old capacitors (in their day) vs new

[ConradH]

Well, according to Arthur C. Clarke's third law, any sufficiently advanced technology is indistinguishable from magic.

AFAICT, electrolytic capacitor design, like all design, is stuck in a box. You can improve one property, but only at the expense of others. For example, you can improve esr by increasing water content, but at the expense of higher DC leakage and shorter lifetimes. Better chemistry and materials has slowly improved everything, but I try to choose parts that aren't too specialized to a narrow application. I avoid ultra low esr caps designed for switching supplies, preferring moderately low esr high temp, higher voltage caps, for most 60 cycle supplies.

 

[Djcoolray]

One of the best capacitor producing companies and one of the oldest is Sprague made in the USA. They have the best product for recapping.....

 

[ConradH]

"Don't be vague, ask for Sprague", their slogan from way back.
Like so many other companies, now owned by Vishay. I bought some Sprague caps recently and was surprised at how good the measurements were. They seem to care more about their axial products than many others, who don't seem to want to make them at all.

 

[petehall347]

vishay is also Philips .

 

[jdurbin1]

You seem prone to jumping to conclusions based on limited data. Among other things, unlike car dealers there is really no "profit center" for repairing car amps. Just not enough money in it to make it a corporate objective, unlike car service which often produces more profit for a car dealer than selling cars. If they're using crap parts there are plenty of other more likely reasons including focus on cost vs. reliability, poor quality sourcing, vendors subbing lower quality parts, etc. etc.

You also seem prone to generalizations based on limited data. Do some car amplifiers have crap caps in them? Sure, more than likely. Does that mean it's universally the case? No, not at all.

I suppose to some extent I am also guilty of both with my comment above on low profile caps... but, at least it was an opinion based on a lot of different examples I've encountered of those failures over decades of exposure. There's a whole generation of Toyota OEM car radios that loses audio due to one of those caps leaking and eroding the mute control trace so badly it goes open circuit, as another example. You can pretty much count on that happening to every one of those radios, over time.

However, I am sure there are lots of examples of more normal profile caps leaking and no real statistics to back it up one way or another. Still, when you see a particular design over and and over again and the other normal caps - even the ones in the "runs hot" power supply don't physically leak over 20-30 years but a high percentage of the low profile ones do, it does beg the question.

John

 

[yotems]

You seem prone to jumping to conclusions based on limited data. Among other things, unlike car dealers there is really no "profit center" for repairing car amps. Just not enough money in it to make it a corporate objective, unlike car service which often produces more profit for a car dealer than selling cars. If they're using crap parts there are plenty of other more likely reasons including focus on cost vs. reliability, poor quality sourcing, vendors subbing lower quality parts, etc. etc.

You also seem prone to generalizations based on limited data. Do some car amplifiers have crap caps in them? Sure, more than likely. Does that mean it's universally the case? No, not at all.

I suppose to some extent I am also guilty of both with my comment above on low profile caps... but, at least it was an opinion based on a lot of different examples I've encountered of those failures over decades of exposure. There's a whole generation of Toyota OEM car radios that loses audio due to one of those caps leaking and eroding the mute control trace so badly it goes open circuit, as another example. You can pretty much count on that happening to every one of those radios, over time.

However, I am sure there are lots of examples of more normal profile caps leaking and no real statistics to back it up one way or another. Still, when you see a particular design over and and over again and the other normal caps - even the ones in the "runs hot" power supply don't physically leak over 20-30 years but a high percentage of the low profile ones do, it does beg the question.

John

you seem prone to misunderstanding people

if i were jumping to conclusions, why would i be asking questions?

rockford fosgate is a bit higher end of the spectrum when i comes to car amplifiers, so to see some crappy filter caps being used when all the others are good nichicon only leads me to believe they skimped out on filter caps and put a sticker on the amp saying tampering voids the warranty

 

[yotems]

i think this thread will help people that dont already know it come to realize why we live in an electronic golden age for caps

 

[Oilmaster]

vishay is also Philips .

Well, more precise:

BC bought the capacitor division from Philips when Philips sold off all component manufacturing activities, like the former Philips semiconductor division was spun off as NXP, giving cause to the local joke New-Ex-Philips here in Holland.

