Hello
I was able to compare the Odin mk1 (first production batch) with the Odin mk2 (second production batch).
Odin mk1 owners do not have to be disappointed because for the moment, the mk1 Odin sounds better than the mk2 for the simple reason that one is perfectly burn-in and not the other.
According Pierre, you must count 150 h of running so that the mk2 Odin sounds with the same fluidity and smoothness than the mk1 Odin, see perhaps with even a little more transparency by virtue of its internal wiring for Litz wire (for the Odin mk2).
For the moment, the lack of burn-in of my mk2 Odin (compared to my mk1 Odin) is characterized into a lack of fluidity and smoothness, and a certain relative harshness.
In short, to any new owners of the mk2 Odin, don't consider your new Odin mk2 right away; It deserves several dozens of hours of running to begin approaching the potential and the wonderful sound of a perfectly "burn" Odin (more than 50 hours see more than 100-150 hours of burn-in are necessary; you will enjoy then, a lot more, the better fluidity, smoothness and even greater listening pleasure: you will spend of a (relative) rough sound to a perfectly smooth sound, both soft, natural, living, dynamic and accurate.
Moreover, the sensitivity of the Odin mk2 and mk1 is really very close to, and limited by the precision of my microphone and measurement conditions to +/-0.5 dB for a test of the 4 drivers Odin to my disposition (mk1 L/R and mk2 L/R) on a frequency 500 Hz test, for the same position of my amplifier volume knob (see photos at the following link:
http://www.homecinema-fr.com/forum/post178909617.html#p178909617)
Otherwise, I'll have to retrieve my Viva Egoista 2A3 amplifier, next Thursday, with the power transformer wired on the mains 240 V (instead of 230 V).
Otherwise, for memory, I also could compare the Vali to Odin: both are very great headphones, each in their technology (dynamic for Vali and planar for Odin).
To summarize, I quite agree with the grizzlybeast test
http://www.head-fi.org/products/kennerton-vali/reviews/16049 ; the Vali is a super dynamic headphones, characterized, immediately, by its dynamics and its very impressive bass; it is an headphone very lively and fun (and pleasant) to listen; this headphone It is a kind of super HD-650, in much heavier, but best in everything; In addition, it is easier to amplify.
About the Odin, it is one of the best planar at our disposal, even rivaling the Abyss (best mids and trebles, sound more natural); It is a kind of super HE-6, better in all and infinitely easier to amplified.
Compared to the Vali, the definition of the Odin's mids is best: it passes, somehow a HD-720p definition at 1080p (by analogy to video); Odin's bass, although it is slightly less powerful and slightly less deep than the Vali, is equally striking and more textured (more defined); Odin's treble rises a little higher than the Vali.