I'm starting to see what people mean when they say these cans are picky with source. I was listening to some Prince (Prince), David Byrne (Look Into The Eyeball) and The Beatles (Magical Mystery Tour) last night, and I was completely amazed by the overall sound including the bass. Quite frankly, I was floored by their overall sound, including the bass, and am now starting to wonder if I was too hasty in thinking these cans lack on bass.
Another thing worth mentioning is that I think these cans are approaching 100 hours of burn-in, which might have something to do with the increase in bass. The reason I think this is that when I listened to The Beatles (again, Magical Mystery Tour) last week I am sure it didn't have as much bass, and as a result wasn't as good as when I listened to it last night.
One thing I am certain about is that the Q701s sound amazing with the above albums.
Just got these. Maybe 5 hours in I didn't think they lacked bass THAT much or were "muddy" when under amped as some would say.
BUT I just got a cheap "crappy" Bravo V2 (plenty of noise sure) but the bass is there. Amped on Bravo V2 they sound better than my X1s. damn.... listening to Phil Collins Face Value right now on the Bravo V2 and a UCA202 dac they sound amazing.