Question about Denon AVR 3808Ci Receiver

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Amp problem, blown channel?

I have an ancient Pioneer sa-900 amp. I dug it up from my dads garage and it probably hasn't been used in 25 years. When I hooked it up it started out fine, but seems to fade out on one side after awhile. I was told it was probably a blown channel. Any expertise on the subject would be greatly appreciated. I'm wondering if it would be worth taking apart and trying to fix.
Thanks, Lindsay

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  • Cruckshank Oct 25, 2008

    Thank you mistersony and benimur for the advice, much appreciated. I will try cleaning it like u say and let you know what happens.


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I would bet that your problem is more likely caused by the long sit and less a blown channel. First thing I would do is take the unit apart and clean all of the switches and controls with something like Caig Labs R5 (available from MCM electronics and from Amazon). Pay special attention to the tape monitor switches and the speaker relay, as those are the most common causes of lost sound on one channel. The easiest way to clean the speaker relay (once you have the cover off) is to take a sheet of plain white paper, cut a thin strip off and saturate it with the R5 and then slide it through the relay contacts witht relay closed. I'll bet after you do taht, you'll see that the paper has black streaks where you have cleaned corrosion and oxidation off the relay contacts.

Posted on Oct 24, 2008

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  • Master
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Hi,

Congratulations, the Pioneer SA-900 is already a classic, a legendary pre-amp/amp unit. It is not as high powered as today models but certainly can hold its own. Offhand, there would be three (3) ways you can attend to the concern:

  • perform a DIY (do-it-yourself);
  • seek the services of a reputable audio shop;
  • seek the services of a professional classic audio equipment restorer.
Should you be considering a DIY, it might be to your advantage to have access to a service manual. This of course requires familiarity with electronic components and circuitry, use of a DVM and a soldering iron.

This might be informative.

Hope that this be of initial help/idea. Pls post back how things turned up or should you need additional information.

Good luck and kind regards. Thank you for using FixYa.

Posted on Oct 24, 2008

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