Eliminating subwoofer hum/buzz

[kropaske]

Got myself a home theater kit the other day but my sub makes humming/buzzing noise when powered on. I guess it's the noise from AC network. So for testing I plug it in to the shaver socket as it's separated transformer and most of the noise is gone.
So i need to connect it through isolation transformer of some sort. I would like to keep it as small as possible and sub is only 100w.
Any suggestions?

 

[The Ghost]

Earth the system?

 

[kropaske]

Will it make a difference? It's a class 2 equipment and casing is not connected to any internals I guess?

 

[Midwest]

Ask these bods, we only know how to install the sockets

Home Cinema Speakers - https://www.avforums.com/forums/home-cinema-speakers.45/

 

[static zap]

Wave your magic "Volt stick / fairy wand near the cases"...
1x earth may help -near an amp- ( do they do digi / optical inputs on subs !)
..sadly the best speaker to hear any 50Hz hum on..

 

[kropaske]

I did try with earth to the casing but no joy.
Inputs are RCA but even without anything connected I got hum so it must be from AC.
Basically I need something like THAT but much smaller as only need to pull around 100w and need to fit in the cabinet

 

[static zap]

Just be wary with your "Isolated diagnosis"-Shaver socket
may not have quite been running at normal voltage ....
Hence volume was diminished.

 

[Bob Geldoff1234]

Surely,if there's a hum from the sub woofer then it's either A:- a cheap system or B:- faulty.
You shouldn't have to start messing around with transformers etc if it's brand new

 

[Midwest]

Happy New Year You filthy Animals

 

[Carl S]

I use a 2kW mains conditioning unit borrowed (permanently) from our laboratory. Something like this but it was free IsoTek EVO3 Mini Mira Mains Conditioner - MCRU - https://mcru.co.uk/product/isotek-mini-mira-mians-conditioner/?gclid=EAIaIQobChMIr5CFrvvM3wIV77XtCh1CFw7lEAQYBSABEgJ4SPD_BwE&v=79cba1185463