Time to resurrect this old thread...
My wife "insisted" that I pick up a pair of closed headphones (after I sold off my D7000s) as my current three: T1/HD800/RS1i 's all leak copious amounts of music to listen to when she and the kids are in the room.
I was "given" a budget of $250 by the boss to meet this requirement and I was able to get an outstanding deal on a new set (Consumer Premium edition 600 ohm version).
They arrived this past Friday and have about 70+ hours on them and I really, really like'em.
These are definitely not the 80ohm Pro bass canon versions, they are surprisingly balanced (especially for a closed headphone) and sound very similar (to my ears anyway) to the DT880/600 ohm version.
From memory, the DT880s had a slightly bigger sound stage and had a more airy affect (not surprisingly for an open headphone), but the DT770/600 have slightly more bass impact (which I like) and the treble doesn't seem as bright (they do seem slightly warmer overall). And as closed headphones, they actually isolate better than any full sized headphone I've heard and rival some of my IEMs in this regard.
Comfort wise, I am super happy (
) that they are as comfortable as the DT880s (which along with the HD800s are the most comfortable headphones I've ever had on my head). Their construction is classic beyerdynamic! Sturdy, well built and light on the head.
I do prefer them quite a bit to my (now sold) Shure SRH840s. They are way, way more comfortable and no where as hot on my head. Sound wise, they are more revealing (very close to the DT880/600) and offer better sound staging, detail retrieval, and bass control.
As mentioned, I am surprised just how similar they sound to the DT880/600 and do seem slightly warmer (which again is a good thing for me).
So if you're looking for a good closed headphone and have a pretty good tube amp and are a fan of the beyer DT880s, I would seriously recommend giving the DT770/600's a listen.