When recapping a receiver or amplifier, quite often the unit will sound like crap until the capacitors form and settle in to their happy place. It take up to a couple of weeks for the caps to settle in. The amp won't sound it's best until this happens. That's from my experiences and not something I read on the internet
Possibly. The one I did the guy did listen to it for several days though. It wasn't that he came back the same day as i tried to defuse him as i didn't want it back. He paid me only 30.00 to put it back and that was considerably less than I charged to do the initial work.
Most bad capacitors I've seen have been in gear from late nineties early 00's, when China started stealing and badly replicating cap recipes. Ancient Elna and Rubycon caps almost always measure ok!
Thanks for this video Dave 👍🏻🙂. Appreciate the explanation on recapping. I’ve done just that on some 90’s gear which didn’t help me resolve a problem and it was frustrating to say the least. I’ll focus more on what else can cause issues.
Capacitors cause specific problems. Yes doing a total recap will fix a problem if it is caused by a capacitor. Troubleshooting and replacing that one cap will also fix it. It won't fix a problem caused by a bad transistor, diide6, resistor, diode, inductors, crystals, or solder connections.
funny thing , i ve did lots of solder joints on a cassette deck logic board , and it became TOTTALY unresponsive , almost like it was dead. Cleaned the flux with flux cleaner , problem gone. Wierdest thing that i ve encountered , ever.
33:36 capacitors and people, it's a mental condition, I'm convinced, and good for you for pointing that out - knee jerk reaction = caps! There is a lot more as you rightly point out. Preamps, etc I've noticed no significant improvement with swapping caps - older power amps? sure - swapping low value elec with film in signal, usually a good thing if you have the patience to cross reference and purchase.
Actually it was about a week before he returned whining about it and was back and forth a few times before i agreed to changing them back and only after he paid me up front so he wouldn't screw me over for the rework.
Hmm quality sewage 😀 I have never been a mass capacitor replacer, only the ones that look or read bad. If a known failure then replace it. Where people got the idea of mass capping i don't know. That daft owner that demanded a mass re-capping is a Asshole (Technical Description). Your cat just wants a little attention, it seems like a happy pet. Some cats are only Fuss and Food, then they piss off lol.
But I think is laughable is there are some certain high-end amplifier manufacturers that will recommend full cap replacement after 10 years. Of course this is just a money maker for their dealer Network if the manufacturer suggests that this has to be done some people will be silly enough to spend $1,000 and I'm sure that these boutique manufacturers would be charging that much for their repair kit, to do it. Although modern ones they probably are shot in 10 years because the environmentally friendly ingredients and construction of new caps a tend to not last anywhere near as long as the old ones wishes that really bad chemicals. As to the cat paid me a visit she was probably trying to tell me that she was hungry. That's typically the only time I see them when they want something other than that you're right they're off sleeping somewhere. I try to keep them out of the shop as much as possible because there are a lot of hazards in here. Dirt bits and pieces from equipment being worked on ends up on the floor and they like to roll around on the ground because it's nice and cool and they get all that crap on their fur and then go and lick it and could ingest something that could make them sick so I generally try to keep them out of the workshop. Little bit of snipped off wire for example could be fatal if they were to swallow it.
Most likely from caps' manufacturers listing 15 years as the guaranteed lifetime of the rubber seal in pretty much every data sheet I came across. For many, that's enough of an incentive, even slightly elevated ESR and somewhat leakage, might be another.
@@paulb4661 they actually used to rate them in hours depending on what they were designed for. As low as 8,000 hours for some and others as high as 60,000 hours. I have a sharp LCD monitor that's used for my security cameras and it's left running 24/7. Last time I checked it it was sitting at 68,000 hours and still going strong. The new modern capacitors are not designed to last anywhere near as long as the older ones were and a lot of it has got to do with the chemicals that are in them. The newer ones I rated at a much lower lifetime because of how they're constructed much lighter materials and smaller physical size. This increases the likelihood that rubber seals are going to fail a lot sooner on newer than older capacitors.
