My top priority is clean sound, it's true. My Explorer sometimes reminds me of listening to cassette tapes. Fixing the hiss would go a long way. I might see if I can find my old Etymotic P->S cable and see if that makes it more listenable.
As to the frequency response graphs, I'd be very interested in seeing yours. I was thinking about putting together a rig at my home office for doing that myself. It'd be fun to use test gear that's made for MHz sampling for simple two channel audio.
A few people have mentioned hearing a "hiss" now, but I have tested every earphone I have, as well as many o don't during CanJam, ranging from BA to dynamic to planar headphones, and I have not ever experienced this. I ha EA tried these tests with multiple units as well, and also have a few of our partners running the tests as well with the same no-hiss results.
Can you please let me know what earphone and which track you are using? Is it TIDAL or UAPP? The more information the better!