LM3886 gone crazy!!

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I opened up the back of my subwoofer built using a lm3886 and noticed that a wire from the transformer had fallen off of the rectifier, leaving only 1 wire and the CT connected. Yet, the amp still worked. It was only getting either + and gnd or - and gnd, but it still worked. How could that be? I built the split supply version, but it was working off of a single supply??

-Mike
 
I opened up the back of my subwoofer built using a lm3886 and noticed that a wire from the transformer had fallen off of the rectifier, leaving only 1 wire and the CT connected. Yet, the amp still worked. It was only getting either + and gnd or - and gnd, but it still worked. How could that be? I built the split supply version, but it was working off of a single supply??

what happened there was that with one wire gone, you still had +/- rails because there is still one wire from the traffo and the ct going to the bridge rects, so you had a voltage-doubler in operation, what this meant was that the supply had a higher regualtion %, meaning the rails sag lower than with the other wire connected, less va from the traffo can be utilised in that case...
 
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