i like it. and last time I checked; Tyll didn't have his measurement equipment completely setup. http://www.innerfidelity.com/images/AllAmpGraphs.pdf
looking at the graphs some are obviously weird. like the alo audio phase response.
The FR curve goes way beyond what you can hear. normals like 20-20k. The FR goes to like 100k or something. Not gonna hear anything close to that.
"Some of the amps measured very well (like the Pico and O2) and some did not. The problem is figuring out if an amp was measuring poorly because it's just poorly designed, or because of some problem with my test equipment or procedure. Sadly, I think there's a bit of both going on. Let's step through some of the amps in the .pdf (Headphone Amps .PDF here), I'll explain some things about the measurement interpretation as we go along." - Tyll
But something has to be extremely whacky in Tyll's measuring gear if the O2 was near perfect with NwAvGuy's measurements and it fails with other amps. Some of the measuring parameters were messed up in the first PDF.