The other thing I really am noticing about those measurements, aside from how the FR undergoes a 27 db drop relative to target between 1.5 and 2.5 khz is the mismatch of the channel volume. Not only are they badly mismatched but the one that's louder than the other switches with FR. Most egregiously, from 3k to 5 k the left is around 3db louder than the right, then it switches from 5k to 6 kg and the right is about 3db louder than the left, and then it switches back from 6k to 7k and the left becomes somewhat louder, and finally from 7k to around 9 k the right is again louder. Combine this behavior with its atrocious group delay and distortion, and it has to image like absolute crap. I don't think anyone will recommend pairing this Yamaha "flagship" with an A16 Realizer anytime soon.
Once again the target market for this kind of thing is obviously not the seasoned audiophile, audio engineer, or musician. A shame that newbies get conned into buying stuff like this when there are literally any number of great headphones that can be had for l.t. $500. A major audio company like Yamaha really deserves have its brand tarnished for bringing something like this to market and charging $5000 for it. Just shameful and greedy. And ultimately it's them biting the hand that feeds them, so it's breathtakingly stupid as well.