Humming noise created by the turntable platter

[mudhead77]

My project debut 2 has some irritating hum sound through left channel. In fact, after a week of digging, i discovered the noise is created from the metal turntable platter. If I touched the platter, humming noise was getting weaker. I am not sure it is related to grounding issues or it is the statics created by the platter, spinning for years and the platter turned up to be a magnetized metal. Once the needle played toward the mid of the record, the noise was getting louder. My turntable is an old version of UK plug (2 ways plug) and the phone stage is Onkyo with 100W japanese power plug (also 2 ways plug). The ground is connected to Onkyo grounding plug that I am not sure it does help grounding the statics and electric successfully.

Please advice how to fix the humming noise. Thanks.

[Bob_in_OKC]

The platter material wouldn't seem to be causing the hum just because touching it reduces the hum. If the hum increases as the cartridge moves closer to the center of the record, it is likely because an unshielded cartridge is moving closer to the unshielded motor.

[mudhead77]

Thanks for your reply.

I did change the cartridge to Ortofon 2M Red. I discovered the hum noise was created by the phone stage. I also use another phono stage, Disc saver, which is powered by 9v battery. I connected the output of left channel RCA with the earth wire, followed by the other forum in vinylengine. The noise has been reduced a lot, even there is still have some interference from the platter.

Pls suggest how to shield the wiring and prevent the increasing of humming noise in future.

[Bob_in_OKC]

You could perhaps upgrade your interconnects with shielded low-capacitance cable. But if you're still getting any of the hum that increases as the cartridge moves closer to the center of the record you may not be able to do anything about that. It's common with Grado cartridges on Pro-Ject turntables, but not Ortofon...as far as I know.

If you're getting anything from the platter itself, it might be motor vibration, in which case you might want to investigate that. It's a common problem with the Debut turntables, although my own Debut III hasn't had that problem.