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Capacitor Size

I'm curious to know about current capacitors vs. vintage caps...

Are current capacitors physically smaller than equivalent capacitors from back in the day?

The reason I ask is b/c I had an old amp recapped and the new caps are quite a bit smaller than the old ones. The tech said that new caps are physically smaller than old style caps of the same capacitance... He also went on to say that the ones he used in my amp are of even higher capacitance than the old ones... (even though they are only about 2/3 the size of the old ones).

Have I been snowed, or are new caps actually smaller than old, equivalent versions? (i can't physically see the caps' specs because of the way they are mounted).

Any insight would be appreciated. Thanks!
loose
jallen
502 posts
 
Depends entirely on the brand. More voltage spec usually means a bigger cap. Old vs. New is not the issue. Have a look at a V- Cap or a Mundhorf. Both anything but small, and current production. The small caps today that are good are Rel Theta or their polystyrene RT. Both are very good for the price. Quality matters. I hope the quality of caps is good you had installed. The quality does matter, but they have to fit. If a V-cap will fit they are the best imho. The amp has to be good enough to benefit though. A trashed antique with old wiring etc. will see a smaller benefit than a full restoration. Jallen
charles1dad's avatar
charles1dad
10,250 posts
 
The type of capacitor matters also. For example a paper in oil(PIO) cap will be larger in size than most poly film caps. Caps that are made with damping considerations may be larger and heavier such as the Duelund capacitors.
ths364
181 posts
 
I've re-capped several vintage amps recently, and the new electrolytic caps are indeed smaller in most cases. So no, as long as he used a quality brand of capacitor from a reliable supplier, you should be good to go. Happy listening!
mlawitm's avatar
mlawitm
67 posts
 
A cap is a cap. They come in various sizes depending on manufacturer. Caps are measured in mfd and they're marked on the cap for tolerance. I do know that the caps currently made today go out of tolerance much quicker than older caps. I would have had him test the caps on his meter and prove that they needed to be replaced.
loose OP
239 posts
 
I know that the capacitors he used were not particularly expensive/ high end, as he stated that they would still be an improvement over the old ones.

I've physically tried to look at the capacitors' specs, but can't read what it says on the cap b/c of the way they are mounted.

I'm going to try to dig up the old paperwork to see if that tells me anything.
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