Best power amp for Avalon Opus Ceramique

Frankpiet:The best cable match between these two is probably Transparent audio XL series.The best I heard was the NBS, but the cable costs more than all the gear put together,which in my humble opinion was a skewed way of thinking.

Hello Frankpiet and Sphere,
I have the Opus Ceramique along with X2.5/X150.5. Most of the cabling is NBS Omega I (speaker / power & pre) and the Stealth Indra for Cary 306 SACD & pre-amp.
I compared the NBS Omega I for source/pre with the Transp.Balanced (make sure it is the newer generation, the MM-technology) and the Transp. had firmer grip with the bass, more resolution and better soundstage; NBS was a bit lusher. This just proves that although some cable company stress the synergistic effect (certainly the case with NBS Omega I saying you should buy it "as a system") it pays to mix and Transparent does a good job for source/pre, however it is very very expensive. At the end I settled with Indra which was in-between.
Finally, here in Europe you will see the Opus Ceramique mostly paired with Hovland or Pass along with NBS or Transparent, but that might be the case because of the distributor ("Active Audio"). But it sounds great.....
cheers and good luck

I am sorry that I cannot answer your specific question regarding the Opus Ceramiques. I do want to say, however, that I have found the Jeff Rowland 302 amplifier to be far superior to previous Rowland amps I have heard, and that I find it to be very natural and involving. Not a surprise to me that someone else might find the opposite to be true, though, given the many variables we all deal with in evaluating any given component. Just MHO (of course).

Mikefi: your thoughts about Active Audio are absolutely right. They combine the brands (Ayre, Hovland, Pass, Transparent and Avalon) in their show-room set-ups. The sound in most cases is very good -although the very expensive (to expensive for me) combo Boulder 1010 + Boulder 1050 + TaraLabs Omega / Zero + Esoteric X0-1 Ltd. is far superior.
Nevertheless I once had a Pass X 2.5 pre and replaced it with an Ayre K-5xe which I found to be superior to the X 2.5.
I do not know the X 150.5 only the X 350.5 and find it a mighty fine product (its on my short-list) if I don´t decide to keep my excellent Ayre V-1xe. I believe Pass power amps are much better than their pre´s.
The Rowland 302 mentionned by Jfz is a mighty fine product but in Germany rediciously expensive - around US $ 25.000,00.

Frankpiet:
If you own an Ayre V-1xe which I think is one of the best amps on the planet, you should concider K-1x and D-1x, with or without "e". The K-1x is a very neutral preamp smartly built and forever lasting and the D-1x is the cleanest player I'm aware of, far better then any Wadia. To me Wadia is a bit colorating and lacks some drive.
The only minor thing (which I actually like) of the V-1x is it's slightly emphasis on the base, so you have to match this with a leaner speaker (if you have the same experience and taste of course).
For cabling I like NBS most because it is neither dark nor bright. So it tells you what is wrong in the chain. Very useful as an audiophile if you want to improve your system.