Ferrite install on appliances AC cable

I've tried ferrite "circles" around appliances, including the refrigerator. Didn't have any effect on the audio system. However, that was years ago and the system is way more revealing now. I still have the ferrite thingies ... maybe I'll try them again. 

Frank

Ferrites are best for high frequency noise, including radio stations and other EMI/RFI.
Their best use is if you have wall warts, like for your network, or Class D amps. They are good on fluorescent lamps, but man, they can put out so much noise that it's only a slight improvement there.

Do not use on your system as they are bad for the dynamics and sound.