Can I use a polarity checker, kind they sell in Home Depot, to accomplish the same, unless you meant to do this test for a purpose, other, than to check polarity of each receptacle?No, you will not be checking if the receptacle polarity is correct.
I cannot understand one thing, though- how come the hum is louder in one channel???
You will be checking if the 120V AC polarity orientation of the primary of the power transformer of the power amps is correct.
If you do not have a multimeter you might just try a simple listening test. Same set up with the ground cheater just listen for any difference..... The meter is the best sure way though.
You can pick up a decent one at Rat Shack for around 50 bucks....
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