CH> I can get the center channel (mono only) and stereo (left-right) to work
 CH> but getting the rear speakers is harder.
 CH> You wrote to make just the rear speakers sound:
 CH>   3) Get a RCA wire and split the wires, and reverse the two wires
 CH>   inside. Making the ends reverse polarity.
 CH> Well, what do you mean? I took an RCA wire apart and only saw one
 CH> wire. How can you switch them?
Since you are asking in the PRO audio area, obviously you shitcan the cheap 
consumer crap some jerk snuck in and replace it with pro gear.  That will 
allow you to simply reverse the + and - side of your balanced/differential 
line as desired, or bridge the L or R with reversed polarity.  
 CH> also, are there any standalone products or computer programs that
 CH> will take a sound/input and "reverse its polarity"? It seems simple
It shouldn't be too hard on some DAW software.  With unbalanced lines, you 
have to use either an opamp inverter or a transformer.  The latter, being 
passive, is very simple to connect.  You need to learn about impedances, 
loading, and that good audio transformers typically cost $100-200 each (per 
channel).  Any electronics supplier, including Radio Shack, can supply 
relatively decent opamps, such as LF-353, TL-070 and 80 series, etc.  
Some shoddily designed electronics even reverses polarity when it shouldn't.  
Terry
--- Maximus 2.01wb
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