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Vintage threads from the first ten years

Sprague's

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6/3/2000 8:03 PM
JC	Sprague's Hello! Is there any strong, solid, heavily thoroughly tested reason, aesthetic appart, for why I shouldn't replace those "sprague" type can caps with a couple of some other easier to find electrolytic caps (axial or radial type) of the same value? Thanks. JC

6/3/2000 8:09 PM
JC	Re: Sprague's, 2nd part. Physical size of the cans. And, please: Why do they differ so much in size? Even in the same circuit / amp, depending on where they are placed, two of the same ratings can be one "normal" sized, the other really huge. Thank's again. JC

6/3/2000 9:54 PM

All other things being equal, I awlays pick the cap with larger body. Newer materials allow the cap manufacturers to make caps smaller in size. I usually find that the higher quality caps like the Sprague Atoms have larger bodies than the cheesy ones such as the illinois caps. This leads me to conclude that part of the reason why I never have comebacks when using Spragues, and I have had illinois caps short out is related to the physical size of the caps. It may just be a coincidence, but it sure doesnt seem like one.
PS

6/3/2000 8:10 PM
Howard	Re: Sprague's Spragues are relatively cheap and easy to find... where do you live and how hard have you looked ?? Hey, you can use anything you want to, as long as the values correspond.

6/3/2000 9:38 PM

I agree with Howard, except that I feel compelled to add that the Spragues and CDE axial caps are far superior to most of the other brands of "standard" electolytic caps that I've used over the years. This was mentioned in another thread on here recently. If you test the caps before installation, you'll find that brand new Sprague caps will be very consistent. Cheaper caps(not much less expensive though) like the tiny illinois ones will have a wide variance in ESR. They also become leaky after a short time of use. The ratings on the caps are misleading. A 500Volt sprague atom has a working voltage rating of 500volts and a surge of 550vdc. A 500volt illinois cap has a SURGE RATING of 500VDC and a working voltage of 450VDC. This means that these caps are marginally suitable for use in most 50watt and 100watt amps and may explain why they dont last very long. The Sprague are worth the extra few cents you pay for them.....IMHO.
PS

6/3/2000 10:37 PM

Peter, Howard,

I think I have to look after the Spragues or similar ones a bit harder.
Where I live is hard to find a cap rated for 450 volts, so you can imagin the rest of the story.

"Why that much? haven't you got enough with 60 volts?"

"Well, it's tubes, you remember them?"

"What? Oh! yeah! those tubes, yes, I thought they were obsolete..."

So: you "may" find new Mullards for $3 (same price for Telefunkens, Brimars...), but you can´t find a 500v cap...

JC

6/4/2000 7:54 AM
Peter S	JC, If you cant find them locally, you can order them online from various websites. Triode Electronics.....Hoffman Amplifiers, etc. If you can find an electronics supply house near you, y=they should be able to order them for you. Some music stores can order them for you through New Sensor or some other distributor. Peter S

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