Sounded to me like he had a bias towards planars and against dynamics in general and certain dynamics in particular. How you can base your 'disappointment' in certain headphones based on that is ridiculous. Go listen to an AKG812 yourself if you want to see what it sounds like.
You don't always need to hear something. The K812 has been universally panned as inferior to the HD800 by a large margin. K812 is supposed to be a the flagship AKG has to offer for PROFESSIONAL use, providing the best accurate sound. To me that means like the HD800 it should measure very well. AKG K812 is $1500!!! I would expect you get much better performance than the K712 for the extra $1150 since market price on the K712 is much less than the MSRP, but K812 price is pretty firm on $1500. Is HD800 worth that much too? Dunno, up to the listener, but at least you have the comfort of knowing, you're getting the very best dynamic headphone technology has to offer right now. With K812 you're getting a K712 with more magnetic flux density, 3mm bigger.
I have no interest to hear the K812 since I already have the K712, if I want to hear something else, it will be the HD800 or top level planar later.
I don't quite understand the whole reasoning behind analysing all these graphs and measurements, I've heard a fair number of the TOTL headphones and I can easily say that the "distortion" of some headphones and all these alother weird arbitrary tests and benchmarks mean nothing.
Edited by SSandDigital - 6/20/14 at 1:30am