I have been looking for replacement stickers, those caps will have to go eventually. Unlike most other components in an amp they do NOT get better with age.
Funny you should mention that...
I have an old school Fosgate Punch200DSM which will soon make an appearance in this section.
I was going to refurb it since I thought the exact same thing (caps dry out and don't last).
Well I went off to Mouser and ordered a bunch of new replacement caps of different sizes and vendors to see which ones I like better.
I pulled the old caps out which were nice Nichicon LQ series which aren't available anymore.
I was curious how bad they were so I tested them on an LCR meter I have at work.
To my utter surprise, the 20yr old Nichicon's still tested better than my brand new replacement caps....
I tried various brands too, Nichicon, Panasonic, Cornell. Same result.
We have an OLD Sorenson DC Power Supply that was built in 1972 (>40yrs old).
Same situation, I was going to refurb it a bit to make it more reliable.
There was a huge Sprague cap on the output that I figured needed replacing.
I researched for replacements and then measured the old Sprague.
Sprague caps were LEGIT back in the day. It even has MADE IN USA stamped into it.
Anyway, I measured it and sure enough, still in spec and better than any replacement I could buy for it.
Caps back in the day were sure made different then they are today.
One would think that they'd have to be a bit dried out, but the numbers didn't lie.
If you do replace those caps, I'd be curious at getting my hands on them and testing them to see how they do (unless you ahve an LCR meter yourself or something similar)?
I don't have an LCR to do the testing myself or I would. Now that you mention all of this I am curious again... These caps are also old Elna units so I may just keep them around. I believe you have inadvertently given me another quest. Dammit again capacitors. Dammit again modern crap components. One thing that sure blows about being a broke student is the inability to afford test equipment or I'd have lots of it. Can you suggest me a sub $300 LCR, preferably a bench unit?
Elna's huh. They really made 'em good back in the day.
I'd bet money that they still measure just fine and are probably better then any new caps you could buy.
Electrolytic's are commonly spec'd with a 20% tolerance and the latest caps I've tested all measure in towards the bottom part of that 20%, even the better caps (Nichicon/Panasonic) which surprised me but I suppose they need to do that to stay competitive with the other lesser quality caps which are consuming the electronics market.
Hmmm, sorry but I don't have any experience with LCR meters in that price range. I wouldn't know how accurate they are.
Mine at work was $12k
If you do get one, I'd be happy to measure some reference samples to compare your results to.