it's practically impossible to do what you want to do with just mp3s. the closest thing i can recommend only works with vocals and only works if you have lossless quality rips and the original and instrumental versions of the track to produce a vocal track. Google "Utagoe". It's Japanese and so is the interface but there was a tutorial up a while back and I can't remember the site that did it.

As for specific instruments, it'd probably be easier to learn how to play it by ear and remake it.

np! I've been messing around with mashups and remixes for a bit on the side though i haven't really made anything epic yet. hope you have more luck than I've been given XD

(This post was last modified: 29/02/2008 04:52 PM by Method.)

As for vocal removing, most tools will do a "channel mix" removing "central" material, which usually also makes the song sound funny.  You can try removing some tracks by filtering out frequency ranges (if, for example, the particular track is always a high frequency), but it generally doesn't remove all traces of it.

As said, it's best if you have the original in elementary track form.