Hi Micah,
I would point out here (as I'm sure JohnK will) that any AV receiver run past its output limits will shut down, even if it is rated to be stable with 4 ohms.
You have a huge room, many times larger than the average, which puts a lot of stress on the relatively modest amplifiers built into a 7-channel AV receiver.
Used in a typical living room of about 2,100 cu. ft (about 19 x 13 x 8), which the Axiom listening room emulates, the Sherwood R772 or even the $300 stereo model will drive the M80s to very loud listening levels--louder than I like, without overheating or shutting down.
No, it won't begin to reach the extremely loud levels some of my colleagues prefer, +100 dB SPL, for which only separate power amplifiers are recommended, but used within its limits, the Sherwood Newcastles have robust sturdy amplifiers that have never had the problems with 4-ohm loads associated with some other brands, including some models of Emotiva.
Regards,
Alan Lofft
