So I’ve listened to all the arguments from people who don’t understand the Nyquist theorem for why audio higher than 44khz doesn’t actually matter and you can’t hear it bla bla bla. From literal decades of personal experience of hearing the difference from the production side and knowing that from a physics perspective that it’s just not true, I present objective evidence that you can hear frequencies above 20khz.
First: a sample of a track I’m currently mixing/mastering
https://drive.google.com/file/d/1WvSAkDAlV4g0joqmlgJcVSDKrLBq3bkO/view?usp=sharing
Second: the same exact sample at the same exact volume with a 22khz tone applied.
https://drive.google.com/file/d/1LK6n5zd6QsrzcfW9n967NPsAzp2BRaA8/view?usp=sharing
If you can hear the difference (spoiler alert: you can), then you objectively can hear frequencies above 20hkz and by extension you must necessarily concede that there is a point to having waveforms capable of representing higher frequencies.
When frequencies mix in a nonlinear system, sum and difference frequencies are created. When supersonic frequencies are involved, the difference frequencies can dip down well into the audible range, and because they are not harmonically related to the actual musical signal, they sound awful.
In a theoretically perfect system, you could have ultra wide bandwidth recordings without this problem. While few people can actually hear anything above 20KHz (By the time we reach adulthood, most people can only hear sounds up to 15-17 kHZ.), at least there would be no intermodulation distortion products to degrade the music below 20KHz.
I feel like we’re saying the same thing with different words