Uploading music...?!

Uploading music...?

Hi, I would like to upload music samples (from commercial music) onto my website to compare different audio formats.

I heard some people say uploading songs of any length is illegal, while others say you can upload up to 30 seconds...

What is the legal length that I can upload a commercial song?

I've tried researching google, even went on the RIAA website, but theres no hard facts on samples.

PS: The songs would be in ~16Kbit (very low quality)

Thanks.

Here's a wiki article that might help.
:)