Hi Brandon G,
As Jakewash has pointed out, Denon's amplifier sections of their AV receivers are robust and able to drive the 4-ohm M80s without current limiting, overheating, or shut-down. You can see a recent review of the Denon AVR-989 AV receiver in the January '09 issue of Sound&Vision magazine. As the reviewer, Dan Kumin, notes, the AVR-989 "also supplied generous current increases into 4-ohm loads" with no difficulty. Increased current flow through the output section are what 4-ohm speakers require of amplifiers, and which often prove to be too much for some other brands of AV receivers, causing them to shut down.
Axiom also recommends Sherwood Newcastle to drive the M80s. We sell those on-line. Even the least expensive Newcastle receivers will drive the M80s with ease.
Regards,
