Sonic Defender
Headphoneus Supremus
As a previous owner of MDR-1A, the MDR-1A doesn't even came close M1, so the best bet will be M2 from my own opinion. Ever consider B&O H6?
I didn't it hear the m1 that way. I went to compare the M1 directly against the 1A at my audio shop and I have to admit the M1 was rather dull and flat I thought through my rig. I hear the M2 is much improved. We all hear different obviously, but to my ears, remove the bass bloat potential of the 1A and the sounded better than the M1. Just an opinion, not fact of course.