well, i have been spending considerable time with the c700 lately and can say that i like them much more than i did at first. my first impressions were that they were too boomy. where the atrio created thunder, these created clash with no resolution. i listen to pretty much only trance and trance relatives like faithless and some ambience etc.
after a few days, i created a new eq and my ipod touch which has tremendous bass has been able to handle the denon phones. the bass with a little reduction in eq is now controlled and instead of uuuumph, i can hear rtrtrtrtrd where the bass actually has a texture. finally i thought. naturally, the mids are a slight notch above the atrio m5 and with my new eq, the rather neutral sounding ipod touch has gained some wetness.
as for isolation and walking about - I am in a winter wonderland now which will be under snow until next may or so. i must therefore wear multiple touques (as it blows snow horizontally the entire winter) and these are very annoying in cold weather. they sound good, but as they are so large, they get pulled from my ears at every movement of my head and i have to angle my head in order to enjoy the music.
the highs are quite nice and i find them - as dynammics to be much freer of sibilance than any armature driver - for me, the e500 and um2 (the two more controlled armatures) even produced far too much sibilance and pain.
after liking them quite a bit, i decided that my atrio which as warrior said, were getting less time should also get a helpful hand again. funny, i could not take them off (partly as i hate to put them back in - takes forever). they haven't trouble with bass boominess in my ipod touch with trance like the denons do, but i kept the same eq and found to my surprise that the mids actually came forward a bit. i did boostt sme mid frequencies and to my surprise, the a5 responded well. naturally, the slightly recessed bass setting i gave them toned down my favourite aspect of them: the wonderful bass - the likes of which i have not heard before, but they held well and overall, after factoring in the isolation, ease of inseration and overall sound: i do prefer the atrio m5.
the only thing that will not keep me coming back is that... well, they take forever to insert and in the cold, i hate to take them out and then try to put back frozen grapes into my ears. the denon are a wonderful phone and they have proven along with m5 that my place is with dynammic in ears or iems and that sub us 200$ phones can kick the hell out of the likes of um2 and e500 for my needs.