Thank you Henry, you are absolutely correct. I have since called Bel canto and asked further information about differences between Ref 500M and Ref 500S.
* Both amplifiers make use of the ICEpower 500 ASX2 modules in bridged configuration. They do not use ASP series parts.
* the Ref 500M uses additional power regulation over the 500S, hence it actually yields slightly higher power: Unless I am getting this all wrong, approx 250W over 8 Ohms for Ref 500M and 200W over 8 Ohms for 500S.
* the BC Ref 1000M is the only Bel Canto amp to utilize the older ICEpower 1000 ASP module, because there is no ASX2 module to yield the power rating of 1000M.
* Unless the very high throughput of 1000M is required for proper control of particularly power hungry speakers, the Ref 500M may yield the most refined sound of the lot.
* Both amplifiers make use of the ICEpower 500 ASX2 modules in bridged configuration. They do not use ASP series parts.
* the Ref 500M uses additional power regulation over the 500S, hence it actually yields slightly higher power: Unless I am getting this all wrong, approx 250W over 8 Ohms for Ref 500M and 200W over 8 Ohms for 500S.
* the BC Ref 1000M is the only Bel Canto amp to utilize the older ICEpower 1000 ASP module, because there is no ASX2 module to yield the power rating of 1000M.
* Unless the very high throughput of 1000M is required for proper control of particularly power hungry speakers, the Ref 500M may yield the most refined sound of the lot.