From xxcaptinxx@comcast.net Fri Dec 30 09:37:24 2005
Subject:Re: unbalanced audio output on a C3/B3

Hypothetically, if you plug the mixer and the organ and the PA into the same
wall outlet, there should be no ground loop. The purpose of a ground lift
is to break the loop when something is miswired. You'd have to experiment
with your rig to see which alternative works best. The Hammond ground is
not zero-- rather it is "floating".

The purpose of a balanced line is to cancel RFI picked up by long cable
runs. As a practical matter, organ to 6W (147) style Leslies have been
unbalanced for years with no discernable bad effect, especially when excess
cable is not coiled. So I would first try the unbalanced jack into the
unbalanced input of your Mackie mixer and save the $$ if that sounds
acceptabe to you. This is particularly true if you are going to put the
mixer close to the organ anyway. The console tops out at about 6000 hz, so
high frequency passive DI concerns are mostly irrelevant or can be corrected
with EQ. A cheap passive Berhinger is probably enough, or you can buy an
1:1 audio isolation transformer for $6-8 and wire it in yourself. In my
opinion, most Hammond emulations are vastly improved by a -12db filter at
around 6000 hz anyway.

The signal will be a little hot, but nothing the Mackie can't handle. You
can bleed some signal to ground in the balanced line alternative just like
the schematic for the unbalanced out does. The Hammond is basically lo-fi,
so the improvements sought for guitar and voice have little utility in our
application.

I don't know what your ultimate intention is, but a lot of the Hammond vibe
is in the interaction of the sound through a Leslie. DI mixed with
well-placed mics is terrific. DI alone is somewhat sterile. YMMV.

Regards,

Dave Bishop