2. tech-talk
  3. 180236-91472

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
gs5556
1,239 posts
 

First things first: Power on the amplifier without the preamp. If the hum goes away then connect the preamp. If still no hum connect the source components one at a time to the preamp until there's humming. Then we can narrow it down.

Post removed 
mschott's avatar
mschott OP
136 posts
 

Thank you. I don’t remember if I used a cheater prior to the dedicated outlets which by the way are not GFCI. I isolated the power amp and there is hum from both speakers. When I plug it directly into the wall, there is hum from both speakers but the frequency seems a little different. 

Post removed 
mschott's avatar
mschott OP
136 posts
 

Then I did use a cheater. Yes the outlet is same as the Amazon link in your last post. 

More to discover