Axiom uses the mechanical roll-off of the 6.5" in the M3 which is widely known. It wouldn't surprise me if the M80 took the same approach as well with the 2 midranges. Like any choices in speaker design there are trade-offs.
That was noted in the 1K loudspeaker blind listening test.
The M60v2 employs 4 drivers with a 1" titanium tweeter, 5.25" midrange and two 6.5" woofers. They are triple vortex ported (2 rear / 1 front) with a claimed extension down to 37 Hz (-3dB). The tweeter has a 2kHz 12dB/octave HP filter while the midrange has no crossover at all relying on the natural acoustical rolloff of the driver (12dB/octave) and small sealed enclosure to provide more bass output above the tuning frequency of the ports.http://www.audioholics.com/reviews/speakers/floorstanding/2010-1k-faceoff/1k-faceoff-comparisons A high pass filter for the midrange driver wouldn't effect bass output at all. If there were a low pass filter it probably would effect it, but I would prefer a little less bass output compared to driver breakup. Do the M80's have the same crossover as the M60's, where they may be driver breakup at a high volume setting as well?
