Sansui big capacitor replacement - disappointment

[EchoWars]

My input to this thread has basically gone nowhere, so first consideration for any additional post of mine here will be its brevity (i.e., I'm not hip on wasting a lot more of my time trying to convince those who's mind is already made up).

 

[Kjell-B]

The fact is the output circuit is a simple circuit to anyone with a knowledge of basic electronics. The designers of these units did not listen to "magic parts" they bought parts that fit a design specification and a cost to keep the unit competitive and profitable and affordable. If they could have used the better performing parts of today they would have.

In my opinion audio quality has little to do with the price of electronic parts (at the time in question). I have been listening carefully to expensive modern high end capacitors, resistors and so on, and there is little if any advantage from using expensive modern components. Especially modern polypropylene capacitors often sound terrible.

The main problem in audio occurred around the year 1980, where there was a huge shift in materials and construction of electronic parts (to reduce costs) - in connection with the large scale manufacture of computers. Thus electronic parts became computer parts. While earlier (cheap as well as expensive) electronics were audio and radio.

Todays expensive electronic parts are manufactured under more strict tolerances and control; this has nothing to do with their audio properties, most modern high end parts and components are still computer components since they are produced using the same modern methods and principles as cheap modern components.

So yes, the manufacturers of hifi always chose quite cheap parts, but after 1980 cheap parts became computer parts, and this is very easy to hear.

Electronic parts/components after 1980 are manufactured using much cheaper production methods than earlier. So cheap parts became even cheaper.

 

[Morden2004]

My input to this thread has basically gone nowhere, so first consideration for any additional post of mine here will be its brevity (i.e., I'm not hip on wasting a lot more of my time trying to convince those who's mind is already made up).

Hardly gone 'nowhere', EW. :scratch2: You speak for many of us who are not technically challenged and educate the many who are and are looking for answers. Anyone who has spent more than 1 week on this site knows where the 'restoration intelligence' is; you and several others are the source of our knowledge.

That said, it doesn't mean that others don't know squat but in any technical discussion where the subjective merits of the issue are being debated there will always be a division of view points.

So, with that in mind and with a lot of fodder to pour through, I'm going to declare this thread finished. I'm not closing it (yet) but I think we've said it all.

Do you agree?

Paul

 

[EchoWars]

Well, I hope I didn't sound TOO negative, but I simply feel I've been banging my head against a wall trying to make what is essentially three very simple points:

1. Electrolytic capacitors have a definite lifespan, and old caps contribute to numerous sonic issues, intermittent problems, and outright failure of vintage audio gear.

2. New electrolytic capacitors (properly chosen for the job at hand) are vastly superior to those used by manufacturers in the past in every measurable way, including empirically (listening).

3. I see reinforcement of these first two points on a daily basis, and have yet to discover evidence to contradict them. Others who have both been doing audio repair since Kennedy was President, and have made substantial names for themselves in the audio design field concur with my observations and conclusions.

Pretty much sums it up for me.

 

[Kjell-B]

Well, I hope I didn't sound TOO negative, but I simply feel I've been banging my head against a wall trying to make what is essentially three very simple points:

1. Electrolytic capacitors have a definite lifespan, and old caps contribute to numerous sonic issues, intermittent problems, and outright failure of vintage audio gear.

2. New electrolytic capacitors (properly chosen for the job at hand) are vastly superior to those used by manufacturers in the past in every measurable way, including empirically (listening).

3. I see reinforcement of these first two points on a daily basis, and have yet to discover evidence to contradict them. Others who have both been doing audio repair since Kennedy was President, and have made substantial names for themselves in the audio design field concur with my observations and conclusions.

Pretty much sums it up for me.

1. Probably true, but this life span may vary from 5 years to maybe 500 years or more. Very much dependent on brand and production date. And of course in what circuit the capacitor is installed (as discussed in detail earlier).

