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Who makes RELIABLE modern electrolytic caps?

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tub...@myshop.com

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Feb 11, 2019, 1:32:57 AM2/11/19
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Changing the electrolytic capacitors in vintage tube gear is a must
these days, but no one makes the old style (large size) caps anymore.
I personally do not trust these small modern caps to last very long.
Many computer motherboards have proven how short the life span is on
modern caps, and most of them are low voltage types.

Those old caps have lasted 40, 50 sometimes 60 years. I doubt any modern
caps will last even 10 years. I tend to wonder if that is because of
their small size. Or is it just the construction or materials used?
There are some NOS (new old stock) caps available, but they fail
regardless if they were used or not, since the electrolyte drys out and
moisture may enter them as well.

I dont mind changing caps on vintage gear once, but if I have to change
them every 5 or 10 years, I will not be happy.

But since new caps are no longer made, which are made the same as the
old ones they are replacing, I have little choice but to use these small
modern ones.

That leads to finding brands which are reliable. And I assume price
tells all. Cheap imports are likely the worst, while high priced US made
ones will last longer.

I doubt any modern caps will last even close to the life span of the old
ones, but which brands are the best? (Particularly the ones used for
high voltages in tube gear).


Fox's Mercantile

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Feb 11, 2019, 1:46:06 AM2/11/19
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On 2/11/19 12:32 AM, tub...@myshop.com wrote:
> I personally do not trust these small modern caps to last very long.
> Many computer motherboards have proven how short the life span is on
> modern caps, and most of them are low voltage types.

All of the new "small modern" caps will out live you.

--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com

tabb...@gmail.com

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Feb 11, 2019, 2:21:59 AM2/11/19
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The main cause of failure for modern caps is that they're run at high ripple current, something that does not happen in valve equipment.

If you want best reliability, get 120C rated caps rather than 85 and look at their mfr rated lifetime expectancy.

If you plan to send it to the moon, for extreme reliability for small values on HT, put plastic film caps inside the old cases, choosing higher v ratings & putting 2 in series. Then vacuum pot them. This is of course not necessary :)


NT

Phil Allison

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Feb 11, 2019, 2:48:05 AM2/11/19
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** You are so full of shit.


Any of these "snap-in" types will replace the high voltage electros in tube amps with advantage. If more then 450V is needed, connect two in series.

https://www.google.com.au/search?ei=MydhXLysIZOl9QOo_r0Q&q=100+uf+450v+snap+in

Out last you for bloody sure.



.... Phil

Look165

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Feb 11, 2019, 4:45:52 AM2/11/19
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In fact, they are reliable, but due to cost reduction, some plants use
processses which do not respect the dedicated soldering process and
either the component breaks or it's value changes.
Specially decoupling caps. generally the problem is located at the
terminations.

peterw...@gmail.com

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Feb 11, 2019, 7:25:03 AM2/11/19
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Mouser.com
DigiKey.com

And any of a dozen other suppliers will be glad to take your money and send you pretty much _exactly_ what you need.

Need multi-section caps? There is AES, Parts Express and half-a-dozen others. There is a company in Germany making Cornell-type cans on OEM equipment, but using modern materials.

And CE Does it right here in the US: https://www.cedist.com/products/capacitors?filters=Brand%3DCE%20Manufacturing

Remember, it is ONLY money.

Peter Wieck
Melrose Park, PA

Ralph Mowery

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Feb 11, 2019, 10:43:50 AM2/11/19
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In article <9vOdnR5BFY21h_zB...@giganews.com>,
jda...@att.net says...
>
> All of the new "small modern" caps will out live you.
>
>
>

I would not sasy ALL. Remember the computer boards that had capacitors
on them that only lasted about a year ? A friend and I had to send back
several boards to one of the big computer board and part suppliers , but
that was about 20 yars ago.

You may say the quality capacitors will outlive most of us.

Even the big name companies have problems. I have some test get that I
bought surplus when the cell phones went from the 800 Meg to higher
frequencies. The $ 50,000 piece of gear had capacitors go bad in the
switching supplies. That was made around 1995 so they only lasted about
20 years.

I don't know how long they will last, but I just bought a lot of
capacitors from China off ebay. About a dozen of them are in use in my
equipment and have worked for the last 3 months. They may or may not go
out today. I would not put them in equipment that I was repairing for
anyone for money, but this isfor my hobby work.




Fox's Mercantile

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Feb 11, 2019, 10:49:59 AM2/11/19
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On 2/11/19 9:43 AM, Ralph Mowery wrote:
> Remember the computer boards that had capacitors
> on them that only lasted about a year ? A friend and I had to send back
> several boards to one of the big computer board and part suppliers , but
> that was about 20 yars ago.

That wasn't because of modern capacitors.
That was because the bean counters at Dell went with
cheap counterfeit caps that were shit.

