There are a couple of money-based software products that claim to be able to separate instruments, but at best they only do an OK job, and they all require that you start out with a perfect stereo show. The piano, the oboe, and the violin can all hit that 'A' at the beginning of the concert. True, but they can all play similar notes, and that's what kills you for separating them. People keep trying to use the idea that some instruments have higher or lower pitch than others. If the vocal isn't in the middle, or has any of about a hundred other problems, it fails. Vocal Removal, when it works at all, works by 'knowing' what's in the exact left-right center of the stereo show. mp3 files - like i stated above - tend to have some artifacts and qualities that won't cancel out the instrumental near as well as.

Your ear can tell that the music is an oboe, but to the software, it's just a bunch of blue waves. flac files for the full song and the instrumental you're wishing to isolate (Note: make sure the bit rate is the same for both) Save yourself the headache and try to find lossless audio files.

How to separate instruments in a song