This page tests a browser's support for different wav file codecs and sampling rates. All the sound files on this page are based on a public domain "evil laugh" sound bite that I found at http://simplythebest.net/sounds/WAV/sound_effects_WAV/people_wavs_2.html
It's about 7 seconds long, and the file sizes are given in case you want to compare.

8000 Hz 11025 Hz 22050 Hz 44100 Hz
Mono Stereo Mono Stereo Mono Stereo Mono Stereo
PCM (uncompressed) 8 bit wav (53 KB) wav (105 KB) wav (73 KB) wav (145 KB) wav (145 KB) wav (289 KB) wav (289 KB) wav (577 KB)
PCM (uncompressed) 16 bit wav (105 KB) wav (210 KB) wav (145 KB) wav (289 KB) wav (289 KB) wav (577 KB) wav (577 KB) wav (1,153 KB)
PCM (uncompressed) 24 bit wav (157 KB) wav (314 KB) wav (217 KB) wav (433 KB) wav (433 KB) wav (865 KB) wav (865 KB) wav (1,729 KB)
PCM (uncompressed) 32 bit wav (210 KB) wav (419 KB) wav (289 KB) wav (577 KB) wav (577 KB) wav (1,153 KB) wav (1,153 KB) wav (2,305 KB)
u-Law compression (really 'mu'-Law) wav (53 KB) wav (105 KB) wav (73 KB) wav (145 KB) wav (145 KB) wav (289 KB) wav (289 KB) wav (577 KB)
a-Law compression wav (53 KB) wav (105 KB) wav (73 KB) wav (145 KB) wav (145 KB) wav (289 KB) wav (289 KB) wav (577 KB)
IEEE Single (32-bit floating point) wav (210 KB) wav (419 KB) wav (289 KB) wav (577 KB) wav (577 KB) wav (1,153 KB) wav (1,153 KB) wav (2,305 KB)
IEEE Double (64-bit floating point) wav (419 KB) wav (836 KB) wav (577 KB) wav (1,153 KB) wav (1,153 KB) wav (2,305 KB) wav (2,305 KB) wav (4,609 KB)
IMA ADPCM (4 bit) wav (27 KB) wav (53 KB) wav (37 KB) wav (73 KB) wav (73 KB) wav (145 KB) wav (145 KB) wav (289 KB)
MS ADPCM (4 bit) wav (27 KB) wav (53 KB) wav (37 KB) wav (73 KB) wav (73 KB) wav (145 KB) wav (145 KB) wav (289 KB)
MPEG Layer 3 (set to lowest bandwidth requirement) wav (8 KB) wav (17 KB) wav (7 KB) wav (16 KB) wav (20 KB) wav (33 KB) n/a n/a