My 8 y/o speakers turned to a radio?

[madmisha]

Hello members of this awesome looking science forum! I'm Misha. ...an educated general physics novice!

I came here after running into a very strange phenomenon. ...all off a sudden my good old trustt speajers stopped responding to the information sent to them from the conputer and instead begun playing sobering off a local radio station...it was rather weak, I had to turn them to max volume to hear properly. ... it kept going even when the pc was off. ... even when the speakers were unplugged from the pc...the speakers have no radio receivers in them. ...
What the hell is going on?

I know when you turn most speakers v really high they make a radio like white noise. ... so do speakers actuallt have some kinda frequency of their own and that radio station just hit things right with that of mine?
Thanks for the help

 

[berkeman]

Hello members of this awesome looking science forum! I'm Misha. ...an educated general physics novice!

I came here after running into a very strange phenomenon. ...all off a sudden my good old trustt speajers stopped responding to the information sent to them from the conputer and instead begun playing sobering off a local radio station...it was rather weak, I had to turn them to max volume to hear properly. ... it kept going even when the pc was off. ... even when the speakers were unplugged from the pc...the speakers have no radio receivers in them. ...
What the hell is going on?

I know when you turn most speakers v really high they make a radio like white noise. ... so do speakers actuallt have some kinda frequency of their own and that radio station just hit things right with that of mine?
Thanks for the help

Welcome to the PF.

Are you talking about powered speakers here? If so, does the sound go away when you turn them off?

If you have a strong enough local broadcast radio station, the high level of EM energy can be picked up by parts of the amplifier circuit, and you can hear the audio at a low level. I had a situation in my home EE lab when I was consulting where I was picking up a local AM broadcast station around 1MHz, and it was playing quietly through an amplifier I was working on.

Can you tell what station it is by using a regular radio to match the music? If so, note their callsign letters and frequency, and do a Google search to see how far away their broadcast transmitter is from you, and what power level they are transmitting.

 

[russ_watters]

I did a study on a building that acted as a receiver for the radio station across the street. Yeah, that's right: if you put your ear to the metal window frame, you could hear the radio broadcast (on a particular floor). Needless to say, everything with a speaker on that floor was also tuned to that station. It was a big problem that never got solved.