Page 1 of Subwoofer hum

I`ve recently had to reinstall my home cinema gear but have noticed that the sub (Tannoy) now makes a distinct audible hum when in use. It this normal?

It could be a mains hum, its caused by the cables/sub amplifier picking up the sine signal from the electrical wiring in your house.

You usualy get it from running speaker/phono leads to close to an extension lead or sockets or when the outer screening part of phono cables isn`t connected properly or using those cheap black throw away type cables.

Try swapping some cables around or moving the sub away from the wallas a ring main cable may pass behind it under the plaster.

My Pioneer sub does this and it drives me mad I`ve had a replacement and it`s exactly the same. Reading a manual for the rel subs they reckon it`s to do with the way the sub is earthed.

Also, make sure that any cables that run across each other cross at right angles...........Think cross +.

Are you sure its not a poor quality connecting lead...maybe with bad grounding? switch cables. Just a thought :-)

My REL does this too, even when it`s not connected to a source. I have to turn it off when not in use because it drives us mad.

Well it`s good to know I`m not the only one experiencing this problem. I`ll try moving the sub away from other power sources and cables and see does it make a difference. Thanks.

Try moving the plugs around - I had an awful mains hum from my last sub. Cured by plugging all the amps into the same 4-gang extension.

Dan what REL do you have? most of the Q range have an earth switch that you can use if your sub has a hum on it.

It`s the Q50 ?

I`m having an rel quake delivered today I`m praying there`s no hum on it! I`ve got a sneaky suspicion it`s my mains that`s causing the hum on my current sub.