Chuck

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Feb 11, 2019, 12:04:17 PM2/11/19
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Panasonic and Nichicon.

et...@whidbey.com

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Feb 11, 2019, 1:04:50 PM2/11/19
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On Mon, 11 Feb 2019 00:32:54 -0600, tub...@myshop.com wrote:

Yeah, I totally agree with you. The new smaller modern caps just can't
last. A perfect example. My Pioneer SX-434 is only 46 years old and
the shitty small caps in it must be getting ready to fail. Even though
I listen to it every day and though there is no degradation in the
tuning or the sound I just know the caps must be getting ready to
fail. They are just so small.
Eric

Ralph Mowery

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Feb 11, 2019, 1:32:16 PM2/11/19
to
In article <uMGdnZXH7K4CBPzB...@giganews.com>,
jda...@att.net says...
>
> On 2/11/19 9:43 AM, Ralph Mowery wrote:
> > Remember the computer boards that had capacitors
> > on them that only lasted about a year ? A friend and I had to send back
> > several boards to one of the big computer board and part suppliers , but
> > that was about 20 yars ago.
>
> That wasn't because of modern capacitors.
> That was because the bean counters at Dell went with
> cheap counterfeit caps that were shit.
>
>
>

The origional post was about which brands were the best.

That is why I said not all modern capacitors would last. I am sure
there are lots of crap China brands of capacitors. I probably bought
some a few months back, but they go in my hobby electronics.

The boards I sent back were not Dell. They were some boards from a
company that sold computer boards and parts that I put together a
computer. The boards were high rated before the capacitor problem. I
think lots of companies had the cpacitor problem from that particular
capacitor company.

One of the main things is that the switching supplies or high
temperature are the main killers of the capacitors.

Any of the good brand capacitors should last longer than most of us will
be around.

tabb...@gmail.com

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Feb 11, 2019, 3:05:23 PM2/11/19
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I don't think you're understanding why they died.


NT

John-Del

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Feb 11, 2019, 6:50:52 PM2/11/19
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When I build (or rebuild) something for myself, I always go with Panasonic capacitors.

Ralph Mowery

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Feb 11, 2019, 11:26:29 PM2/11/19
to
In article <0a7d888b-9f93-401d...@googlegroups.com>,
tabb...@gmail.com says...
>
> > Even the big name companies have problems. I have some test get that I
> > bought surplus when the cell phones went from the 800 Meg to higher
> > frequencies. The $ 50,000 piece of gear had capacitors go bad in the
> > switching supplies. That was made around 1995 so they only lasted about
> > 20 years.
> >
> > I don't know how long they will last, but I just bought a lot of
> > capacitors from China off ebay. About a dozen of them are in use in my
> > equipment and have worked for the last 3 months. They may or may not go
> > out today. I would not put them in equipment that I was repairing for
> > anyone for money, but this isfor my hobby work.
>
> I don't think you're understanding why they died.
>
>

I think I have a fair understanding of why capacitors die.

The could be made out of crap materials like the ones on the computer
boards.

The switching power supplies really stress capacitors and they need to
have a low ESR.


Heat will be bad for them. Some are rated around 85 and some are rated
over 100 deg C.

The voltage ratings should be in the correct range. If they sit around
a long time some will need to be reformed to meet the voltage
requirement. Some of the capcitors are formed at a higher voltage than
they are rated for to insure that as they age on the shelf they will
still meet the rated specifications when used year or more later.


Chuck

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Feb 12, 2019, 1:03:58 PM2/12/19
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When you finally have a failure, I would replace all Sanyo brand
capacitors.

tub...@myshop.com

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Feb 17, 2019, 3:11:13 AM2/17/19
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Yes, the original question was which caps are BEST, but much of my
concern is based on the failed motherboards, which only lasted a year or
so.

Knowing the name used on these really bad junk caps would be useful to
know too. I'm pretty fussy when I buy caps and some other components,
but I do sometimes buy "grab bags" (like on Craigslist) if the price is
right, and I know some parts will be usable. But knowing the name used
on those conterfeit caps, or any others known to fail is good to know.
If the caps are known bad, I am not going to use them for anything other
than a breadboard test design, (or not at all).

I'm curious what brand of motherboards were the bad ones too....

It's just good to know things like this. Just like every brand of car
seems to have certain common failure or breakdown problems, and knowing
what to check and watch for, is helpful.


dl8...@dl8fbh.ampr.org

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Feb 17, 2019, 11:00:08 AM2/17/19
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tub...@myshop.com wrote:
>
> That leads to finding brands which are reliable. And I assume price
> tells all. Cheap imports are likely the worst, while high priced US made
> ones will last longer.
>

Electrolytics from Panasonic

Mike

Fox's Mercantile

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Feb 17, 2019, 5:13:03 PM2/17/19
to
On 2/17/19 2:11 AM, tub...@myshop.com wrote:
> Yes, the original question was which caps are BEST, but much of my
> concern is based on the failed motherboards, which only lasted a year or
> so.

Which, as usual, you didn't make at the beginning.

The Failed motherboards were, Dell.
Their "Lets buy cheap shit" almost put them out of business.
And that was almost 20 years ago.