2. Not proven true, since a) the determination of life span requires some years to come, and b) our experience so far has shown that there are periods of good quality later followed by periods of low quality. While low ESR caps may be the right thing for large power amps, listening tests may reveal different conclusions for other vintage circuits.

3. A statement like this requires systematic investigation of equipment from 1950 and to today and of equipment from all major manufacturers (USA, Europe, Japan, others).

I believe a service technician mostly see equipment selected for failures (a natural selection so to speak), and opinions (incl. on frequency of failures) may be colored by this selection. Also, there may be more serious specific considerations re. large power amps.

When I use my knowledge (in part published here) to pick the right quality equipment, I can have all periods covered by equipment that does not require any new capacitors.

 

[dnewma04]

Glen/Rich (and others),
Thanks to all of you for being the voice of the rest of us without the time/energy/motivation to join this thread. Luckily, there are only a couple of people you can't get through to, for the rest of us, you are coming through loud and clear. Objectively, new electrolytics are obviously superior. Subjectively.... well, who cares what others subjective opinions are, if I did I'd probably have an awful system with no clear system direction.

 

[Donkey!]

Ahhh you say tomato, I say motor oil. :scratch2:

Just be happy all of your "Vintage" gear doesn't require the use of a flux capacitor.

Because when those fail, whooooa molly.

 

[nosirrah]

this thread

Thanks to all that took the time to reply with their opinions and knowledge to this thread, I learned somethings I did not know, and read some differing opinions about the subject.
Those opinions did not sway me from my original thoughts on cap replacements, but did supply food for thought.
My sets will get new caps as needed, and when in doubt I will change them.
A diverse group here on AK, it's good to have these debates, even when they get heated and off topic a bit.
Casey:yes:

 

[targeteye]

Rich,
Thank you for taking the 2 to 3 hours for your reply. It certianly cleared up a lot for me.

Just curious. How do you go about compensating the servo circuit for new "faster" outputs?

I bit off topic and perhaps a new thread would be more appropriate?

Steve

 

[LBPete]

1. Probably true, but this life span may vary from 5 years to maybe 500 years or more. Very much dependent on brand and production date. And of course in what circuit the capacitor is installed (as discussed in detail earlier).

2. Not proven true, since a) the determination of life span requires some years to come, and b) our experience so far has shown that there are periods of good quality later followed by periods of low quality. While low ESR caps may be the right thing for large power amps, listening tests may reveal different conclusions for other vintage circuits.

3. A statement like this requires systematic investigation of equipment from 1950 and to today and of equipment from all major manufacturers (USA, Europe, Japan, others).

I believe a service technician mostly see equipment selected for failures (a natural selection so to speak), and opinions (incl. on frequency of failures) may be colored by this selection. Also, there may be more serious specific considerations re. large power amps.

When I use my knowledge (in part published here) to pick the right quality equipment, I can have all periods covered by equipment that does not require any new capacitors.

Kjell-B, You clearly have well-established beliefs on this topic and have made a range of very general statements about your observations. These opinions are in fairly direct conflict with the professional opinions of several of our members that have years of professional training and experience under their belts. These folks have a lot of credibility here.

Can you give us a picture of your background to support your opinions? Do you have specific scientific or technical training and experience? Have you worked in the electronics industry? What makes you say that since 1980 capacitors are for computers and not audio?

- Pete

 

[MarkMeyer]

The main problem in audio occurred around the year 1980, where there was a huge shift in materials and construction of electronic parts (to reduce costs) - in connection with the large scale manufacture of computers. Thus electronic parts became computer parts. While earlier (cheap as well as expensive) electronics were audio and radio.

Todays expensive electronic parts are manufactured under more strict tolerances and control; this has nothing to do with their audio properties, most modern high end parts and components are still computer components since they are produced using the same modern methods and principles as cheap modern components.

If you are to assume that all modern capacitors are computer parts, then where does that put a cap like the Elna Silmics ( http://www.audio-cube.nl/elna.htm ) ?
Is their being touted as "audio" capacitors just a bunch of hooey?...

