megabigeye
Headphoneus Supremus
Getting the headphones to seal less well will reduce the bass significantly. Do you wear glasses? That does it for me. I don't know your preference, but for me this reduces the bass so much that I won't wear the PM-3 while wearing glasses of any sort.Are there any earpads for Oppo PM3 that can reduce bass? Are perforated? Or hybrid velour?
You could experiment with breaking the seal, maybe put something like soft earplugs between the pad and your skull, changing placement of the aperture.
Or maybe a pad made of perforated leather would work? Dunno, never tried it.
I think your best bet is going to be EQ, though. Unless you really want to go all in with testing different pads and/or experiment with breaking the seal, it's mostly going to be a craps shoot as to whether or not it'll match your preferences.