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Experience on replacing capacitors of SS preamp?

I have done replacing blown resistors from a tube amp before, but not capacitors.
Replacing capacitors would be as easy as replacing resistors?
I will have an old SS AR preamp which is over 20 years old, and am thinking about replacing all caps by myself, but I'd like to hear any caution or tips of doing the job.

thx

128x128ihcho
ihcho's avatar
ihcho OP
612 posts
 
Thanks for the tips.
orpheus10
8,668 posts
 
Draw a diagram of what it is you're going to remove before you go to work.
ihcho's avatar
ihcho OP
612 posts
 
The preamp is AR LS3.
The schematic is available on line. https://www.vintageshifi.com/repertoire-pdf/pdf/telecharge.php?pdf=Audio-Research-LS3-LS3B-Schematic...
There are 32 capicators. All of them need to be changed?
boxer12
8,656 posts
 
Depends. What is your purpose for replacing them? Is there an issue with the preamp or are you wanting improved sound? 
erik_squires
16,332 posts
 
Avoid changing caps in the signal path (shouldn't be any).
Find a 10K resistor or so to help you discharge caps. They can hold those very high voltages for a long time. Measure V before touching them. Use a resistor to discharge safely.

Ensure replacement caps:
V = or > originalTemperature = or greateruF = identical.

The uF in the primary filter caps can be a little larger (uF) but don't go nuts. You stress the transformer and bridge rectifier.

Higher Temperature = longer life.

Triple check polarity on removal and installation.

No, you only want to replace electrolytic caps in the power supply. Changing the film caps is not necessary and can affect sound and retail value.
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