My friends subwoofer started to hum and the membrane went into its most inner position.
I replaced the amplifier chip TDA7294 because it draw the supply rails down and let DC to the driver.
After replacement the supply rails are ok at +-27v, but the output is +25,5v without driver and the rails are +23,5v -25,5 and output is +5v with the driver connected.
Bad chip I thought and replaced it again, but same result.
Components around TDA7294 seems ok, and no DC in signal path.
Anyone have a clue what is going on, and maybe know where to find a schematic.
Tonny
I replaced the amplifier chip TDA7294 because it draw the supply rails down and let DC to the driver.
After replacement the supply rails are ok at +-27v, but the output is +25,5v without driver and the rails are +23,5v -25,5 and output is +5v with the driver connected.
Bad chip I thought and replaced it again, but same result.
Components around TDA7294 seems ok, and no DC in signal path.
Anyone have a clue what is going on, and maybe know where to find a schematic.
Tonny
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