Hum in my system; its the turntable R and L interconnects. Huh?

buellrider97 and ditusa, Thanks for your suggestions. I read the article and several others by PS.

1. The hum is created by the TT R and L interconnects even if the TT is not plugged it. If fact plugging it in or out makes no change.

2. I tried using a 2 prong; no change

3. I plugged everything into a HT Monster Power HTS2000 power strip I had on hand; no change. I tried eliminating the ground prong on the power strip, no change. The only thing that works is disconnecting the R & L signal lines from the TT. 

I can only guess that it is a fault inside the TT wiring.

Good tips! I'll try the additional ground wire, dbl check the cartridge clips are tight (pretty sure they are, they were a tight fit going on). The TT cables picking up EM is a suspect as even when the TT is disconnected from power, the hum is there. I am also going to try a different TT later this week.

All good suggestions! The cables from the TT are soldered in place, they can't be swapped. I would consider upgrading the cables if when I try my son's TT in the system, the hum goes away,

I did try different cables between the EAR and the amp: no change. And tried a different input on the amp: no change.

Update: I took the EAR over to my friends house and tried it in his system. The EAR was quiet. So it's for sure originating in the TT. Odd that the TT will generate this feedback even if its not plugged in. So its not being generated by energy in the TT, it must be related to a internal wiring fault or the picking up of interference. He has an oscilloscope and has offered to hook it up to the TT to look at the sine wave. I'm not an electrical engineer so not sure what I can learn from that. 

I also ran a ground wire from the EAR to the amp: no change. 

I have not tried the TT in another system, or a different TT in my system. More to follow. Thanks to all of you that have shared your expertise. It's a journey... 

Thank you.

I did that and it did not correct the issue.

My experienced audio friend took one listen to the system and said its interference being picked up by the TT R & L cables. BTW: the interference is there even if the TT is not plugged in. 

I have for sure narrowed it down to the TT as the source. 

Well it wouldn't be an aesthetic fix, but I could run a test wire from the tonearm base plate to the EAR based on your suggestion. Then if that corrects the problem I could flip the table over and make up a connection from the underside. 

Thanks so much for the suggestion!

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