Wanted to leave my thoughts here for anyone interested in upgrading from their Arya. THes Unfortunately, the Susvara was outside my budget... The notes below are all in sequential order of when I tried them.
Arya v2: Amazing soundstage and speaker-like presentation, but not without it's flaws. Treble had a noticeable peak and vocals were a little blurry in some respects. Wanted to see what the HE1000 series could offer, so I sold them.
* Source at the time was the iBasso DX312 dap with a Norne Silvergarde after-market headphone cable.
HE1000SE: My first major upgrade over the Arya and into the next price bracket of 2k+ headphones. First thought is "Wow these are detailed". Technicalities and resolution is through the roof. The sheer speed, force, and accuracy of the bass, without any fostex-like bloat, blew me away especially! After the honeymoon period though, I realized how bright the treble is and how the tuning of the midrange was off. Maybe it was too warm for me?... The treble peak is what killed it for me though. It was a higher frequency than the Arya v2 but more distracting to my ears. While the soundstage didn't feel as grand as the Arya v2, it was still a sufficient size. Eventually, I decided to sell them for the HE1Kv2.
* By this time, I reterminated my Silvergarde cable for ZMF headphones, and ordered a Norne Draug Copper for the Hifiman's
HE1000v2: I read a lot how the tuning on these are better, despite the less impressive technicalities (but still better over the Arya), and I would have to agree here. The treble is the smoothest here, but still very detailed - easily my most favorite approach to this frequency range. Soundstage is larger than the SE, and maybe even the Arya v2. The reason I say maybe is because the midrange is drier, less warm, but also closer, so it doesn't feel as deep to me. I did eventually find the mids a little too dry, but it depended a lot on the recording. The biggest killer though was the bass. As mentioned in reviews online, it's not bass light, but the dynamics are very lackluster. It's just so... soft. Even the Arya v2 was better here and for the price, I found it pretty disappointing.
* At this time, I upgraded my source to include the Cayin C9 portable amp. Huuuuge improvement, especially with the Class A / NuTube selections.
(This is off-topic, but sorta relevant at the same time - feel free to skip...
In the interim, I also upgraded my IEM to the Theiaudio Monarch mk2. For $1k USD, it was the best money I ever spent these past few months. Easily the best enjoyable tuning I've heard in a long while. After hearing these, I decided the rollback all my headphone upgrades and return to the Arya. Even the ZMF Verite I purchased, after selling my Fostex and Sony Z1R, are being sold. At this point I decided to prioritize tuning over technicalities, and save money in the meantime)
Arya SE: Instead of going back to the v2, I decided to try the SE despite the mixed impressions. These feel like a baby HE1KSE. The tuning is similar from my memory, but it's more linear in the treble and midrange, which is really good in my book. This has my favorite midrange presentation of all the headphones here - not too dry and not too warm. The bass is definitely punchier than the v2, but loses that unique speaker-like feel to it. The soundstage doesn't bother as me as much as I thought it would, but more so the presentation that made the v2 so unique. I do like the Arya SE though and don't see myself selling for now.
In the end, I feel the Arya (v2 or SE) is the best value headphone on the market, especially if you grab an open box deal. If you want to upgrade from the v2, I would say don't. There's nothing really out there that is a "direct upgrade", only more like a side-grade. If you want an upgrade from the SE, then the HE1KSE would be a perfect upgrade if you don't mind the treble or can EQ. I really wished I heard those headphones through the Cayin C9.
