Scott, welcome and let me point out that "the power supply of the subwoofer amplifier does all the 'conditioning' required of the incoming AC signal".

Okay, now that I've performed my basic function, I'll expand the comment. Amplifiers don't use the power that comes out of the wall socket. The transformer, rectifier and filter capacitors in the power supply section of the amplifier "condition" the AC which may be more or less "dirty" into clean DC for the output transistors to add to the incoming voltage signal to make it about 25-30 times stronger so that it can drive a speaker at a usable volume level. The result is that when these amplifiers/receivers are tested, the noise level is inaudibly low, regardless of the condition of the power coming out of the wall.

One of Monster's scams used to be(don't know if they still run it)that the salesman would plug the Monster noise analyser directly into the wall socket in front of the sucker(er, customer)and then smile while it vigorously hummed and howled. Then it was instead plugged into the Monster "conditioner" which was plugged into the same wall socket, and of course it was now quiet as a lamb.

Standard cords of 18ga(as Philippe mentioned)or thicker have plenty of capacity for the needs of audio equipment(a hair dryer is a tougher task), so use what you have or buy another for a few dollars.


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Enjoy the music, not the equipment.