Question Ground loop issues...but need some help

Facefirst

Standard Member
Hi all,

Firstly, a big hello to you. This is my first post. Secondly, I did search and search (promise) but cannot fully understand what issue I am having even though it seems similar to several others. I can't quite figure out what is going on, and hoped that some of you clever people might offer some guidance.

The short story is that I have just purchased a Gold Note PH-10 phono stage and it hums like a [email protected]@rd. My little Pro-Ject S2 phono stage - on the same power outlet and using the same cables - doesn't. I have tried the following. as per the suggestions in other threads:

Checked connections from the cart through to the amplifier: all good, and putting the TT through the Pro-Ject PS causes no issues.
Unplugging everything around the new Phono Stage, and just running the RCA from there to the amp: Still hums,
Tearing down the whole system, leaving just the speakers plugging into the amp, and the phono stage into the amp, all via the same power supply: Still hums.
Moving stuff round the room: Still hums.

The ONLY thing that seems to stop the humming is bridging the ground pin / screw on the PS to one of the outer (cold) RCA pins. Then, instant silence.

Which leaves the question: is the unit faulty, or is there some other thing I need to try? There is no option to run a ground from the PS to the chassis of the amp per se; I'd have to bodge that as the amp (Naim Uniti Nova) does not have a ground pin. Just to reiterate; I do not have the same problem on my other PS at all, just the new one.

I want to make 100% sure I have tried everything before sending the unit back.

So, so much thanks in advance!
 

Facefirst

Standard Member
Errrr....so it turns out that my amp has an earthing switch, and you can toggle between grounded and floating and mine was...you get the picture.

I'm such an idiot...
 

Facefirst

Standard Member
Thank you. I was dreading having to send it back or worse, having a really serious issue with the room or something that I'd never quite fix.
 

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