Best tube amp for Wilson Watt/Puppy

That is easy. I would suggest either the Lamm ML3 Signature amp, (uses the Russian Ulyanov GM-70 tube) at $139,290.00 or the deHavilland GM-70's using the same tube at $9,995

Find a good, used pair of these Audio Research VTM 200 Monoblocks.

http://iar-80.com/page3.html

I used to use a Krell KSA 200s sometime back with my Watt Puppy 6s (with the new tweeter) and although the system is not the same, it probably sounds somewhat similar to your current setup. If so, there is plenty of room for improvement on the amp side.

I'm using a pair of YBA Passion 1000s now and the difference between now and with the old KSA200s is night and day. Yes, it's not tubed (but it has a tube-like sound) and the price is more than your stated budget. Just letting you know that there's plenty of improvement waiting if you make the correct choice.

The CAT tube amps have tremendous synergy with Wilson speakers. In fact, the guys at Innovative in Manhattan said that the CAT monoblocks paired with X-1's yielded the best sound they have ever gotten out of a two-channel system. That said, and while they are unusually well built, those amps can be quite finnicky, and expensive, to own - they require very carefully vetted output tubes, which CAT charges outrageous prices for, for reliable operation due to the hot-rodded circuit. Both the monoblock and stereo versions of the amp can found for less than $10,000 used. I believe a new stereo amp (the JL-2) goes for +/- $14,000 new.

I think Wilson is voiced and optimized for Audio Research.