Sprague electrolytic caps

[evil79]

So, much like most techs, I've moved on from Sprague atoms as filter caps because of cost and the fact that their shelf life is running out. I do, however, still use them for cathode bypass and bias caps. But they don't make them anymore, right? So they gotta be getting old on the shelf as electrolytics do. I've moved on to F&T for filter caps, but what do you guys use for cathode bypass, etc? Are Xicon any good? Anything axial from Mouser any good? I'd love to know what everyone else is trusting these days. Especially of its inexpensive.

[Leo_Gnardo]

AFAIK Atoms are still made, BUT what's inside them isn't the same as what they were made of "back in the day" when they earned a good reputation. I dunno if you saw yesterday in the thread about Low Impedance Capacitors:



One of many in a 2013 thread over at our friendly neighbors The Amp Garage.

http://ampgarage.com/forum/viewtopic...5d2794a244456e

In case you decide to have a look & encounter any blarney from Google - "caution malware site" like that, just push past the well meaning guards & peep all you want, there's no malware. Someday TAG will get this fixed...

Not only has Sprague been loading their Atoms shells with modern style caps, there are counterfeits made in China, and all sorts of other capacitor hijinks.

If you buy from a trustworthy source like our major US parts dealers, Mouser, DigiKey, Newark (and not from cut-price ebay sites in China, HongKong & other far east sites) there's a good chance you'll get the real McCoy when you're buying parts of all sorts.

I've found Xicon to be perfectly good, no failures in all I've used. Xicon is Mouser's house brand so you won't find 'em anywhere else. However I think they may have retired that brand. In the Mouser catalog you can find Nichicon, I've gotten their electrolytics for bias and up to 450V, axial style a little expensive but all good. Panasonic makes perfectly good metallized polypropylene, radial but leads long enough to reach for most any purpose, a good sub for favorite Xicons. And Mouser still has Mallory 150 mylar caps - Mallory was bought by Cornell-Dubilier so that may help you locate them. I happen to like the M150's a lot, still apparently made as they were found in mid 60's Fenders "back in the day" less the blue plastic shell, now a white cylinder, axial leads.

Inexpensive, well you get what you pay for. The Panasonic MPP's certainly are a bargain especially if you buy 100 or more at a time. Anything else, prices are up across the board, be happy good parts are still available at all, especially in axial form but you pay a premium for axial these days. If you don't mind bending leads on radials or just designing them into new builds, there's a savings to be had. The only deal these days seems to be at the gas pump. Even groceries are going up like they did in 2007 .

[ThermionicScott]

As I understood it, capacitor manufacture has advanced quite a bit in the last few decades and the only reason Sprague Atoms are still big on the outside is to satisfy the vintage-weenies. Can you blame them?

[drewl]

Ha,
I find the xicons to be fine and less expensive but the Mallory/ Cornel's are cheap too.

I tried explaining to one corksniffing customer but he's convinced the Fender blue caps sound much better than the Mallory's.

[Leo_Gnardo]

As I understood it, capacitor manufacture has advanced quite a bit in the last few decades and the only reason Sprague Atoms are still big on the outside is to satisfy the vintage-weenies. Can you blame them?

And there are folks who pry open old non functional caps, stuff 'em with new ones & put 'em back in their amps. Easier to do with the cylindrical cardboard covered caps. Somewhere on Audio Asylum there's a photo series where you see an aluminum twist-lok sliced open with a pipe cutter, scooped out, reloaded & put back into use. That's all very nice but I'm too lazy to go thru the process. FWIW there are some "pencil" electrolytics now that would suit the purpose well, long skinny caps with ratings up to 450V.

[defaced]

I run Nichicon for most of my caps filter and cathode bypass caps - from Mouser. Sometimes I end up with Xicon or United Chemicon if there's a reason, but Nichicon has a large selection of sizes, form factors, and some are tailored to specific applications, so I order those mostly.

[Leo_Gnardo]

I'd love to know what everyone else is trusting these days. Especially of its inexpensive.

More, if you're a biz and get an account with MagicParts/Ruby, they have a line of excellent electrolytic caps at reasonable prices. I get 'em typically 25 or 50 or even 100 at a time for a quantity discount. Only one failure in many hundreds: the label was on backwards, oops. Perfectly competent 22 and 47 uF 500V available here, cheap & moreso in quantity.

[gbono]

Sprague Atom = Vishay TVA Atom
Sprague Orange Drop = CDE (Cornell Dubilier) Orange Drop but also see DMT and DME

Please convince me that the reliability and consistency of current aluminum electrolytic and metalized film (PPS, PEN and PET) capacitors doesn't contribute to a better component in any design. I'm guessing that if most "experts" submitted to a hearing evaluation and they did rigorous/repeatable ABx comparisons (see S. Linkwitz, F. Toole, etc.) there would be less subjectivity and marketing hyperbole running the show.

[The Dude]

You might be surprised at how many people hear with their eyes.

[gbono]

or the wallet

[tedmich]

MUNDORF-76476
100µF / 350V, Mcap EVO - Silver / Gold & Oil Series, 75mm W x 50mm L, Each
$416.38 USD each

or

Dueland Cast Silver Capacitors
http://duelundaudio.com/cast-capacitor/
Quote:
"The Duelund CAST Reference Silver Capacitor is our no holds barred flagship capacitor.
The construction builds on the foundation of our Virtual Stack Foil design but does so with the addition of a proprietary WPIO dielectricum which necessitates several days of impregnation under high pressure."

if had "proprietary WPIO dielectricum" the wife probably would have required "several days of impregnation under high pressure" as well...

[Leo_Gnardo]

MUNDORF-76476 100µF / 350V, Mcap EVO - Silver / Gold & Oil Series, 75mm W x 50mm L, Each $416.38 USD each

if had "proprietary WPIO dielectricum" the wife probably would have required "several days of impregnation under high pressure" as well...

More likely the wife would be on the blower to her lawyer if she caught you spending good money on this sort of thing. "And you have to wire two of 'em in SERIES to filter your dam' high voltage? I'LL SHOW YOU SOME HIGH VOLTAGE, DARLING!"

[Chuck H]

I sometimes use tantalum caps for preamp cathode bypass. Not the little blobs that look cheesy and smell like death when they blow (and they do blow). The solid tants made by Kemet. Like the T322 series shown here:

http://www.mouser.com/catalog/catalogusd/648/1166.pdf

I saw them used in some Mesa amps and thought I might give them a try. I've never had one fail in twenty years and that doesn't touch their life span. So, one less thing to think about later when replacing all the other electrolytics.

[tedmich]

Cathode bypass is probably the only safe place in tube amps for Tants; very little stress/heat there. Kemet says some of their polymer/ tants are "less of a fire hazard" but they still can undergo "field crystallization" (boom)
A 50% voltage de-rating is always a good idea. I sometimes use tants with old school linear regulators.

[Drewline]

I've had good luck using F&T caps from CE.