I hate snake oil as much as the next guy, but not everything in life (and music) is linear. Percussion instruments produce a highly non-linear sound wave (and i

I hate snake oil as much as the next guy, but not everything in life (and music) is linear. Percussion instruments produce a highly non-linear sound wave (and if you run it through a Fourier transform then you'll need all frequencies up to infinity to reconstruct the signal). We don't know how the human ear perceives percussive sounds and how the brain forms an impression of it (at least I've never read anything about it). Just because the ear doesn't hear linear, continuous frequencies above 20kHz does not mean it cannot perceive sudden, non-linear pressure changes at a much lower time-resolution. Admittedly this is a bit speculative, but you can't write it off without justification. Here is one reference on the non-linearity of the human ear: http://physicsworld.com/cws/article/news/2013/jan/31/human-hearing-is-highly-nonlinear http://physicsworld.com/cws/article/news/2013/jan/31/human-h...