BC maintained the Philips capacitor coding system, and the transparent blue casing colors.

Then Vishay bought BC completely, and in most cases labelled from there Vishay BC. The transparent blue casing color gradually moved to opaque lighter blue.
Some original Philips capacitor type codes are still maintained under the current Vishay flag.

In this business, you can make family trees

 

[onwardjames]

I'd like to say I understand all this, but I'd be lying, big time.

To the OP, you have managed to keep things civil and get your point across. Congrats on using the internet for learning (cummins dodge motors?? Damn!) and for that I applaud you.

Most just use it for titties and texts, to tell the truth.

This is a fantastic thread. Keep the good info going, everyone.

 

[Freds.Bands]

Electrolytic caps are now much smaller because of the greatly improved anode etching methods. That larger surface ares means greater capacitance per cubic centimeter. Another thing: low ESR caps are those with high water content in the electrolyte, invented in Japan by Rubycon, but water without proper stabilizers eats away at the aluminum electrodes, causing those to fail with short life spans; unless those low ESR caps have the proper chemical stabilizers (among the hundreds of formulas), they will fail while in short service. This what happened in the early 2000s to those failed computer motherboards with certain Taiwanese low ESR caps. (ConradH is once again right on the money.)

I just finished summarizing the two major wikipedia articles on electrolytics (eliminating the chemistry and math).The above is just a sample of what is in the article.

I would post the long article on AK, but I do not know in what area to post it/them.

 

[jdurbin1]

There are no questions in the post I responded to (http://audiokarma.org/forums/index....n-their-day-vs-new.702514/page-5#post-9430226), just a questionable conclusion, which you then repeat here.

I'm all for education but where does that fit in with learning? As I recall, one of the important parts is learning early on just how much we *don't* know and with that knowledge in hand, focusing on listening to and learning from others that do know instead of spouting unfounded opinions while still in the act of trying to grasp the basics.

I'm quite sure the "crappy filter caps" were used instead of "good nichicon" (some more presumptive statements) because there was no suitable Nichicon part for the application or because the part selected was more suitable (despite your opinion), not because Rockford Fosgate is profiting by selling amps with a few poor quality parts sprinkled around inside so they can rake in the repair money. Call me skeptical on that one... based on having met a number of of the folks behind that particular brand during the roughly 35 years I've spent working in the same industry - including the founder Jim Fosgate BTW.

John

you seem prone to misunderstanding people

if i were jumping to conclusions, why would i be asking questions?

rockford fosgate is a bit higher end of the spectrum when i comes to car amplifiers, so to see some crappy filter caps being used when all the others are good nichicon only leads me to believe they skimped out on filter caps and put a sticker on the amp saying tampering voids the warranty

 

[yotems]

There are no questions in the post I responded to (http://audiokarma.org/forums/index....n-their-day-vs-new.702514/page-5#post-9430226), just a questionable conclusion, which you then repeat here.

I'm all for education but where does that fit in with learning? As I recall, one of the important parts is learning early on just how much we *don't* know and with that knowledge in hand, focusing on listening to and learning from others that do know instead of spouting unfounded opinions while still in the act of trying to grasp the basics.

I'm quite sure the "crappy filter caps" were used instead of "good nichicon" (some more presumptive statements) because there was no suitable Nichicon part for the application or because the part selected was more suitable (despite your opinion), not because Rockford Fosgate is profiting by selling amps with a few poor quality parts sprinkled around inside so they can rake in the repair money. Call me skeptical on that one... based on having met a number of of the folks behind that particular brand during the roughly 35 years I've spent working in the same industry - including the founder Jim Fosgate BTW.

John

well explain that to the crap filter caps then. they dont care for your explanation because nichicon has the exact cap in the same size

all the nichicon caps in the unit are fine

every cheap filter cap is bad

im gonna disregard things you say

 

[jdurbin1]

I should be offended by that but somehow it just made my day.

Good luck with your ongoing education.

John

 

[Oilmaster]

I should be offended by that but somehow it just made my day.

Good luck with your ongoing education.

John

+1

John,
You just made my best day since many years while reading your (educated) line:

" I'm all for education but where does that fit in with learning? As I recall, one of the important parts is learning early on just how much we *don't* know and with that knowledge in hand, focusing on listening to and learning from others that do know instead of spouting unfounded opinions while still in the act of trying to grasp the basics."

