Question about NAD C370 2-Channel Amplifier

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Climbing DC offset then protection mode

When I switch this amp on it will produce soung for a short while, 30 seconds to a  minute and a half before the protection circuit kicks in. DC offset begins at zero and has reached 425mV.

Any suggestions as to the likely solution?

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Hi there

Firstly, check for conductive hold down glue about the output stages. This can cause the problem you have. Or there may be a failing component somewhere in the output stage of that channel. Check for leaky transistors,diodes an capacitors. You will need to remove semiconductors to check for leakage, If you dont have alot of experience faultfinding amplifier power stages, I suggest you take it to a NAD authorised service center.

regards
Graeme

Posted on Apr 06, 2008

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