EW, on the other hand, has an opinion that even cheap caps can be used if properly chosen which I assume means using "computer" capacitors.
Should we or should we not expect a difference in sound for the most part between using the "audio" Elna caps or just finding something that has the right basic specs of "any 'ol kind"?

I'm not trying to promote an argument; just trying to get this in my head to where it can do me some good.
For the moment, I think I'm with EW and I am skeptical that an individual cap will make anywhere near the difference as would the basic design of the amp itself.

 

[Morden2004]

Open a new thread

Start a new thread if you want to discuss more about personal reasons and experiences on the subject of electrolytics and their lifespan. This will better serve the subject and not add more repetitive matter to this already excellent thread.

I feel we've covered the subject nicely here and we can exit this thread all still friends :thmbsp: -- and, I for one, have learned quite a lot from the discussion. I have modified my stand on the subject of electrolytics thanks to several members on opposite sides of the discussion. And I think that says a lot about the learning process here on AK.

Thanks to all. A job well done! :yes:

Paul

 

[Morden2004]

Well, I hope I didn't sound TOO negative, but I simply feel I've been banging my head against a wall trying to make what is essentially three very simple points:

1. Electrolytic capacitors have a definite lifespan, and old caps contribute to numerous sonic issues, intermittent problems, and outright failure of vintage audio gear.

2. New electrolytic capacitors (properly chosen for the job at hand) are vastly superior to those used by manufacturers in the past in every measurable way, including empirically (listening).

3. I see reinforcement of these first two points on a daily basis, and have yet to discover evidence to contradict them. Others who have both been doing audio repair since Kennedy was President, and have made substantial names for themselves in the audio design field concur with my observations and conclusions.

Pretty much sums it up for me.

No, Glenn, you didn't come off as too negative - perhaps too passionate about the subject, but that's allowed :thmbsp: here. We can't learn if we don't have qualitative input from the members who do the work. It was a good discussion.

Paul

 

[Kjell-B]

Kjell-B, You clearly have well-established beliefs on this topic and have made a range of very general statements about your observations. These opinions are in fairly direct conflict with the professional opinions of several of our members that have years of professional training and experience under their belts. These folks have a lot of credibility here.

Can you give us a picture of your background to support your opinions? Do you have specific scientific or technical training and experience? Have you worked in the electronics industry? What makes you say that since 1980 capacitors are for computers and not audio?

- Pete

Thank you for an important question.

If you are an engineer you should know the answers. Engineers should with their background be interested to elucidate the "catastrophy" that occurred around 1980. The event is well known among musicians, modern studio engineers and older hifi friends that have been on the long hifi road.

And if you know the history of electronics you should know about the growth of computer industry from 1980 on, that may explain the change from audio-friendly components to cheap computer components.

I am not an engineer, but have some scientific background including physics.

I could write a long essay around this topic, I have collected quite some information which is easily available for engineers. But since this information is easily available on the internet (newer production) or older radio books, it is your choice. If you want to continue along the spec's road as most engineers do, there is nothing I can do to change that.

I can however give one simple example: Resistors in hifi equipment were carbon film (a rather thick carbon layer) up to 1980, later all manufacturers changed to metal film resistors. There are carbon film available today, but they are very different from the old ones and resemble and sound like metal film.

Capacitors: almost everything is different - type of electrolyte, insulation materials, and so on. I think some safety aspects also were considered.

There are many engineers posting information on the internet. Why don't they write about these topics ? Well, a very few do.

 

[QuadBob]

Electrolytic capacitor design and construction

After catching up on the ongoing discussion here, it seems apparent that some (Kjell-B) still want to deny the science and reality of electrolytic capacitor construction. So, my planned post on "subjective" evaluations and experience after "totally" re-capping over 300 audio units will have to wait.

I would refer any new readers to my first fact post #61 and to Morden2004's post #101 especially noting his attachment which shows the physical construction of an electrolytic capacitor.

