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PostPosted: Wed Sep 20, 2017 4:32 pm 
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Joined: Sun Nov 11, 2007 5:30 pm
Posts: 1
Location: National Capital Region, QC, CA
Thinking of recapping your Sansui integrated amplifier ! I've been doing it for years and it does pay off . I'm talking about 70's and 80's units AU-517 / 717 , AU-719 , AU-919 , AU-20000 are the most popular units that came across my bench . The first caps that go are the electrolytics on the power supply and power amp boards because of heat , never mind the tone control pre-amp or flat amp those hardly ever fail but if you want a total recap job then do them also . Having the service manual helps but they have errors so always replace with the same value that's on the board and in the same polarity don't trust the silkscreen on the board they also have errors . Same capacitance is a must but voltage can be higher . If you see the odd Tantalum leave them they never fail . Don't waste your money on high grade audio capacitors most capacitors in your units are regular caps that have worked for 30 or 40 years high grade won't last longer . Most caps in these units are for DC filtering anyways . I personally use Nichicon PW or PM series they are higher quality than the original ones in any of the models listed above . I keep an inventory of about 650 caps in stock all values and up to 160V that way whatever make or model lands on my bench I can finish it the same day . It's not that hard to do , so good luck and enjoy . While you're in your unit make sure to check the protection relay and don't forget to tweak DC offset and Bias .


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PostPosted: Wed Sep 20, 2017 5:56 pm 
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Joined: Fri Feb 09, 2007 4:13 pm
Posts: 6312
Location: Fisher Branch, MB, CA
Thanks for the tips. I don't have a Sansui integrated but my Beard P-100 tube amp is being restored right now with new caps and out of spec parts replaced. After 30 years she was in need of some tlc.


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PostPosted: Fri Sep 22, 2017 6:05 am 
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Joined: Wed Nov 27, 2013 1:31 pm
Posts: 18
Location: Eastern Passage, NS, CA
The biggest thing to do when servicing these units is getting rid of those damn VD1212 diodes with 2x 1N4148 diodes in series.

Dipped tantalum capacitors definitely do fail, especially in this vintage of equipment. When they fail, they short. If any are used for decoupling power supply rails, they should be replaced. I've seen this quite often, especially in 70's test equipment. Ceramic caps on the other hand rarely fail.


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PostPosted: Fri Sep 22, 2017 7:05 am 
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Joined: Sat Feb 12, 2011 8:14 am
Posts: 77
Location: Windsor, ON, CA
>> Same capacitance is a must but voltage can be higher.

This is not entirely correct. :(
--
There are numerous locations in these Units...

Where the Capacitance can safely be increased (and therefore should be increased) --
If you 'truly' want the very best out of these respective, Sansui Integrated Amplifiers.

http://audiokarma.org/forums/index.php? ... 17.641945/

Thank-you!


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