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Ground Loop Hum

Hello, I am looking for help eliminating the hum I get in my subwoofer. I have a Rel B1 and am using the high level inputs. The Amp I am connecting it to is a BAT VK-600. Based on the documetation this should be treated as dual mono blocks so I have the two hot wire connected and the ground going to my pre-amp ground. I have tried different grounds including the one on the power conditioner. I have tried all the normal tricks of moving where the cable runs, unpluging all other componets, etc.

Any thoughts would be appreciated.
mabrooks51
xti16
1,525 posts
 
Is the REL plugged into the power conditioner or the wall? If the wall the conditioner may be isolating the ground causing the hum. I had a hum from my cd player and lifting the ground fixed it.
mabrooks51 OP
3 posts
 
Thank you for your feedback, I will go to Radio Shack and get the isolator. The Rel is in one power conditioner and the BAT is in a different one designed for high current. When I ground to the BAT chasis, the hum is much less then when I use the pre-amp chasis ground so there is some interaction even when nothing is hooked up.
shadorne's avatar
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shadorne
7,477 posts
 
You could also consider a Jensen transformer between the preamp and amp ( I don't like to add transformers because they distort but it is an option that may work for you - Jensen are high end transformers). I hope you are using only XLR connectors? If you use RCA then hum is not uncommon. A trick with RCA is to use an unshielded twisted pair - as ground loops are usually picked up on a shield.
cyclonicman
693 posts
 
Hi, don't know if this will help, but I had a similar problem with my subwoofer until I changed my analog interconnects from my power amp to the subwoofer. Once I removed the Nordost SPM interconnects to the subwoofer and replaced them with Audioquest SubX subwoofer interconnects
my subwoofer was completely silent.
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