Those AKGs will represent a totally different sound and you will probably start appriciating good quality mids and highs listening to these. I've heard the HD272 which is pretty similar in response and signature and boy those are closed versions of these headphones but yet they sound very open so I can't imagine how "open" the open-back version of these sounds like. Very airy, vocals/acoustic instruments were such a pleasure to listen to for the price.
Goldenears have measured the AKG 240 if you're interested to see, what draw my attention especially how "natural" sounding it was rated to at a rating of 4 there and that's something I can agree with on HD272, very natural sound to it.
Edited by RPGWiZaRD - 3/28/14 at 8:09am