Now if you have read those..........then the following will make sense:

Electrolytic capacitors when used in power supply (both High and Low voltage) are virtually identical to your car battery. They include a charged plate, and ELECTROLYTE in either a liquid or paste formula.

So let me pose the first question regarding their construction:

"Why does Nichicon rate their life expectency at 15 years MAXIMUM and shorter depending on use and ambient temperature"?

The answer is found in Morden2004's post #101 attachment. It is primarily because of two reasons:

1) The capacitor contains electrolyte in either a liquid or paste form! Over time the electrolyte will EVAPORATE!! This evaporation process while varying slightly in the time it takes to occur.......HAPPENS irregardless of whether the unit it is installed in operates daily or is simply in storage.

ESR and its change in a specific cap is dependent on the conductivity of the electrolyte. When "new" and the electrolyte is still in a liquid or paste form........it is low. This is easy to understand as you can just think of it as passing an electric charge through water or any liquid. Once the electrolyte has evaporated...........you are now trying to pass an electrical charge through what is really more like "concrete" than liquid.

2) The only way to prevent evaporation is to SEAL the cap...........which again referring to the construction of electrolytic capacitors you will find that they all MUST include a "VENT". Why? Very simply because depending on the AMBIENT temperature and the electrical charge passing through them......... they give off gas and expand/contract depending on temperature. If they were sealed.......they could explode or bulge when expanding. Their vent allows them to expand/contract as needed to maintain stability.

So from the above we can add a new FACT to this thread:

FACT: All electrolytic capacitors are subject to evaporation of their electrolyte whether in use or in storage.

The only possible question to this is "How long does it take for the electrolyte to evaporate enough to affect performance"? And the answer is found right in Nichicon's chart:

FACT: The MAXIMUM storage life is 15 years even if the unit has NEVER been turned on.

Anyone that wants to deny or ignore these facts does so at their own risk (and unfortunately the risk of their equipment!!) But, this isn't rocket science gentlemen.........

Based upon the above it can also be easily determined that if someone says they prefer the "original" sound as designed by the Manufaturer they also have to recognize that:

1) The original design utilized "new" caps with liquid or paste electrolyte present in every electrolytic cap. So, if TODAY you wanted a true experiment as to what a specific piece sounded like....all you have to do is:

A) Find a "new in the box" never used piece.
B) Totally "re-cap" it and replace every electrolytic capacitor in it.


In looking on the internet for scientific examination of electrolytic capacitors I found the following analysis which is directly on point for our discussion here:

Having found that Nuclear Safety Related units had the capacitors installed IRI issued a verbal notification of the 10 CFR 21 report on January 22, 1999 at 1420 CST and was issued and incident number of 35,304. IRI also verbally notified Mr. M. Reno (NYPA) and W. Brian Barrett (NIMO) of the 10 CFR 21 report and the models and serial numbers of the units that the capacitors were insulted in.

Attachment 2, is the complete list (Nuclear Safety Related and Non-Nuclear Safety Related)of all units identified during the IRI records search that contain the 9322H date coded capacitors. IRI will transmit this list to each of the affected utilities, with this report, for all of the affected modules.

Failure analysis of the capacitors at BMI found that "...all of the parts were very dried out, and there was basically no electrolyte left. The seal bead dimension on all five parts measured 0.225". This is slightly larger than the current specification of 0.205 +/-0.008. Four of the five capacitors anode wire was broken internally, but it could not be determined what caused this failure. However, the fifth capacitor was not severed, but was still dried out. This is why we feel the root problem of the failures was the drying out of the capacitors."
(See Attachment 1 for the full letter from BMI).

