It's my turn the chime in, I suppose. My impressions are the same. The M80s were hands down winners. I am very lucky to have absolutely no room for tower speakers in my current home so I can be very happy for Ken without the slightest hint of jealousy or upgrade-itis on my part.
I'll comment more about the wiring thing. Before we started the listening session, I was pretty sure the M3s would sound the "least best" - meaning they'd be good, just not as good as the others. When the M50s turned out to sound pretty nasal and anemic, especially in the bass area, I started to suspect something was wrong. I suggested that Ken switch the M3s and the M50s on the back of the Marantz. That was when he discovered the M50s were wired out-of-phase. Now it made complete sense why the M50s had been sucking (and simultaneously blowing, actually).
After the wiring was remedied, the M50s popped back into focus. But the not-so-little speakers that could -- the M3s -- still seemed to best them on punchiness in the bass area. It could be the difference in crossover and cabinet volume. I'm not sure, but there was that little extra magic in the M3 sound that just wasn't in the M50s. Now if we only had a tube amp and some Oil Impregnated Metallized Polypropylene capacitors to swap into the crossover... THEN we'd have the perfect speaker.
(hi 2x6!)
About the possible difference contributed by the separate components, all I can tell you is that when playing tracks from the iPod, the M80s sounded less better than the other speakers than when we played tracks from the CD player. Since the M80s are more revealing, it seems logical that this was the case.
