If you are using Windows, there’s an excellent tool that’s included with Sound Forge Audio Studio: Izotope Vocal Erasure. It works to remove vocals OR extract vocals. It has several controls to finesse the results. I was very pleasantly surprised at what good job it does to extract vocals for acapellas. Of course, the results will vary greatly depending on the source material. Whatever degree the non-vocal frequencies overlap with the vocals can obviously not be completely eliminated, though they are usually greatly attenuated.
Sound Forge Audio Studio is also relatively inexpensive (list 59.95 but Sony has it for sale @ 44.95: http://www.sonycreativesoftware.com/audiostudio). It’s a very good general purpose audio editor and the stepped-down version of Sound Forge Pro, which has been is one of the best audio editors available. I’ve been using Sound Forge Pro for over 15 years – so I guess that sums up my personal opinion ;-). Note that Vocal Erasure is NOT included in the Sound Forge Pro, it’s only on in the Sound Forge Audio version. However, if you look around you can find the standalone installation version of Vocal Erasure, it will work with Sound Forge Pro. Sony has also released the first Mac version of Sound Forge Pro but AFAIK, it does not include Vocal Erasure.
There are other vocal extraction/removal utilities but this is the best that I’ve found. I’d love to hear from folks who have had sucdess with others.
Hope this helps.
.
