Ok so, the conclusion to my comparison between the HE1000 V2 and Arya (v2). I actually am still undecided between the two, but mostly for financial reasons. I just feel weird owning a $3000 headphone, but oh boy, does it make me think it's worth it.
I'll just compare the key differences between the headphones here, without going through all the categories a typical review does. The only note I'll say about build is that I prefer the build and comfort on the HEKV2. I find its lower clamp force easier to wear for long sessions.
The main difference, for me, is presentation. What blew me away about the HEKV2 is the stage. It's significantly wider than the Arya, and more spacious all around. With the Arya I sometimes get the feeling that sounds coming from immediately left or right are too close for comfort, like coming directly from the driver and even a little behind my ears. That never happens with the HEKV2. Everything is to the side or in front, with plenty of distance and pinpoint imaging. It lays the music out in front of you like a neatly arranged banquet of sounds. However, what the Arya gives in its closer sound (though still quite spacious), is a sense of immediacy of the music. You feel it more palpably. The example that made this blatantly obvious was "Time" from the Inception soundtrack. With the HEKV2 I was listening to a musical composition. With the Arya, I was having an experience. You felt the crescendos, not just heard them. Imaging is less precise and soundstage is closer, but it takes you on a journey in a more visceral way.
Then there's timbre. There is a clear difference. Voices have more warmth and body on the HEKV2, and in most cases where the Arya made voices sound unnatural, the HEKV2 is able to fix it. Not in all cases, however. There's still a bit of unnatural brightness on some tracks, but I blame that on the mastering. Guitars and other acoustic instruments similarly have a very present "core" to the sound that almost perfectly represents them as they are in real life. A classical guitarist whose playing I know very well, Matteo Mela, was shockingly accurate. I'd never heard his guitar playing rendered so accurately on any sound system. It was like realizing "Oh yeah, that's what Matteo sounds like!" It does timbre better than an HD600...which I guess at 10X the price should be expected. The Aryas are good, but noticeably "planar" and a little thin. Textures comes out better, and sounds appear more detailed (more about that later), but the tonality is off. I prefer the HD600's timbre in that case.
Bass time. I wasn't initially a fan of the bass on the HEKV2, but it really grew on me. Not as tight and impactful as on the Arya, but actually more in quantity, and very soft/pillowy. Almost tubey. Compared with the Arya though, it lacks texture, feels a bit bloated, and isn't as immediate. But oh boy...what a comfortable feeling. Listening to Colplay's "Rush of Blood to the Head" (the song) was a trip. The bass was exactly where it needed to be. Foundational, deep, and perfectly integrated yet separate in the mix. The Arya was missing just a bit of the quantity needed IMO. Still, on other tracks, I preferred the tighter, more punchy bass of the Arya. John Scofield's "I Don't Need No Doctor" is one example. Also Jeff Beck's "Come Dancing." They both just slam a bit better on the Arya. I get into the groove more easily.
Finally detail. This is a strange area. I've heard people say the Arya is more detailed, and others say the HEKV2 is more resolving. Yes. Here's how I see it...the Arya is a more detail-forward headphone. It pushes detail at you more. Bass texture, vocal subtleties, micro-details, they're all pushed to the forefront of the mix, often in a more unnatural way. But strangely, I noticed many more new things in tracks with the HEKV2 than with the Arya. I think it's the more resolving driver overall, and because of its competence, has to force detail at you less. It's all there, like the trailing ends of tones and small nuances of a plucked guitar string, but it's not forced at you. And because it's not forced at you, it appears significantly more natural and actually easier to pick apart. Overall the detail is less compressed and "in your face." It took me a lot of listening to hear this, though, so I understand the confusion around it. But in the end, I do think that while the Arya is very technically capable, the HEKV2 clearly has the higher resolution.
So in the end it's actually kind of a tossup. Do I want a softer presentation, with more spaciousness, warmth, and cleanliness? Or a more visceral feeling, closer in, but slightly artificial and edgy? The HEKV2 is clearly a more technically capable headphone, and now that I've heard its soundstage I can't un-hear it when I go back to the Arya. But the Arya is not too far behind, and for a far more reasonable cost, though I got my HEKV2 used at a good price as well.
I hope some Arya users get the chance to try one of these bad boys out someday. I was doubtful of Crinacle's "S-" tier rating (just behind the Utopia and Susvara), but I'm not anymore. It definitely deserves it.