Best power amp for Avalon Opus Ceramique


Trying to downsize my system to a speaker/power-amp/ cd-player set-up (with digital volume control e.g. Wadia 581, Audio Aero Prestige or EMM Labs).
Which power amp (ss or tube) in the range 5k-10k is recommended to use with Avalon ?
Will ICE powerd amps like BelCanto, JRDG or NuForce work as well ?
frankpiet
regarding class D amps: I found a combination which works with the Avalons(at least with my Opus Ceramique): Kharma Matrix 150. Tiny little boxes with a very very nice, neutral and highly detailed sound.
Have you now had enough exposure to the boulder 850 mono to make comparisons with Ayre V1xe and pass 350.5. I ask because i'm considering using one of the above mentioned to drive Lipinski L707. C5xe and Aesthetix calypso. Any thoughts??