You don't need that kind of power to drive the MG12.Especially for the room size your putting them in..It's not too much ..but overkill IMHO.Checkout some of the Carver ZR series amplifiers if you just got to have all that power. Maybe a Forte 4 Class A amplifier or someting along the line. There's a couple guys on this forum that use these with Maggies.Also there are some guys on AA that are trying Set tube amps on their MMGs.That should tell you something.
a couple of questions about maggies
i was wondering if the magnepan 12 speakers are set up for bi-amping (2 sets of posts per speaker)? would two b&k st-140 amps power these speakers well? i believe that amps are rated at 105wpc @8ohms, but magnepan says their speakers are 4ohms. if bi-amping is possible, then each speaker would get a total of 210 watts. is this too much? if biamping is not an option, then what amp would you recommend in the $500-$800 range? my room is 11'x14' carpeted with one side open to a balcony. thanks.