High-pitched frequencies

xthread posted these .mp3s, along with a description of what they are. I am extremely curious as to how many of you can hear them. Both are direct downloads, not links.

The first sound.
The second sound.

[Poll #740436]

xthread's post is here.

EDIT: Eight people have responded so far. The answers are of very mixed ages for the first sound, but almost perfectly divided age-wise as predicted for the second (apart from one teenager that can't hear it). Fascinating.

EDIT RELOADED: Now the teen who couldn't hear the second one changed her answer. And another teen can hear it, and two more adults can't.