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Why is a 1.5-2 volt AC signal on my Neutral line?

I have several music sources e.g. DVD, Phono, DAC, Tuner etc...

I just purchased a NAIM integrated amp and I am experiencing a hum but only from the DVD player.

I have circuit tested the entire house wiring and all is well.

After a lot of investigation I found that some units have a 1.5-2.0 volt AC signal (sounds like a 60Hz signal i.e. hum) between the neutral side of the interconnect and the earth at the power bar.

Panasonic, Pioneer and Sony units I have measured all have this signal present and it varies between 1.5 - 2.0 volts

Luxman and Cambridge Audio gear does NOT have the signal present

All units have a polarized plug with no ground pin

How can the hum be eliminated using the Pioneer DVD with the NAIM Amp?

Thanks
williewonka
jea48
4,538 posts
 
After a lot of investigation I found that some units have a 1.5-2.0 volt AC signal (sounds like a 60Hz signal i.e. hum) between the neutral side of the interconnect and the earth at the power bar.
Williewonka 06-24-10:
between the neutral side of the interconnect and the earth at the power bar.
Williewonka,

Not sure what test you preformed.... Can you be more specific. What do you mean by "neutral side of the interconnect"?

Lifting the ground makes the amp hum more
06-25-10: Williewonka
Are you sure the sound you are hearing is a hum and not a buzz. Does the noise vary when changing the volume level?

I just purchased a NAIM integrated amp and I am experiencing a hum but only from the DVD player.
06-24-10: Williewonka
I would try what Al said in his post. Could be a bad interconnect. Could be a bad signal ground solder connection inside the DVD player.
Does the hum/buzz change if you put your hand on the metal case of the DVD player?

I would also try another set of line-input jacks on the NAIM.
Post removed 
simply_q
124 posts
 

Blindjim

Water your service ground.

Service ground has absolutely no relevance at all.
blindjim
3,092 posts
 
Simply_q

it'll sure tell you if there is a weak connection there.

it's certain there's a weak connection, or resistive connection somewhere , if not in one of the devices, then it has to be in the service.

I'm figuring the house is older than the equipment and felt to start from the begining ... at the service pole and follow it back to the outlets being used. Skipping around looking at this or that seldom plays out well.

I've seen far wierder stuff happen.
simply_q
124 posts
 

Blindjim

it'll sure tell you if there is a weak connection there.

No it won't. The ground road has nothing to do with your audio system or with any ground loop noise in your audio system.
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