On a sunny day (Fri, 23 Feb 2007 21:41:59 -0500) it happened "John Gilmer"
wrote in :


There is a little catch here.
The PC case is normally connected to mains ground, and we want the quality
of the line between zero and phase, then without a transformer we also
grab
all the noise and stuff between ground and zero.
That could show some peaks in some cases..

True.

If your sound card can record stereo, you can make channel 1, "Neutral" and
channel 2, "Hot."

Exactly, do a differential.
So then split the tracks, and substract with my substract wave program (Linux):
http://panteltje.com/panteltje/dvd/s...t_wave-0.3.tgz
reload the result in a good sound editor, do a FFT.. what not.
One could even listen to it ;-)