@nullc: of course you're right, and the commenter you're replying to does not understand the Nyquist-Shannon sampling theorem. Which is a shame, because the article specifically addressed this point.
These discussions of audio standards always get sidetracked by people who don't understand or believe this result. (Have to admit, the result is surprising).
I think there may be problems with the argument in TFA, which is based exclusively on standard linear systems theory.
Of course, the ear and some of its perceptual components may be significantly nonlinear, and thus not covered by the frequency response graphs of TFA.
These graphs assume linear systems, in which you put two frequencies in, and the same frequencies pop out in scaled form. Nonlinear systems can produce new frequencies in response, and this possibility is not discussed in TFA. Probably these effects are quite minor, but may be audible to some listeners on some equipment for some choices of source material.
Indeed, but if there were non-linearies in the ear (there are many, of course) which allowed detection of ultrasonics (less likely, because the first stage of the ear is impressively linear) you'd expect them to show up in the actual listening tests.
The TFA does at least make this the-proof-is-in-the-pudding point somewhere in its depths. :)
These discussions of audio standards always get sidetracked by people who don't understand or believe this result. (Have to admit, the result is surprising).
I think there may be problems with the argument in TFA, which is based exclusively on standard linear systems theory.
Of course, the ear and some of its perceptual components may be significantly nonlinear, and thus not covered by the frequency response graphs of TFA.
These graphs assume linear systems, in which you put two frequencies in, and the same frequencies pop out in scaled form. Nonlinear systems can produce new frequencies in response, and this possibility is not discussed in TFA. Probably these effects are quite minor, but may be audible to some listeners on some equipment for some choices of source material.