Let's not waste our time with mechanical dudes who simply can't understand what you wrote in the first place.

 

[yotems]

+1

John,
You just made my best day since many years while reading your (educated) line:

" I'm all for education but where does that fit in with learning? As I recall, one of the important parts is learning early on just how much we *don't* know and with that knowledge in hand, focusing on listening to and learning from others that do know instead of spouting unfounded opinions while still in the act of trying to grasp the basics."

Let's not waste our time with mechanical dudes who simply can't understand what you wrote in the first place.

whats there not to understand? dudes wrong plain and simple. just because he doesnt think rockford fosgate would put cheap filter caps in a 550 watt amplifier doesnt mean they wouldnt.

filter caps going bad is a lot cheaper than transistors burning up boards or even a fire

cheap filter caps might be the preventative measure keeping people from really messing it up, specifically the people who are going to run it bridged for 550 watts and clip the **** out of it in the trunk of a fuel efficient japanese wannabe race car like this one was

theres just no getting around the fact that the generic filter caps are the only thing thats bad

 

[SoundOfSound]

If I'm understanding your last post correctly?

Capacitors are not used to protect circuits. There are an array of other things like fuses, fusible resistors and protection relays that do that job.

If the caps have a short life span then they not are being used correctly and may be of the wrong type.

Putting general purpose caps in a switching power supply is a big no! no! as well as not keeping the proper voltage headroom rating to accommodate voltage surges and spikes.

Then there is the issue of heat. If the electrolyte is running hot the cap will have premature failure.

I would consider an automobile to be an extreme environment for capacitors with all the vibration and extreme temperature changes.

 

[yotems]

If I'm understanding your last post correctly?

Capacitors are not used to protect circuits. There are an array of other things like fuses, fusible resistors and protection relays that do that job.

If the caps have a short life span then they not are being used correctly and may be of the wrong type.

Putting general purpose caps in a switching power supply is a big no! no! as well as not keeping the proper voltage headroom rating to accommodate voltage surges and spikes.

Then there is the issue of heat. If the electrolyte is running hot the cap will have premature failure.

I would consider an automobile to be an extreme environment for capacitors with all the vibration and extreme temperature changes.

well the protection circuitry trips when the filter caps go bad, and i dont think there are any fuses on or in that amp. just checked and none outside, i dont recall there being any inside either but maybe there is in between the trace side of the board and the heat sink/ housing

im not trying to say capacitors are used as fuses because they arent, but i could see a way where failed filter caps are a much cheaper fix than anything else that abuse leads to and i could see where a manufacturer would rather it be the quickest possible turnaround

 

[SoundOfSound]

There could be some fusible resisters in there. They look just like regular resistors so you would have to look at the service manual to be sure.

Protection relays are typically set up to monitor a voltage. If the voltage is out of range then they trip.

Are these bad caps in a SMPS? ...they have a tough life.

 

[gslikker]

I have a defective easy looking but quite complex Micromega amp having no schematic to be found. It has some very smart electronic protection. I it even checks the four fuses of the plus and minus main power rails where the smoothing caps are.

It is on the pile of unsolved mysteries since transistors are packed together.
I would have to take it totally apart and draw the schematic myself from what I see, so I guess take a month to repair.
Guess it will be on the pile until my retirement and by then it is real vintage...

I would be very glad if the problem moves itself to the power smoothing caps, would be an easy fix, which this topic is about.

Unfortunately, amp manufacturers can not make failing amps move the defectiveness to specific components beforehand, and the Nichicon name on it does not prevent caps from failing.

 

[Blue Shadow]

I'd like to say I understand all this, but I'd be lying, big time.

To the OP, you have managed to keep things civil and get your point across. Congrats on using the internet for learning (cummins dodge motors?? Damn!) and for that I applaud you.

Seems the OP has jumped the shark and is dissing one of our respecteds. He probably earned an ignore for that.

Curious if he has done his homework on that cap that he claims is a repair payment waiting to happen and if Nichicon made the same size cap at the time when the amp was built. His attack shows his newbness but what the heck. He'll learn.