Yes, i searched. No real explanation of this phenomenon.
Actually, its not real problem, just curiosity. Nothing is broken.
Let me explain. This hum happens in numerous instances, various combinations of mp3 players and amplifiers. Mp3 players are all battery powered. In garage system, or traveling system, various classD amplifiers. Big or small speakers, does not matter. While mp3 player is on, there is no hum. When its off, there is hum. When i unplug cord from mp3 player, no hum. Maybe slight static, depends what amp and where the volume is set.
Any idea why the mp3 player generates hum when its off? There is no hum the moment its turned on.
Actually, its not real problem, just curiosity. Nothing is broken.
Let me explain. This hum happens in numerous instances, various combinations of mp3 players and amplifiers. Mp3 players are all battery powered. In garage system, or traveling system, various classD amplifiers. Big or small speakers, does not matter. While mp3 player is on, there is no hum. When its off, there is hum. When i unplug cord from mp3 player, no hum. Maybe slight static, depends what amp and where the volume is set.
Any idea why the mp3 player generates hum when its off? There is no hum the moment its turned on.
Uh, when the player is powered off, the output buffering device goes high Z and the little bit of wire past the output jack connecting to it picks up AC magnetic field?
If you took your traveling system - battery powered - out in the middle of a big field, far away from anything AC and it still did it, I;d give up.
If you took your traveling system - battery powered - out in the middle of a big field, far away from anything AC and it still did it, I;d give up.