OBXA PSU caps ,"Low impedance caps"?

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Skiroy

Well-known member
Joined
Apr 13, 2010
Messages
233
Location
Panama City Florida
Rebuilding the OBXA PSU finally and been doing research on Caps. I read Audio grade is not neccessarily the best choice and the more important spec is the ripple current rating for PSU caps. Keeping in mind that Im trying to stay with 105C caps I found what appears to be a super caps. It has 8000hrs life and high ripple current rating. The only confusion is its categorized as a "low impedance cap" and I dont know if that is acceptable or not in this application. Here is the Cap.

http://www.mouser.com/ProductDetail/Nichicon/UPW1V472MHD/?qs=sGAEpiMZZMtZ1n0r9vR22eD8a%252bFprAqc3edjQfR4mzk%3d

Thankx
 
High ripple current and long life is a result of low impedance design. Equivalent series resistance (ESR) causes heat dissipation with AC currents, which in turn limits the maximum ripple current and shortens life (as the capacitor dries out faster at high temperatures). So low ESR = low impedance increases maximum ripple current and life time.

Samuel
 
Okay so Im down to getting my caps for the voice cards. Here is the service manual.

http://www.lazyblueoctopus.com/oberheim_obxa_service_manual_3.pdf

Now everyone says to go with higher Voltage caps. I did throughout the PSU and motherboard. I really want to stay as close to the original caps as possible in the audio path. Im wanting the Elna Cerafines as they are known to be more aggresive and thats what the OBXa is all about. The issue is the 35V versions of today are to large and I would have to go with 25V for them to fit. The originals are 35V.



Now scotrod is a very knowledgable guy and said that the audio path does go above 11V and the power rails do not go above 15V, 25V would be fine. But most of what I read says to get higher voltage caps than originals and if the originals are 35V Im weary about getting 25V. But I have the utmost respect for scotrod and I know nothing ,but I would like to get some of your opinions after looking at the schemo of the voice cards on page 56.
 
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