Almost as much mids as Sennheiser.

Yeah these are treble heavy and sibbilant as well, so definitely don't get them if this bothers you.

I have 660S and recently tried some Bayers to see if they have the bass I want for more thumpy electronic/pop music because of course that's what the HD6 series lacks. I landed on the lower end 770 Pros (I got the black Limited ones) and I have to say I'm quite happy. They're well tuned despite being a bit more recessed in the mids, and I can deal with the high treble when it's in those electronic genres because it's not overbearing there. So now I have closed backs with more thump and treble for electronic, rap and pop and my HD660S for guitar driven music like metal and rock. I'm good with this setup, and I think having the two pairs gives me a lot more precision than having just one endgame set. But we'll see, as these things never seem to stay stable for long.