For me personally, this is a 24/7 decision for the HD800s.
I love these headphones, especially for its, in direct comparison, more natural sound, the significantly larger and more finely staggered stage, its comfort and, in my opinion, it is less amp sensitive than the focal.
It even works excellently in connection with your Fiio K9pro.
It’s a bit dependent on the music genre, but for classical, jazz, blues, and folk, it’s hard to find significantly better headphones that aren’t significantly more expensive.
Having said that, I have to say that good biocellulose drivers just got me hooked and triggered a craving for more, and longer listening sessions.
This is the reason for the Auteur recommendation, since the Atrium might then go beyond the price range.
To me, a good biocellulose driver simply sounds more powerful, basses get an enormous volume and a naturalness that no other type of driver can reproduce in this way.
Without “bothering” the other frequencies.
In the middle frequency range there is an unbelievable naturalness,
In my opinion, both E-Stad’s and planar drivers only have advantages in the high frequencies, which make the sound appear more airy and a little more precise.
I then often catch myself feeling the sound of these headphones as weightless or too thin.
Well, a matter of taste.
P.S.:
I‘m Not a Gamer