OP’s buzz sound
https://drive.google.com/file/d/0B_YygM_VDhV9RWlPMEVudjBnb28/view
60Hz hum/buzz sound
https://www.youtube.com/watch?v=E_Sf7rSOU78
The OP’s buzz does not sound like a 60Hz hum sound to me.
naseltzer OP
2 posts 10-03-2017 10:22pm
Okay, I took the sub to the other end of the house. I still heard a buzz, but I *think* it may have sounded a bit more faint. I’ve also tried connecting only one amp to one speaker, directly to the wall with everything else unplugged. No change. I also tried a cheater plug on an amp. Didn’t help!
@naseltzer,
Everything else unplugged? As in all the 120V AC power equipment plugs unplugged from the AC mains power? Especially the plasma TV? Some plasma TVs are notorious for spewing harmonics back out on the AC mains. Other items that spew harmonics back on the mains, as well as radiate in the air are, light dimmers, CFL lights, LED lights, electronic light ballasts, and cheap switch mode power supplies.
A few years ago I read a thread on another forum where a guy was having a buzzing sound problem and he tried everything he could think of. It ended up being caused by old refrigerator he was using in the garage.
Your buzzing sound sounds likes a higher frequency sound to me. But not quite like 120Hz.
https://www.youtube.com/watch?v=pC4Uzt0qm2E
I thought at first it might be a bad electrolytic cap in the power supply in the power amp. But you have two separate mono amps with their own power supplies. What are the chances both could have a bad cap?
As for the test with the sub taking it to another room and checking for the buzz. I think you need to short out the input on the sub for a more accurate test. With the input open ended it will pick up surrounding RFI anywhere near the input. If the sub has a single ended RCA input you can use an RCA interconnect and stuff some tinfoil in one end to short the center pin to the outer shell of the RCA plug. Plug the other end of the interconnect into the RCA jack on the sub. For 120V AC power use a receptacle outlet above a counter top in the kitchen. These are 20 amp circuit receptacle outlets and as a rule there are not that many receptacle outlets on the same of 2 minimum code required kitchen circuits.
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