You need to combine a number of tools to achieve this. It will probably not be possible to completely serperate the vocal. I use MAGIX Audio Restoration which I use for general audio restoration -cleaning-lab/. I often use its tools to widen the stereo image, seperate the centre and side channels even further. I then use bx_solo(free) -music.de/en/download?PHPSESSID=aeogopu3v7kbu0e0efe495u... or some other tool to ms decode the sound (seperate the mid channel from the stereo). Not a perfect solution.