I don't mean to state the obvious here, but you did check all the fuses, right? It's possible your sound system is fine. That's what fuses are for, to protect against this sort of thing.

Scary part is, if the jump really did fry your factory sound system, there's nothing else you can do to protect the Empeg other than installing fuses on the power lines.

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Tony Fabris
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Tony Fabris