this got me to wanting to test out my speakers and hearing...
so i came up with my own test.

it goes for 4Hz to 24kHz and it's a wave file, not mp3.

www.patrickdsp.com/audio/4Hz-24kHz.wav

it's not a steady stream, i kicked up a few notches where normal hearing lays. other wise this wave file would be way too long to share.

cheers