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Grounding questions

I’ve had an issue with a slight hum through my system for a long time. System consists of Jolida Fusion Preamp and JD1000P amplifier. Both plugged into Futman Elite 15 power conditioner. It’s not dependent on any sources. Hum is there when amp is on. 
 

I have a dedicated line for the outlet to the Furman. Hum does not increase with higher volume. 
 

Maybe it’s an issue with the power amp but it could be an issue with the house wiring. The house is 62 years old and the fuse box is original and not grounded. Before I pay $800 to have it grounded, what do you think is causing the hum? It’s not cable related as I’ve swapped interconnects. The pre and amp are connected by a balanced cord. 

128x128mschott
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lowrider57's avatar
lowrider57
5,417 posts
 

@mschott

You’re fortunate to have @jea48 on your thread. I have one question, an electrician ran a dedicated line for you but left the service panel without a ground?

mschott's avatar
mschott OP
136 posts
 

There is no equipment ground. That is because I tried grounds and it made no difference.

The Furman does not have this indicator.

I don’t have an answer about the ground. I assume when they ran the new lines they just tapped into the existing fuse box. Aging a ground to that was not part of the contract. That is why I am now considering having a ground added.

 

yes I have a basic multimeter. 

builder3
770 posts
 

Your electrical system should be grounded, irrespective of audio issues.

I second the suggestion to take your amp elsewhere to see if the hum is still present. I'm inclined to think it will be, and that it's transformer noise. I have the same thing with mine.

erik_squires
16,394 posts
 

+1 on yes, it should be grounded. Will prevent shocks and improve surge protection. May not fix your hum.

At 63 years old, it is time to bite the bullet and come up to code my friend. In panel surge protectors, arc fault breakers and better distribution of your power circuits for the future, not to mention god only knows how many of those fuses are the wrong size.

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