So, basically just upload to Open Source Audio?
Yup.
Only catch for me: at least one of the comps is a studio track played back over my home stereo. I imagine there're legal issues with upping that one. But the others...cool!
Yes, it's probably better if the files are just a small (~ 1 minute) sample size rather than a full copyrighted song. In regards to Matt's AKG comp, the band is no longer together so I'm guessing that would be a little closer to ok than say posting a Bob Dylan track.
For future consideration, I imagine that samples of classical would be a good choice when doing comparisons for rights and sonic reasons.
If we get a bunch of them in there I'll try to create a collection for them so you can hit a homepage with a URL like this and browse/find all of them easily (not active yet)
http://www.archive.org/details/GearComparisons