[zambaretzu]

Just got some self-amplified Swan D1080's that are emitting a pretty bad buzz when plugged in. (Figure amplifier's the best forum, since it's probably coming from their internal amp.)


I'm somewhat electrically able and I wonder if I can get them working. Here are some clues:

• This isn't pure noise, it seems to pick up some radio and other static.
• The volume control does NOT change the volume of the buzz
• This only happens with audio cables plugged into the inputs. Buzz is only 1/10th as loud without any cables going into the RCA input. Having that cable plugged into a source vs. not doesn't affect the noise. And this happens with any pair of cables.
• They don't have a grounded power cable.

Any idea? What should I look for if I take them apart?

 

[MichaelJHuman]

I wonder if hooking up a cable is acting like an antenna. I used to have a powered sub that would play a local radio station very quietly, which is why I was wondering.


Maybe some capacitor in the speaker is supposed to reject RF, and is not working properly. I am not an engineer, so this is probably silly guesswork on my part.