Bel Canto Ref1000 MK2 Or Ref 500m ?

The two amps use totally different ICE modules so you would expect they sound different. If you haven't alreadt done so, check here for info on the two modules. Plenty of specs for you to go through but IMO the newer ASX2 series modules used in the 500M have better specs.
BTW I am currently using the 500S amp in my system with good results. Although I have used several amps (300S and 300M) with the 200ASC module, I have not heard the Ref 1000 which uses the ASP series modules.

I have the Ref1000 mk2 and they sound phenomenal. Effortless dynamics, bottomless power reserves, articulate delineation of every note. Deep lows, smooth mids, and clean highs. Never lose composure in the most complex passages you can throw at them. Run cooler the louder you play them and idle at only 15 watts each. They take a LONG time to break in (I honestly think over 1000 hrs) but when they do, you get an incredible amp setup that can compete with much more expensive amps. I advise setting up dedicated outlets for each. I am running 20 amp circuits for each with 10 gauge 30 amp copper wiring with no power conditioner (I have surge at the main). These babies sound better than ever now (with 50 amp peak draw, they need some serious power supply). Who says you can't have too many watts ;-)

I love the Bel Canto Ref 1000 Mk.2, now renamed Ref 1000M. I have reviewed it for PFO:
http://www.positive-feedback.com/Issue43/bel_canto_ref1000.htm

I have heard the Ref 500M at shows at significant length, but not in my system. I have heard unconfirmed reports that the Ref 500M may sound even sweeter than its more powerful brother. As far as I know, Ref 1000M is driven by ICEpower 1000 ASP modules, while Ref 500 M may contain ICEpower 500 ASP modules, which yield up to 250W over 8 Ohms.

Unfortunately the BelCanto web site does not seem to mention the modules contained in their amps. I know my info on Ref 1000M is correct, but I am not completely sure about Ref 500M. I will call Bel Canto tomorrow and will find out.

G.

Guido, The 500S uses the newer ASX2 module. I was curious so I opened mine up for a look. As for the 500M, I would be interested to know. It would be nice if Bel Canto were a bit more forth coming with this info on their web site.

I think Guido is correct about the type of ice module in 500M. Keep us posted!