I have had my 3803 clip off to the protection circuit once before with my M60's, VP150 and QS8's. I am not sure what volume setting I was at, but I believe it was around 0.
I am not sure I understand the whole ohm rating efficiency issue anyway. You mention driving difficult speakers at the same time as saying a lower ohm rating. I thought a lower ohm rating meant "less" resistance. So I have never quite understood why less resistance would be more difficult for an amp, common sense would dictate that it would be less work on an amp, but clearly I am missing something here.
I also thought that the M80's were supposed to be very efficient, hence the 4ohm rating. I would also like to know what you find out, and hopefully understand speaker ohm ratings and their effect on an amp better.
