I'll make another series with an old Elaine Elias CD. Too much bass on the Barber CDs.

Ahh screw it, I will use Rage Against the Machine. Too lazy to find CDs.

Basically as you go down in frequency, you will hear less "air" (has nothing to do with sizzle) to the point where you feel unsatisfied. This certain point, where the difference is most obvious, would be your treble roll-off point. Mine is around 17kHz with the STAX 007.

Basically it's not so black-and-white.

not uploaded yet...

UPDATE: uploading now. UPDATED

• "Purrin's Hi-Freq Hearing Test.zip"
• Sting - Englishman in New York
• 20.5k down to 13k. Some music players cannot handle below the tracks with a cut-off of 15kHz.
• Listen to percussion, high-hats, and cymbals
• Use a comfortable listening volume!
• Make sure your headphone has enough treble extension! It may not.

The 17kHz point is where I feel there's something missing. I do feel the full 20.5khz sounds best, but I wouldn't bet $100 between being able to distinguish between that and the 18kHz file. Shit, my hearing must be better than I originally thought. I think I need to post on Head-Fi that my hearing goes up to 21kHz. I must be a genetic freak. Probably those ageless asian genes. Or maybe people with STAX hear better.

i thought the last one sounded best as well. most noticeable in the bells, but after 18k it was hard to actually tell to be honest or don't even know if i actually did notice anything. i think it sounded like the bells at the beginning sounded to have bit longer amount ''air/decay'' at 19khz over 18khz. i'm using my DF's atm and i think there limitation is around 18k. might just be my hearing as well. not sure. too late right now as well to use speakers.

Probably those ageless asian genes.

could be. i notice it mostly though with males....well on my side of the family. i don't know about my hearing though. i just know i look much younger than my age physical appearance wise. 

As far as phase shifts, remember that we are not listening for quality in terms of best, but for "air." Brick wall filters will cause phase changes, but these usually amount to harshness. I don't really like test tones because people end up hearing distortion artifacts (which are much easier to hear) instead of the pure high frequency signals.

This test taught me that if a set of headphones starts rolling off at 17khz, it doesn't matter at all. 

Going from the 18khz file to the 17khz file is where I heard a real solid and obvious difference in the sound of the cymbals themselves but the 17khz one certainly didn't sound bad at all.  I thought I heard a difference in my general sense of air and spaciousness going from the 19 to the 18, but I need to try it again and it's the kind of thing that's hard to tell whether my mind is playing tricks on me.  Because it's not changing the sound of any instrument, it's more a subtle feeling and nothing that can be pinpointed.