CONCLUSION AND RECOMMENDATIONS

IRI has concluded that the Sprague model TE1302 capacitors with a date code of 9322H were manufactured with an end seat bead that was larger than specifications currently allow, the end seal allowed the capacitor's electrolyte to dry out (offgas) in an accelerated manner, causing the capacitors to fail in an accelerated manner. The failure mechanism of the capacitors are in the normal manner of all aluminum electrolytic capacitors, drying of the electrolyte which results in increasing equivalent series resistance (ESR) leading to increased heating of the electrolyte, leading to increased electrolyte drying, leading to increasing ESR, until the electrolyte is totally dried out and the capacitor fails.

IRI recommends that these capacitors be replaced as soon as practical. Since these capacitors have served over 60% of the expected shelf/useful life of the aluminum electrolytic capacitors IRI recommends that the modules that they are installed in be totally refurbished and all aluminum electrolytic capacitors in the modules replaced, during replacement of the affected capacitors.

You can subjectively debate different capacitor brands and their subjective sound quality..........but to try and debate the above information or claim that electrolytic capacitors can last for "500" years.........is a simple denial of reality. And, that too is a FACT.

QB

ps: Paul this thread really should be a sticky. At least those posts regarding electrolytic capacitor theory, construction and operation in "vintage" audio equipment. And, please don't close it yet.......I hope to have a statement regarding audio signal path caps and what they do to audio signals later this weekend.

 

[Kjell-B]

After catching up on the ongoing discussion here, it seems apparent that some (Kjell-B) still want to deny the science and reality of electrolytic capacitor construction. So, my planned post on "subjective" evaluations and experience after "totally" re-capping over 300 audio units will have to wait.

I am sorry, but with my own (maybe limited) scientific background I have not been able to see much scientific proof here.

However, a fews facts that are not directly related to (subjective) audio quality have been presented - something like capacitance, ESR and leakage current. These are some main specifications, but there are probably 100 more spec's to be elucidated and explained, before perceived analog audio can be described in strict objectice physical terms.

Until then our ears must guide us.

I am not here to prove anything. But I have tried to systemize my observations and hifi experiments through a long hifi life in order to have a fruitful communication with other hifi and music enthusiasts. I feel it has been possbile to have the concert hall in my living room for many years. But not by the help of spec-oriented engineers.

 

[QuadBob]

Kjell-B, I really hope you can understand that my point in this discussion really isn't to argue with you. It is simply to make sure that all of us are AWARE of the facts in dealing with vintage audio components. Early on in your posts here you were skeptical........and as I previously noted there is nothing wrong with that. I like to think that most of us professional engineers ARE skeptical as well! But, you are now simply proving that "ignorance is bliss".

I've yet to find in ANY of your posts any links or "scientific proof" to your totally subjective opinions. Nor have I seen you cite any personal experience with an open minded subjective evaluation of units that are totally restored vs. unrestored units, which some of us here most notably myself and EchoWars have daily experience with.

I actually agree with some of your opinions which will become clear when I can finish my "sound quality" post regarding electrolytic capacitors. But, this latest post of yours really demonstrates that you seem to be incapable of seeing objective facts as such:

I am sorry, but with my own (maybe limited) scientific background I have not been able to see much scientific proof here.

Like these:

Electrolyte = Liquid
Liquid = evaporation

Electrical conductivity through a liquid is VERY different than through non-liquid materials.

However, a fews facts that are not directly related to (subjective) audio quality have been presented - something like capacitance, ESR and leakage current. These are some main specifications, but there are probably 100 more spec's to be elucidated and explained, before perceived analog audio can be described in strict objectice physical terms.

Capacitance, ESR and leakage current ARE DIRECTLY AND OBJECTIVELY RELATED TO AUDIO QUALITY!!!

Until then our ears must guide us.

True........but the ability to utilize and reason with what lies between our ears is of paramount concern. Our perceptions are colored by that ability, just as you have chosen to utilize a "new amplifier" and high quality speakers to discern the sometimes subtle differences in audio quality presented by "vintage" preamps. Many others of us have chosen "vintage" amplifiers and speakers as well both for their construction and sound quality.

