[musesum]

well, I used to have super hearing. Had a hard time being around CRT displays because the flyback transformers were really really loud. Now, with age, I get a phantom limb tone of 16KHz. [1]

Coincidentally, the peak notch in the OP was the 1st subharmonic of that.

[1] https://en.wikipedia.org/wiki/Flyback_transformer

[eps]

This is very common though, isn't it? Every child can hear a tube TV running when muted. Dog whistles too and all. And that's not even at the top of kids hearing range.

[copperx]

Yes, that's normal hearing for a child.

[TT-392]

Does not being able to be around CRT displays because of the noise make qualify one as having super hearing? Pretty sure a good percentage of the population have that problem

[musesum]

Was tested while attending an electronic music class. Professor displayed everyone's result, so we could compare. His chart was the worst, as a cautionary tale. Too many live performance in front of the PA.