Question Advice with ground hum


Well-known Member
Hi all,

Can someone advise me please on getting a ground isolator?

With certain items plugged into my receiver (notably my Sky HD and my blu ray player) there is a low hum (not massive but noticeable).

Also, my PC adds to this if I'm gaming on it.

I've purchased a ground isolator ( and placed the red end into the sub, then the sub cable into the other red end. This works well and stops the hum, however it does seem to reduce the bass I'm getting.

Any ideas?

With thanks,



Distinguished Member
Any ideas?

With thanks,

Hi, do you have it the wrong way round?

Does it matter which way round you connect it? This will dictate which leads I will need to buy to connect to my amp?
Yes, the signal level is reduced, the plug to ground should measure 70 ohms and is the input, the socket to ground should measure 40 ohms and is the output. Mine arrived with one of the channels crossed over and the replacement was the same, fortunately I had sufficient cable to fix the problem. Your amp inputs should be a sockets so plug the isolator into them and the isolator sockets should be your new inputs so you don't need any extra cables. Be assured you won't break anything.

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