its hard to cancel off the vocals if the tracks are oreadi mixed down..i understand there are softwares and hardware that could do it..the truth is no software or hardware can remove the vocal track completely without affecting the frequency of other tracks in a song.
bcoz most songs the bass drums and vocals are set/panned in the center or somewhere in the center..not only the bass drums, sometimes other instruments too are set in the centre along with the voice...
so the end result would be unpredictable..sometimes it really does not work coz u will hear weird sounds after cancelling the voice...sometimes it works fairly well but still u can hear the voice drowning in the song. sometimes it cancel the voice completely along with other tracks that are close to the vocals... and sometimes if can cancel JUZ the vocal alone without affecting other sounds but rarely happens....it depends on how the original was recorded.
but nevertheless im still using vocal remover plug-in, AnalogX, for certain songs..u can try it too..it can plug to any software including Adobe Audition..