Used pass labs X600 monoblocks or new X350. There are a couple of pair available on this site.
Are you close to a Pass dealer? Check out an X250 & an X series pre-amp. I don't think the Wilson Benesch speakers you have need more power than that. I've heard they're very well made but bass-shy. A local here in Phoenix tried the Linn Klimax monoblocs & the latest Rowland monoblocs - neither got those speakers to give the bass he wanted. You might want to add a musical sub like a REL or a Bag End..
Hi Thsalmon - Danielk141 is right. The WB's don't require much more than 200 or 250 watts. They can be bass shy with low power amps but like I said, 200 - 250 solid state amps really drive the WB's to a level where a great majority of the bass is NOT an issue. Of course a REL would help no matter what.
I am curious to know how you are connecting your speaker cables. Tri-wire? jumpers? Factory plates?
I have used Electrocompaniet, PASS, Chord, McIntosh, Cary, Krell, Accuphase and Plinius with these speakers.. but my favorite thus far has been LAMM M1.1's.
In all honesty - the WB's are very neutral and while every amp has its unique character, a WB system seems to benefit more from a good preamp and cabling. I really hate to say but amps can be secondary to a fantastic TUBE preamp.
Ask around about Supratek Cortese or Syrah preamps.
The XA777ES is good - gets better with age and can be modified to have tube output and power supply - but I am sure you already know that. The CD12 would be the holy grail for your system and would be utterly magnificent with a Supratek Cortese, LAMM M1.1's and the cables of your choice... See you've gotta play with interconnects. KS is good but there might be better matches available as your system evolves.
Tsalmon: Even @ $10k, the type of music you listen to PRIMARILY (and hence, judge by) could be the decisive factor in choosing the amp.
If classical, Pass (BUT see Bwhite above), YBA Passion, Symphonic Line (the big Kraftquelle integrated) for ss, Lamm, Tenor, Atmasphere, KR, for tubes.
Caveat: some of the above is based on extrapolation (sorry!), I have only listened to your speakers with the Symphonic Line and the Passion combo.
Bwhite and others have your speakers & can help with their experience -- but Marakanetz makes a meaningful point!
Linar Audio 250. This unit is made by Victor Sima from SimAudio. He claims that this is his best amp to date. If you go the www.linaraudio.com you can read and see the quality of this amp. It will out perform amps costing 3 to 4 times their price. Detail, air, bass, decay. If you audition one, you will be stunned!
The Pass Labs X600 is absolutely the best power amplifier ever made. Its ability to provide detail, definition, explosive impact, but still provide dark quietness, warmth, smoothness, (without the harshness of a Krell) is unsurpassed. Tony Cordesman (a reviewer for Absolute Sound Magazine uses a pair in his reference system.
Lucius Morris, Dynamic Sound Audio
I have been enjoying your conversation, however it makes me feel alienated. Is Mark Levinson a thing of the Northeast? I think (know)they are great. I listen from classical to Graham Parker. Mark Levinson is where I would invest my money and my audibility.
Mark Levinson is good for "those of us who know we are above the rest" (in hifi).
McIntosh is good for the "nostalgic"
Krell is good for the "nouveaux riches"
The rest compares themselves to the above to achieve legitimacy.
If you are looking for pure music reproduction, well...
I've listened to the new Linar 250i amp with the new linar preamp and i can tell that they both are a must to consider when searching for very top quality gear.
They cost $10750can. (US$7690) together and they can easily
be compared to much more expensive gears.
I bought the Linar 150 in 4 channels configuration
with the preamp in order to bi-amp my BESL S5 full range speakers that i'm presently building.
The 150 is presently used on some small french "Pierre Étienne Léon" monitors and using a DVP-S9000es and the sound and stereo image is incredible, the quietness in the background of the music is first class, i even enjoy my cheep $100 Kenwood digital tuner now with this amp and preamp !
I've replaced a good Copland CSA-28 hybrid integrated amp
and the Linar have much more life in the sound, much more powerfull and the pleasure to listen to music is increased
a big step up. I had first class service from the Linar team