I currently have a pair of Bowers & Wilkins P7 and Master & Dynamic MH40 sitting in front of me. I think I like the MH40 better, but I'm curious about the PM-3. How does the PM-30 compare to those headphones?
I've never listened to the MH40, so I can't comment on that, but I own the PM-3, H6, and just sold off a B&W P7 two nights ago. I like them all for what they are.
- The P7 is the most V-shaped with big, sometimes boomy, bass. It has the smoothest/silkiest sounding treble of the bunch (in my opinion). It also scales wonderfully.
I sold it off because I own a TH900, which is similar in signature.
- The PM-3 is more balanced than the P7, with tighter bass that still reaches deep (really deep when hooked up to a good amp), but not as rich as the P7. These are very similar to the HE-400i I think, with a more smaller, more closed off soundstage... like being in a small dive bar rather than a concert hall. They scale very great as well.
- I'll toss in an H6 comparison while I'm at it... The H6 is mildly V-shaped, but not really warm. On its own, the H6 sounds fantastic, but both the PM-3 and the P7 edge it out in terms of sound quality (richness, clarity, overall coherency). I kept it, however, because it easily beats out every other choice in the "full size, over-ear, luxury portable" category in terms of weight, portability, and size on head.