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Wish to upgrade phono preamp caps and other

Looking at my PS Audio GCPH I see 4 12000uf NCD caps sitting in what I believe to be the signal chain.

I wish to upgrade to best possible caps in that location.

I'm finding it difficult to locate any 12000uf caps let alone some really good ones that will fit in about a 35mm wide X 45mm high location.

I understood there are companies that replace these caps with Muse but Muse doesn't make that value cap.

I'm not electronic savvy but shouldn't you replace with same value cap?
128x128desalvo55
13 responses Add your response
riley804
1,224 posts
 
http://forum.audiogon.com/cgi-bin/fr.pl?htech&1299430867
jeffreybehr's avatar
jeffreybehr
805 posts
 
Don't change anything in your preamp until you have a schematic diagram and understand what you're doing...unless you don't care if it works. :-)
.
desalvo55's avatar
desalvo55 OP
252 posts
 
I doubt that I'll find a schematic on this phono preamp. I know the risks involved, that's why I asked the question.

I don't wish to change the circuit, just perform some upgrades such as caps, fuse, some resonance material, maybe upgrade some wiring.

That being said I should leave well enough alone, I rarely do ;)
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desalvo55's avatar
desalvo55 OP
252 posts
 
Yes the 12000uf caps are for the power supply. Probably shouldn't touch those. The remaining 4 100uf 6.3volt caps are in the signal chain. Those I'll "touch".
Thanks for your help.
Post removed 
desalvo55's avatar
desalvo55 OP
252 posts
 
My old eyes aren't what they used to be. Now I'll have to open her up and recheck but I'm 90% sure they were 100uf. How can one tell the difference between electrolytic and film?
johnss
564 posts
 
12000 uf sound like Power supply caps. You are not going to be able to stuff a film cap in place of those. Your best bet is to bypass each of those caps with a .47uf, a .22uf ad a .01 uf film and foil. dont use metalized film, make sure you are getting film and foil.

best
desalvo55's avatar
desalvo55 OP
252 posts
 
I rechecked the values of those caps. They are in fact 100uf 63volt caps. Here is a pic of the caps on the board.

http://www.flickr.com/photos/9751465@N05/5511871969/

Pictures worth well, you know.

When bypassing, I assume that means adding in parallel, the fore mentioned caps?
Post removed 
johnss
564 posts
 
"When bypassing, I assume that means adding in parallel, the fore mentioned caps?" Yes, that is what it means.

best.
ebm
9,311 posts
 
Great Northern Sound is great for this.
desalvo55's avatar
desalvo55 OP
252 posts
 
Thanks Johnss. I'll head in that direction.
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