I have the M80’s in a similarly sized room. I use them for stereo only. The room is 26’ X 32’ with vaulted ceilings about 22’ high. I’m driving them with a H/K 7200 that’s rated at 100 X 7, all channels driven. I read somewhere a while back that this AVR actually puts out closer to 145 watts. I wanted the M80’s because I like lots of base and the M80’s were supposed to have the most base in the Axiom line. I also looked at other speakers including B&W and Paradigm, but the M80’s got my vote. My receiver goes from -80 db to +80 db. I can not crank it past 0. They are simply way too loud. FYI, I’m a bachelor and the only reason for me to not crank up the tunes, is certain imminent hearing loss. These things can play incredibly loud with unbelievable clarity. They could fill a gymnasium, and sound very good with relative ease. That being said, I didn’t need them for volume, and neither do you. I suspect that the M60’s would be too loud for my application too. Do not buy the M80’s because you think you might need the volume, you will NEVER play them to their full current carrying capacity. Not unless you are already legally deaf. They have twice as much woofer surface area, so in theory, they should have more base than the M60’s, but I’m no expert and can only speculate. I did end up buying an Outlaw subwoofer to fill in the low range a tad. I’m still not sure if I like it or not. I have it set to the minimum X-over at 40 and about mid way with the volume. Some CD’s it’s simply too much thump, some older classical rock CD’s, I turn it up to around 80. I’m still experimenting.
To summarize all this babbling, if you insist on getting the M80’s, get a receiver that will drive them. Axiom will only recommend H/K, Denon or NAD to drive them. I was told to look for 100 watts minimum in either of these three brands, or go with real high end stuff with a much higher price tag. But if you plan on buying a sub, then I would stick with the M60’s.
As far as sound, I personally think the M80’s sound is more akin to the Paradigm Studio Ref III 100’s than the 703’s. Possibly somewhere in between the two. Not as much low end as the 100’s and a tad more detailed, but not as detailed with a little more base than the 703’s. Better, tighter mids than both. How’s that for comparison?
