[genewitch]

Oh come on. I have handheld recorders that do 192khz.

"Headroom"

And the idea that humans can't hear over 20khz is like "humans taste 'sweet' on the tip of the tongue, and 'bitter' on the sides"

As we get older the hairs in out ears break or whatever and our perception decreases, but I could hear the fly backs in my old monitors, I used to be able to see the flicker in 3khz pwm LEDs, and my induction hob drives my kids crazy but it's merely midly annoying to me.

Get a real soundcard and some young people and play square(pwm) and sine tones starting at 16khz and find out where they can't hear it anymore. I find studio monitors with tweeters that are not paper are the best.

[Sesse__]

If you think you can hear ultrasound, it's nearly always due to nonlinearities in your system producing non-ultrasound when you try to play it. Seriously. (You can sometimes hear above-20 if it's very loud and/or you are pressing the source against your skull. Above-40 would be completely insane.)

The extra headroom can indeed be useful for some kinds of processing, but you can safely discard it for actual listening.