I hate the word laid back to describe them. I kind of consider them to be more polite, meaning they don't bombard my ears with noise I don't want to hear. They seem to take the slight edge off all my harsh/fatiguing tracks. Less so with my new Magni for whatever reason. They're very musical and despite what someone just said, they do get me into the music. Maybe not in the way a Grado does, but that's sometimes a good thing. They're engaging, but yet I could still fall asleep while listening to them if I wanted to. Makes no sense at all right?
I don't know why, but this pair I couldn't describe as being dark at all. My last two pairs were and sometimes it was only noticeable in gaming for whatever reason. I've tried all pairs with the same equipment too.
One thing I noticed is that female (or any) vocals on this pair are not recessed/distant or anything like that. I wouldn't say forward, but it's possible. My HD-598 does seem to have more forward mids, but only slightly. I think this HD-650 has some slight forwardness in the upper mids, but not enough to be annoying. This one also has more controlled bass than my HD-600. No mid-bass hump at all that I can detect with this pair.
I never thought I'd ever be saying it, but I love this HD-650 more than the HD-598. The 598 does have a larger soundstage though. With the Magni is pretty close in size possible. Haven't checked yet..