I am not here to prove anything. But I have tried to systemize my observations and hifi experiments through a long hifi life in order to have a fruitful communication with other hifi and music enthusiasts. I feel it has been possbile to have the concert hall in my living room for many years. But not by the help of spec-oriented engineers.

Well I don't know whether to take your "spec-oriented engineers" comment as a compliment or insult!:scratch2: While I DO have a degree in electronic engineering my pursuit and enjoyment of vintage Sansui audio predates my degrees and for those like myself.....it is the sound quality of Sansui equipment AND the music I listen to that makes any of this matter!:thmbsp:

Enjoy!

QB

 

[Kjell-B]

1. Early on in your posts here you were skeptical........and as I previously noted there is nothing wrong with that. I like to think that most of us professional engineers ARE skeptical as well! But, you are now simply proving that "ignorance is bliss".

2. Like these:

Electrolyte = Liquid
Liquid = evaporation

Electrical conductivity through a liquid is VERY different than through non-liquid materials.


3. Capacitance, ESR and leakage current ARE DIRECTLY AND OBJECTIVELY RELATED TO AUDIO QUALITY!!!

1. Well you brought in the word ignorance here.

Discussions like this is just repeated statements and no scientific proof. Thus also a kind of ignorance.


2. I extend your logic a little:

Electrolyte = Liquid
Liquid = evaporation ????
Liquid = no evaporation if tight container.


3. Yes of course. No one has objected to that. But there are probably 100 other spec's in a capacitor that contributes to audio quality. Thus, for practical reasons, listening tests proves crucial.

 

[Morden2004]

We can continue the discussion ...

OK, Bob, we'll keep it open as long as we are having a constuctive discussion. Kjell-G and others have an opposing opinion on the merits of replacing electrolytics and, I must confess, I was biased towards the "if it ain't broke ... " camp but you, Glenn and others have moved my butt over into the "should be replaced if over 10-15 years old" camp.

I think that Kjell-G and a few others are having a difficult time separating the science of these devices and the sound quality that a vinatge unit exhibits in state "A" vs. state "B"; A=original caps and B=replaced with modern caps.

The problem with that argument, in my opinion, is that the quality of sound is virtually 100% subjective and often is judged without the necessary sicentific controls in place to filter out subjective opinions.

Anyway, gentlemen, continue with the discussion and educattion. This may become the best thought out thread we've ever had. :thmbsp:

Paul

 

[LBPete]

Thank you for an important question.

If you are an engineer you should know the answers. Engineers should with their background be interested to elucidate the "catastrophy" that occurred around 1980. The event is well known among musicians, modern studio engineers and older hifi friends that have been on the long hifi road.

And if you know the history of electronics you should know about the growth of computer industry from 1980 on, that may explain the change from audio-friendly components to cheap computer components.

I am not an engineer, but have some scientific background including physics.

I could write a long essay around this topic, I have collected quite some information which is easily available for engineers. But since this information is easily available on the internet (newer production) or older radio books, it is your choice. If you want to continue along the spec's road as most engineers do, there is nothing I can do to change that.

I can however give one simple example: Resistors in hifi equipment were carbon film (a rather thick carbon layer) up to 1980, later all manufacturers changed to metal film resistors. There are carbon film available today, but they are very different from the old ones and resemble and sound like metal film.

Capacitors: almost everything is different - type of electrolyte, insulation materials, and so on. I think some safety aspects also were considered.

There are many engineers posting information on the internet. Why don't they write about these topics ? Well, a very few do.

Krell, this is somewhat of a dodge of my question about your background. But if you would like to go down this road, can you post some links to point us to the information that supports your position? I would be very interested in learning about the "catastrophy" you are referencing but I'm not an engineer so I'm having trouble finding it.

The only audio "catastrophy" that I'm aware of arround 1980 was the rising value of the Japanese yen and the saturation of the audio market that resulted in the end of the golden era of Japanese audio.

- Pete