When I touch an audio, and only the jack, I can hear the radio through the speakers. Anyone know why?

Question

I'm only touching the audio jack and my bed. The speakers are simply plugged into the wall, and the jack is unplugged. Usually all I hear is static when I touch it or it hits metal, but if I hold it and apply minor pressure to the jack, I can hear the radio through the speakers. I'm not sure how an audio jack works, but found this very weird.

Answer 1

It's not something special about the audio jack, just has to do with wires and conducting current (including through you and the bed maybe).

You basically created a simple crystal radio antenna with the speaker wire - this happens (somewhat infrequently) whenever there are lengths of conducting wire and some form of speaker.

My wife works on a fireworks crew and they picked up a radio station on the fireworks shooting board last month (wires go from the board to each firework) - instead of a beep they heard the sports news :)