Phil Allison

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Feb 17, 2019, 6:06:01 PM2/17/19
to
Fox's Mercantile wrote:
>
>
> tub...@myshop.com wrote:
> > Yes, the original question was which caps are BEST, but much of my
> > concern is based on the failed motherboards, which only lasted a year or
> > so.
>
> Which, as usual, you didn't make at the beginning.
>
> The Failed motherboards were, Dell.
> Their "Lets buy cheap shit" almost put them out of business.
> And that was almost 20 years ago.
>

** This old Wiki has the story:

https://en.wikipedia.org/wiki/Capacitor_plague

The brands of capacitor involved were previously unknown and unable to be linked to any of the well known makers.

AFAIK the issue never involved electros that might be used in restoration of vintage tube gear.

"tubeguy" is a fuckwit - see " top definition " :

https://www.urbandictionary.com/define.php?term=fuckwit



.... Phil

Michael Black

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Feb 17, 2019, 6:41:40 PM2/17/19
to
A little knowledge can be a dangerous thing.

People hear the stories, but don't grasp the details. Modern use of
electrolytics is different from the tube days. Not only have values gone
up as size got smaller, but they are often expected to handle much higher
frequencies than 60 or 120Hz in the days of tubes. Electrolytics are also
a lot more common in the days of solid state. In tube days, a bad one
would mean low voltage, or hum, or low audio gain, but there were a
handful of electrolytics. Now they are everywhere, a shift to low
impedance so larger values needed, and that means electrolytics. The
circuitry is now more complicated and a bad capacitor may not be so
obvious as in the old days.

Michael

whit3rd

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Feb 17, 2019, 8:05:10 PM2/17/19
to
On Sunday, February 17, 2019 at 2:13:03 PM UTC-8, Fox's Mercantile wrote:

> The Failed motherboards were, Dell.
> Their "Lets buy cheap shit" almost put them out of business.

Oh, no, it's not that simple. Dell was publiclly traded, and made formal notice
in their stockholder report one quarter, and that was big news. But, Apple
had similar problems (trust me, I own a couple or three), as did everyone else.

The faulty technology was widely rebranded and even given counterfeit
labeling, and wasn't purged from inventories for some years.

The bad capacitors weren't significantly less expensive than any others on
the market, and turned bad only after a year or so (so incoming tests couldn't
catch the problem).

Ralph Mowery

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Feb 18, 2019, 12:02:52 AM2/18/19
to
In article <d1189f6f-4996-46ef...@googlegroups.com>,
whi...@gmail.com says...
>
> Oh, no, it's not that simple. Dell was publiclly traded, and made formal notice
> in their stockholder report one quarter, and that was big news. But, Apple
> had similar problems (trust me, I own a couple or three), as did everyone else.
>
> The faulty technology was widely rebranded and even given counterfeit
> labeling, and wasn't purged from inventories for some years.
>
> The bad capacitors weren't significantly less expensive than any others on
> the market, and turned bad only after a year or so (so incoming tests couldn't
> catch the problem).
>
>

Yes, it was not only Dell,but other companies. I and a friend had a
mother boards that were bought as boards and were not Dell that the
capacitors went bad. Those boards were highly recommended before the
capacitor problems showed up. Just lucky it was less than a year and
under warrenty. I had a video card or two that had the capacitor
problem.

tub...@myshop.com

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Feb 25, 2019, 11:59:35 PM2/25/19
to
On Sun, 17 Feb 2019 16:12:53 -0600, Fox's Mercantile <jda...@att.net>
wrote:

>On 2/17/19 2:11 AM, tub...@myshop.com wrote:
>> Yes, the original question was which caps are BEST, but much of my
>> concern is based on the failed motherboards, which only lasted a year or
>> so.
>
>Which, as usual, you didn't make at the beginning.
>
>The Failed motherboards were, Dell.
>Their "Lets buy cheap shit" almost put them out of business.
>And that was almost 20 years ago.

It dont surprise me it was Dell. A friend had a Dell that was from the
early 2000s. It had XP on it. It was so frikkin slow I could literally
outtype it, using notepad. She asked me if there was something wrong
with it. I changed some settings and that did nothing. Since there was
nothing on the computer except a few free games, I formatted the hard
drive and reinstalled XP. Still slow.....

Heck, I had a much older and lower powered computer at the time that was
running Windows 98, which was 10X faster than that Dell.

A few years later I got an almost identical Dell computer given to me. I
installed XP on it and was shocked to find it was just as slow as the
friend's computer. I didn't even bother with it any further. I removed
the drives and sent the rest of it to the recycler....

Things may be different with Dell today, but I will never buy any Dell
computers, new or used, after that experience.

I strictly use all IBM/Lenovo computers. They last forever. I still have
one that works fine and is 20 years old. My newer ones I own are great
too.

Fox's Mercantile

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Feb 26, 2019, 12:49:58 AM2/26/19
to
On 2/25/19 10:59 PM, tub...@myshop.com wrote:
> Things may be different with Dell today, but I will never
> buy any Dell computers, new or used, after that experience.

Dell like most PC suppliers have a wide range of models, from
cheap to high end.

It's like saying "I'll NEVER buy another Ford product" because
of the Pinto, or "I'll NEVER buy another Chevy product" because
of the Vega.
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