I finally had the opportunity to listen briefly to the AKG K812. I own the Q701 and generally like the AKG sound so was interested to finally hear these.I work near the Harman Kardon "flagship" store in NYC. Unfortunately, this store did not have available for demo their "flagship" headphones for at least 6 weeks since I had first stopped by hoping to listen to them. The other week they finally had them in and one of the salespeople invited me over. All I had for a source was my Iphone 5s, but at least it had my personal test tracks albeit in compressed format. I asked if they could hook that up to an amp. The one salesperson said he could plug my Iphone into one of the H-K amps they had. He was clearly having some difficulty with this and finally another salesperson said "Oh, you can just use your phone; they will work fine." I didn't want to force the issue and was, in fact, interested in how they sounded out of a phone, but would have also like to hear them amped as well.
I generally liked what I heard on my brief listen. They did not seem particularly neutral to me, but that did not seem to necessarily be a bad thing. They definitely had way more bass than my Q701, to the point that I think they went from an underemphasis to an overemphasis. Not that I didn't like it, but it just didn't seem neutral to me. The salesperson said they were going for more of "fun" sound with these as opposed to the "classic" K/Q7xx line. While I don't think he really knew much of anything I did personally agree that it seemed like a more fun sound, which surprised me because I thought they were trying to go for a higher (and higher-priced) reference sound. In that respect though, I did see how maybe what they were trying to do was have a sort of HD800 sound with a little more warmth and less demands made with respect to upstream gear. I know from actual experience that the HD800 is pretty unlistenable from a smartphone. But my impression with the 812 is that while it would probably scale somewhat I was getting a decent enough sense of what these cans were about just from my phone.
The K/Q7xx line have a wide soundstage but it pretty much goes from far left to far right. I like it, but understand that others feel this is not natural. The K812 also had a very big soundstage but was very different. The best I could come up with was it was if I was wearing a large space helmet and the sound was being piped into the helmet and the sound was kind of all around me in a sort of globe shape around my head. Certainly a different and impressive (in the sense of making an impression, but not necessarily good) presentation. I am not sure if over time I would really dig it or just find it weird or fatiguing. But in my 20 minute or so listen I quite enjoyed the soundstage.
I did try a bunch of different tracks in different genres. I was surprised that I did not find the treble exceedingly bright even on test tracks that I find somewhat painful on my Q701. Given what I had read I thought some tracks would be unlistenable but I did not find that to be the case. Sonny Rollins' St. Thomas, one of his great tunes, is hard to listen to on the Q701, but did not bother me on the K812. Now maybe it had to do with the weak amping of my phone. Or maybe the increased bass let me listen at a lower volume so any bright treble was less noticeable. I didn't notice any distortion that others have noted, but I am probably not sophisticated enough in these things to pick up on it unless really egregious.
Comfort for me was less good than the Q701. I really like the auto-adjust on those and they fit my head really well. The K812 seemed a little loose and unsecure even on the tightest setting, and I don't feel like I have the smallest head either. Now, I was standing in a store. Perhaps, sitting in my home this would be a non-issue. And of cou
rse these are significantly heavier than my 701s.
Overall, I enjoyed my short listen. As much of an AKG fan as I am though I think I would have a hard time paying $1,500 for these. The store said I could purchase and have a no questions asked 30-day return if I was unsatisfied. But I would not feel good about that unless I was really serious. At $1,000 +/- I might have as I could see these as potentially being a worthwhile upgrade from my Q701 in that they still have the same large (but different) soundstage, while adding the warmth that was lacking in the Q701 (and which for certain genres was not a problem, but for others is).