The Eikon is a good choice with regards to the neutrality and deep bass. Sound stage is OK as well, though not what I would call exceptional- but that’s not what I personally look for (that’s what I use open-backs for). But it is a phenomenal headphone, and if you are OK with 300 Ohm resistance (you have HD-800s, so why not?) then it is a great option. ZMF is selling their last new batch of them now for $1300, I think- then you’d get the lifetime driver warranty as well.Right on re: detail and soundstage. I have HD800s and just want a closed-back alternative. I could probably use more bass though as my last few headphones were relatively bass-light (HD800s, AKG Q701, z7m2)
Do you have any recommendations in such a context? Closed-back, heavy EQ is ok, good soundstage, good/deep bass, good detail, good isolation, don't care about the power requirements. I think I tend to like "neutral" heaphones overall, as "warm" just means different EQ and I can always get from "balanced" to warm if I feel like it. I wouldn't mind spending $2K if that's an endgame-level device. Idk more, but again, I am considering Stealth, so..
The other note I’d add is how a Beryllium driver might work well for you. The ZMF Verité Closed is known for its sound staging despite being a closed-back, and meets your other criteria also. It is more expensive, but also more detailed- a lot more.
Same with the Focal Stellia, though it is considered to be a little warmer and less capable of projecting a large soundstage. I have one and really like it, but again- sound stage is less of a focus for me.
Last option you could consider is the Audeze LCD-XC: Less expensive, better isolation, but heavier. More neutral, loads of detail, and amazing planar sub-bass. Easier to drive, as well.
I would add that I don’t EQ, so you will need to check reviews for how these four options deal with EQ. I think Resolve has EQ’d the Verité Closed and Stellia, but I could be mistaken.