It's even better now Kathleen, I don't know if you've seen the latest version. It used to merely mix the channels and remove anything which was the same in both (anything which would be in the centre, so vocals, but also other things) but the new version focuses on that and has a specific filter that targets the frequencies specificially (you can set these ranges) so you can make a karaoke type track, or do the opposite and make it accapella (though that rarely works well). If you try it on more recent music it works much better, perhaps due to different ways of mixing now I don't know. Try doing 'It's My Life' it sounds very good.