Belles upgrade??

Never heard the Belles amp, though I have read the Pass Labs amps are on another level. Currently own a Pass X150 one of the older ones, but see no reason to upgrade with my Supratek preamp.
I had a Modwright preamp before the Supratek, comparable with a different flavor. I would think the Modwright would pair well with Pass
go for the .5 or .8 series which are suppose to be a little warmer.

Hi - Thanks for the suggestion, will consider. One of the biggest curiosities I have in this thread is whether I would get big gains in performance by going with similar monoblocks as opposed to stereo amp? Klaus from Odyssey states you get biggest performance improvement with his gear by going to monos versus upgrading his stereo amps.   

It's mainly in the power supply. Two separate and independent ones in monos generally perform better.