Richard,
At under $4000 used, you should listen to the First Sound Presence Deluxe Mk II. I wouldn't say that it beats the CAT in every respect by a long shot, and it is a different sound, but it is significantly more transparent to my ears than the CAT. CAT is the king of smooth, full, rich sound. I don't agree with Sardonyxx that the Ultimate can sound lean. My guess is that if it sounded that way, he listened to one with either the "wrong" tubes in it or some other component was responsible. On the other hand, the F.S. is detailed and on some material can come close to be on the border of delivering too much information. But with the right tubes, it is excellent at imaging and allowing you to locate vocalists within the soundstage. It does this far better than CAT's, which also throw a huge, wide soundstage, but the instruments are kind of blurred within the stage,at least relative to the F.S. The F.S. may not be a good match with the Merlins, which I have listened to at several shows and have also found to sound very detailed. F.S. has very good bass, and fantastic dynamics, the dynamics even being better than CAT when the right tubes are used, and the CAT has very excellent dynamics. The bass of the CAT is unsurpassed to my ears. It is just gorgeous, deep and full. I own both the CAT and the First Sound 4.0, which is one level up from the normal unit. If you go up the line of F.S. preamps, supposedly it gets better and better. A used F.S. Presence Deluxe Mk II should be considerably less than $4000.00. I'd have to check the current price list, because I remember that a new one was about that price. I think that I bought my F.S.P.D. Mk II 4.0 for about that price, used. Other units you should listen to are Herron, Ayre and Emotive Audio. There may be many other good choices at this price point, but I'll stick to what I have heard and have liked.
