How is this possible? I drive my Sennheiser HD600 with the E12 and even on low gain setting, I never need to go past the halfway mark. Anything more gets uncomfortably loud. HD600 is rated at 300 ohms

Quote: wow. I think I've rarely seen M-80 being described as horrible.  M-80 is my portable headphone and I use Sennheiser HD 600 with Fiio E12 amp at home and I still don't mind the sound from the M-80.

I have M-80 and they sound very good for the price. In terms of isolation, I think many people like to exaggerate the effect of the side vents.  It may be a fraction worse than a fully closed back cans, but it still isolates very well.  At a decent listening volume, I can't hear most...