Comparison REVIEW! Stax SR-X9000 vs. SR-007mk1 Audiophile Headphones

Systems used and compared:
MacBook Pro (Apple Music Lossless) + Schiit Yggdrasil (LIM) / SMSL M400/M500 + KGSSHV (500V / Carbon) + Stax SR-X9000 and SR-007 mk1 Headphones

All my SMSLs are delta-sigma DACs, whereas the Schiit Yggdrasil is a R2R type DAC.

Corrections to this video:
1) X9000 has good slam (due to the fast transient response) but less thickness and impact vs 007mk1
2) The X9000's ability to make the headphones disappear are a result of its neutrality AND fast transient response (not transient response alone).

Additions to this video:
1) X9000's bass balance and sub-bass are great but don't have the same amount of presence and thickness vs 007mk1's. Overall, the X9000's bass is superior in character vs 007mk1, although sometimes I wish for more thickness in the X9000's bass and mids.
2) If the X9000's vocals / mids were a little more forward and thicker, the X9000 would be superior to the 007mk1 in every way.
3) With the KGSSHV amps, I think most people would prefer the 007mk1 over the X9000 because of the more recessed mids on the X9000. Although the X9000's mids are more recessed, it sorta makes up for it by being more detailed and neutral.
4) It's likely that a powerful tube amplifier (BHSE or Woo 3ES) would smoothen and thicken the X9000's mids and make them more pleasing, possibly definitively better than the 007mk1s.

What the Schiit Yggdrasil (LIM) fixed for the X9000 that was mentioned in the prior videos:
1) John Mayer - Gravity: his voice doesn't sound like it's coming from the floor / ground anymore
2) No more mid-bass bump on the X9000
3) Sounds no longer feel like they're playing in a vast space; the floor, room, and space are more clearly defined

Songs referred to in the video:
Post Malone - Circles
Ariana Grande - Positions

Music genres used in comparison:
Vocal jazz
Acoustic vocal songs with a few instruments (e.g. Adele)
Orchestral / large symphony
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