Help! New Nagaoka MP 500 Cart Makes Hum Ground Noise


I have the new Nagaoka Mp 500 cart installed on my Techniques 1200G turntable connected to my Luxman 595 amp. When I turn the volume up, I hear a hum in the speakers. If I remove the cart from the arm, the hum goes away so I know it's the cart. It's with the original Techniqs head shell. I didn't have the issue with the Oltofon 2m Black LVM cart. 

Aside from that, I like the MP 500 a lot. Sounds good. But I am freaking out... not sure what to do about the hum grounding noise?!?

On my luxman, I have both the turntable and the REL sub on the ground in the photo. 

Here are the photos on imgur https://imgur.com/a/yEwvvAq

dman777

I posted this in your headshell thread....

Not sure what caused it, but on on my SL 1200gr with the MP-500 there was a hum issue with every metal headshell that I tried (including the stock one). I tried a wooden headshell (bought on Amazon) and that solved it. Probably could have been solved with non-metallic screws instead.

I should add that none of my other cartridges have the hum on the same turntable.

Try another pair of ICs to TT. Also double check wiring of cartridge to headshell, especially green and blue. Make sure they’re correct and tight to pins.

I am at work on my mobile, so just doing it quick reply... The ortofon cart also has a hum but not nearly as bad as the mp 500. I didn’t think to look to notice it until I start investigating with the MP500 ane comparing. So, even though the ortofon isn’t nearly as bad it stinks I do not have a black background. I went the extra mile and even had electrician run two dedicated lines to the circuit breaker about 2 years ago.

We were setting up a new SL1200 mk7 and we had a serious hum - it was the headshell not the cartridge. Surprise!