Ground switch setting

Posted by: Dan.S on 11 December 2018

Quick questions for the community wisdom. I have a 272 with a PS connected to a 250DR. I know for a fact the wall socket I'm using is not grounded and also there's this annoying hum coming from the 250DR, so here it goes:

1. What setting should I use for the ground switch? Floating or chassis? Cant tell the difference myself, SQ wise.

2. Is there a way of grounding my system, for example using a clamp on the 272 chassis and connecting it through wire to the building radiator? Has anyone did this? What would the risk be?

Thanks in advance. 

Posted on: 11 December 2018 by trickydickie

You need to speak to an electrician, safety is the key issue here, resolve that and your hum will go away.

Posted on: 11 December 2018 by ChrisSU

Hum from a Naim amp or PSU is common, and changing the earth arrangement may make no difference at all. 

I will refrain from commenting on your mains earth (or lack of one) as the correct answer will probably depends on local safety regulations in your area. 

The 272 manual explains the correct position for the ground switch, and it will depend on what other sources, if any, are connected to it. If there is no effect on sound quality, it won’t matter which way it’s set, so you can also check this by ear. 

Posted on: 11 December 2018 by nbpf

On 1, please check https://forums.naimaudio.com/t...12#78019130872186712. On 2, you should probably ask an electrician. Best, nbpf

Posted on: 11 December 2018 by Japtimscarlet
ChrisSU posted:

Hum from a Naim amp or PSU is common, and changing the earth arrangement may make no difference at all. 

I will refrain from commenting on your mains earth (or lack of one) as the correct answer will probably depends on local safety regulations in your area. 

The 272 manual explains the correct position for the ground switch, and it will depend on what other sources, if any, are connected to it. If there is no effect on sound quality, it won’t matter which way it’s set, so you can also check this by ear. 

What he said....