous poster that the CAT will give you anything and everything that your tubes and upstream components can muster. Every new tube that I have tried in the CAT has made an instantly recognizable change in the sound. Certainly, certain tubes sound better than others, but any component which reveals so easily the slightest changes is truly exceptional. It is the job of whatever amp you choose not to lose any of that bass or treble extension, detail, soundstage or harmonic structure. The Pass Aleph 4 does that and with the right tubes in the CAT to bring up that upper midrange "softness", I feel that I am now achieving sound of a very high calibre.
