>> but the M3 has a bit of a hump in the 100-150Hz area which gives an impression of more bass

Yep. The M3 sounds much fuller than you would expect given its size and driver complement. The M3 (and presumably the W3) is a nice design -- the bass bump is big enough to make the speaker sound much larger than it is, but not enough to distract from the sound.

M60ti, VP180, QS8, M2ti, EP500, PC-Plus 20-39
M5HP, M40ti, Sierra-1
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