I don't know whether there is a standard answer somewhere on this forum to this standard question, but elsewhere the standard answer is as follows:-
" Is it possible to remove vocals from an existing track?
Well, the short answer is...Yes...and No. The simple reason for these opposite responses is that the process of 'vocal cutting' or 'vocal zapping' (as some say in radio) is a process that's been around for ages, known in many record engineering circles as "A minus B listening". Here's how it's done.
The tip: If you're using a track from the 60s, 70s or even early 80s, you've probably got a decent shot of removing vocals. Paul McCartney's "Maybe I'm Amazed" (1970), Astrud Gilberto's "Light My Fire" (1969), even Donald F.a.gen's "I.G.Y". and "Walk Between Raindrops" (1982) are four good examples to try out. But it's all to do with structure....
To do this in Adobe Audition's Edit View, simply highlight your file and go to Effect> Amplitude > Channel Mixer and select the VOCAL CUT preset. You can preview and toggle between NO MIXING and VOCAL CUT to hear what's happening. You can also alter the phase relationship between the L&R channels by dragging the sliders.
So what's happening?
1 - You're taking a stereo file
2 - Then inverting the phase of one channel
3 - Then add the two channels together
That's it - that's all you've done. Now what's the result?
1 - Anything that was centre stage (hopefully, in this case, the vocal) will be cancelled out.
2 - This includes the bass, kick drum and anything else that was also centre stage.
3 - Material which is close, but not, centre stage will also reduce in level.
4 - The end file will be mono.
5 - On most modern recordings, FX returns are stereo or pseudo-stereo. Thus all the FX returns on the vocal will still be heard.
The truth of the matter is that you can, perhaps, on some recordings, reduce the vocal level. Whether or not you can reduce it enough is only discovered by trying it out. You will still have to contend with the problems of other instruments which also vanish, the generally reduced bass level and the FX returns.
Now, because your resultant wave can sometimes suffer from center-channel dropouts of things like bass guitar and bass drum, here's something else that you can do 'after' you've run the vocal cut (ala, center-channel cut) preset on a file...
(this tip is easiest to achieve in multitrack, but could also be done with Mix Paste)
After using the Vocal Cut preset on your file, save it (with a new name) and hit Ctrl-M to insert the file into Multitrack.
Open the original file (pre-vocal cut) and run a low-pass filter on it so that ONLY frequencies below 200Hz pass thru (effectively cutting everything above 200Hz). This will leave you with a stereo waveform that has possibly 'some' vocal element, but will primarily carry the bass and bass frequencies.
Now, insert the 'low-pass' file into MT, aligning it with the vocal-cut version. Play with the volumes to achieve a proper balance. This will allow you to restore a bit of the stereo image (if needed) as well as improve some of the low-end response (if it suffered to begin with)...
You could also try a stereo simulator. This usually consists of adding a small delay and mixing this with one of the two mono outputs. The same delay signal is inverted and mixed with the other mono channel (so if the two channels are ever combined, you once again get compatible mono).
A full explanation the limitations of vocal reduction techniques can be found at
http://www.ethanwiner.com/novocals.html - this is essential reading!
If you really want more information, you can use a search engine like google to find thousands more pages of relevant information, including many software products and services such as (at the time of writing, 1992?)
http://www.yogen.com/ ($15 s/w product)
http://www.mtu.com/ ($54.95 s/w product)
http://www.pgmusic.com/ - "Copyscat" ($49 s/w product)
http://www.tracertek.com/dart_karaoke.htm ($39 s/w product)
http://www.vocalreduction.com/ (service. $19.95 per song)
http://www.csp-audio.com/vocalremoval.htm (service. Typically $45 per song)
http://www.analogx.com/contents/download/audio/vremover.htm (free DX plugin)
As for removing the instruments and keeping the vocals, this cannot be done - if you try to isolate the centre of the stereo image, where the vocal is usually found, you will still have any other sound that was in the centre, plus half of what was left or right of the centre. You can try this using (for instance) the Audition 'Channel Mixer', first applying the 'LR to Mid Side' preset to your file, then using the 'Both=Left' preset on the result.
Finally, if you want to use Audition just for removing vocals, that's up to you of course; but there is so much more it can do, and maybe so much more you can do - why not also try using it to produce your own original and creative work?"
--------------------------------------------------------
Having said all that (are you awake in the back?) it should be noted that Audition 1.5 rewrote the above rules by introducing a Centre Channel Extractor effect which can extract just the vocal from a file, or take it out leaving only the backing, while preserving the stereo image. You could try the trial download to see how well it works on the material you have in mind.
