Question about NAD C370 2-Channel Amplifier

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One (right) preamp blow! I've located the problem to the right C160 module. When disconnected everything seems fine. Diodes and transistors are apparantly ok measured onboard as are all resistors and nothing seems "burnt". Power on and the output is nearly 33 volts - the healthy channel app. 0 volts

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  • Rommel Cana
    Rommel Cana Oct 01, 2010

    then here are additional things to check:
    http://www.fixya.com/support/t5934610-na...

    same withe driver transistors

  • jacob_r Oct 05, 2010

    Well, thank you petraman7! I was working on it while you posted, The Amp is up and running by now. It turned out only "upper" output transistor was blown. It really had me puzzled for a while as the diode characteristics of that transistor was identical to that of the healthy channel. I changed all transistors by the way just to be sure and a single electrolyte capacitor as well.

  • jacob_r Oct 05, 2010

    Hi Petraman7 Actually your input arrived to me 1 hour "post festum".
    Your solution was the right one though. So the helpful rating is there for everyone ...else!

  • jacob_r Oct 05, 2010

    Hi Palaboy7
    The "C160 module" is just the name for the an input stage in the preamp section - not too much heat generated here I think. (Got schematics from hifiengine.com)

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Hi...
transistors are not ok on the C160 module.
replace all the power transistors and emitter resistors for that channel.
www.bdent.com and www.ceitron.com are good for transistors

Posted on Oct 04, 2010

  • Scott Frye
    Scott Frye Oct 05, 2010

    glad I could help

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