Yaron Kaplan said the following to All on the subject of
Filtering songs (29 Oct 97  17:34:44)
 YK> I personally greet you, All.
 YK> Is there a program or a device that can filter out the musical
 YK> instruments from a song and leave only the human voices ?  I asked that
 YK> question in another mail net, but they didn't reply.
 YK> Bye,
 YK> Yaron Kaplan, Israel.
The usual device one finds is called a vocal zapper. This removes the
vocals and leaves the instruments. I think if one were to invert the
phase of the vocal zapper output signal and add it to the original then
this should in theory cancel the instruments.
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