[78-L] stylus for vertical-cut Edisons

[David Breneman]

--- On Tue, 3/15/11, Mark Bardenwerper <citrogsa at charter.net> wrote:

> In other words, reverse polarity on only one side?

Yes!  One channel of a stereo cartridge is already wired
out of phase.  This is so it will play a (lateral) monaural
groove and send the signal to both channels IN phase.  By 
swapping the polarity of one channel (either one) it
sends the signal from a vertically modulated groove in
phase to both channels.