Bass Texture - Other than being a little less hefty than I'd like (just a little), the extension was very, very good, and the texture was simply breathtaking. Felt like I heard the spit on the lips of the tuba player. Spectacularly clear.
Bass Slam - Holy moly! These hit amazingly hard. Yes, the lowest two octaves are a bit shelved down, but my goodness they rock!
Midrange - Hey! How did these people get into my house! The realism with the SR-009 is incredible! (Hang on a sec, I've got to write a sentence without and exclamation point.) The seamless coherence between mids and highs deliver a stunningly realistic presentation I've simply not heard a voice so convincingly real on headphones before. Stunning! Simply stunning!
Treble - Damn! I'm running out of superlatives. I'm super sensitive to trouble in the treble, and I'm floored by being able to hear a strong sense of speed and treble energy without it sounding strident in the least. The sense of coherent high frequency sound is extraordinary; everything is more than natural and organic, it's simply sounds like you're there. Wow again!
Dynamics - Come on! When are these cans going to show a weakness? On the other headphones the Flamenco guitar strums are punchy, but here it's as if you can hear each string of the strum individually hit, and then add their voices together with a musicality of impact I've heard on no other can.
Imaging - Finally! (Still using exclamation marks, though.) The 009 is bested handily with regard to imaging by the HD 800. However, these are no slouch, and great depth and width are realized; separation and depth are very good. Without the HD 800 within arms reach for comparison, I would find these a spectacularly immersive listening experience.
Read more at https://www.innerfidelity.com/content/comparing-world-class-headphones-stax-sr-009#wWQHmp0tmTOc0gyQ....
I had got a fever after reading above article.