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Comment by hasmanean | Hacker News Reader

Yeah nobody hears 16khz sine waves. But those high frequencies also make low frequency transients (eg square edges)sharper, and reduce ringing.

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But if someone can't hear a high enough sine wave, doesn't that mean the same thing as they can't perceive the sharpness of transients with frequency components above their hearing limit? Surely if you can't hear a frequency when presented as a high-intensity constant sine wave, you're not going to hear it when mixed in with all the other frequencies for a short moment in the form of a step or impulse. Those hairs in the inner ear aren't going to activate, in other words (or their signal won't get through).

I am not an expert on this but my suspicion is that human ear is not a linear time invariant system and thus it does not make sense to place a hard cutoff at some frequency over which you can not hear. The response might change wrt to the spectral content of the overall sound.

I can pretty distinctly hear 18kHz sine waves and so can many of my friends, I don't think it's that rare.

If you actually weren't able to hear past 16kHz you wouldn't be able to hear the ringing caused by a good filter above 16kHz, and you wouldn't be able to tell a difference in the transients either.

Defffffffinitely did not just hurt my ears playing really loud 16,220 Hz sine waves to prove someone on the Internet wrong.

I got up to 21kHz and then either I stopped being able to hear things or my speakers crapped out, not sure. On an unrelated note, those frequencies are annoying

Fun fact: most "maximum frequency humans can hear" numbers are not actually "maximum frequency humans can hear" but rather where the threshold of hearing (minimum volume level you can hear) crosses the threshold of pain (minimum volume level that is painful).

When I started my career I could hear 15,625hz (the line rate of the CRTs in a PAL environment). I can't now, and not just because those CRTs no longer exist.

Alas I can still hear 1khz.

I can hear 16khz sine waves when played on their own. ¯\_(ツ)_/¯

That's nice, try to conserve it and be careful with your ears. Most adults have already lost enough of their hearing that they can't even hear if an old style CRT based TV is on (which is in the EU 15625 Hz). By the ripe old age of 50 you're lucky to get 10 KHz and when you are at 70 it will be much less than that still. Babies and dogs can hear ridiculously good. The highest note on a piano is still below 5 KHz.

Handy resource:

https://www.szynalski.com/tone-generator/

Note that higher frequencies are very directional and you may have to move your head around a bit to catch the tone, this works best by finding something you just can't hear and then to move your head around to see if you really can't hear it or if you only can't hear it from that particular direction.

I'm 53 and I can still hear the NTSC 15.734KHz whine of a CRT, although it's not nearly as obvious as it was in my 20s. I also suspect there are some "dead" spots in my hearing in the 13Khz-15Khz range but it picks back up from there for a bit.

You're very lucky! In my early 40's I could still hear it but now I really can't, the cutoff is below 10 KHz already. But tinnitus doesn't help, it tends to reduce your hearing sensitivity overall.

I've got a strong tinnitus, but I still hear up to about 14Khz (I'm 53). In fact the tinnitus is all those frequencies up to 21Khz I used to hear and don't anymore, ringing in full in my ears...

Tinnitus is a collection of different symptoms, you can have various forms of it, for instance where you hear a continuous ringing in the background, where certain frequencies get dampened or amplified and so on. It's quite an interesting phenomenon. 14Khz at 53 is very nice!

Also I know that my medication plays a role in my tinnitus -- I switched for a while, and my tinnitus went down notably; unfortunately with the other medication I had tachycardia, which is worse than tinnitus...

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