@@12voltvidsThe rubber seal quandary is all but a single sentence, hidden amongst other superfluous data. It has to do with allowing for thermal expansion, whilst keeping electrolyte escape levels to the very minimum at the same time. Many, many well made caps will happily get past the goal post and continue to perform well into their pension, especially if reasonably sized and not stressed to the limit during their lifetime. Many modern miniatures, especially those manufactured to the highest standard in a certain Far Eastern country, will fail, often spectacularly before they even get going. With antique, prized posessions, re-cap by all means with whatever you can squeeze in there. They dont make them like they used to and it only takes one leak to possibly send some of unobtainable ICs to Valhalla. With more modern, high quality equipment, where lower tiers caps found a home, I wouldn't hesitate either. Had 50 year olds indistinguishable from brand new, similarly sized equivalents, but also had many dried out and acting partly as resistors. Had some leaking, both colloquially and literally speaking, but also had some in their teens, half dead, with burst seams 🤦♂️
@@12voltvids Yep cats = FF Food and Fuss. They are selfish little gits but we like pets. I liked dogs better as they are always happy to see you and never judge you. But they can be as thick as sh-it. Dogs need walking and for some people it's an excuse to wander around with no set destination.
Can you please stop leaving HDMI and kettle leads hanging over your screen please? I watch you on a large screen TV and they look life size on my screen! I keep thinking 'who left a lead hanging over my TV ', it's confusing. Larry
I'll guess. Transistor. But I'll watch to see if I'm right or wrong. Edit: not exactly. Btw, soldering to me is a skill I have trouble mastering. I guess I need more practice. Those ladies must have been very good.
To start with, you are my electron sensei. I have been an auto and boat wrench all my life, specializing in electronics installation and integration. With the help of your 12volt vids I was able to get my NAD 7155 working. My NAD 2200 is a different story. Not sure what I did but it likes to make smoke now. I noticed one transistor had a solder joint that looked like the loose one you found. I pulled it and checked it with my ohm meter, seemed ok, put it back in and presto more smoked resistors, about 4 of them . This is an adventure and I love it. Thank you and and keep the great info coming!!
Can low temperature solder help prevent the pads or traces from lifting? Pros and Cons transistor heat can cause the solder to melt and cold solder joint.
Not really. Low temperature solder has its own problems all you have to do is look at all those RCA TVs made in the 1990s with the integrated tuner and how many problems they had same with Sony with in the 80s and '90s all the problems in their tuner modules that were all put together with low temperature solder.
I concur, I ran a repair shop for 35 years, in all that time I never did a full capacitor replacement on any amps that I repaired, it was completely unnecessary.
It's a money maker for shops these days. Just like the crook at the local tire shop. Took my old truck in there about 4 years ago to get the driver side half shaft replaced because it was clunking. Once "Andy" got it in the shop the estimate of 600 jumped to 1300 because he said it needed both and he was unable to just change one because the other was worn and used a bullshit unsafe vehicle claim to say he couldn't and wouldn't just replace the single bad part. Held me hostage. I was selling it and didn't want it making noise for the new buyer. Did i care if the other one wore out next year? No, it had 185,000km on it. So i put 1300 into a vehicle that ultimately i sold for 1000 because the crook on the corner held my truck hostage. His name isn't Andy by the we at but it rhymes with it. Any local reading this will know exactly who i am talking about. sucks to be home because i tell everyone about it and I have not been back there for tires since. That tactic lost him a customer (me) that he had for over 20 years. Do what your customers ask and nothing more. Padding your bottom line and taking customers for a ride is a good way to loose smart customers. Dumb ones that believe the bullshit well they deserve to get taken for a ride.
Long before the change all the caps thing came about, when I got a repair in would troubleshoot and repair the problem. For preventive maintenance would inspect and look for caps in hot places. A good indication is when the plastic casing pulls back. The only time replacing every cap is in antique radios.
Great video! 😅You've given some very good advice about boards and caps. I'm just getting started with this stuff as a hobby and i'm glad I watched this vid. It will undoubtedly save me from many wasted hours and from creating problems that wouldn't have been problems if only the required repairs were done. I'd love to see you get more Sansui pieces and other 70s gear on your repair bench.
Im an electronic hobbyist for 40 years and like to repair vintage hifi stereos for my personal use. I like your comment that doing full recaps and transistor replacement because they’re old or might go bad is not necessary. If you’re a retail store selling full price gear then I guess customers deserves that. But I agree with you…. for me personally I fix the problem address any issues, check and set voltages, put the scope on it and if all looks good then I just enjoy it. Long Live Rock 🤘🤓🤘
I'm 58 and my oldest brother had a Sansui 9090DB on a pair of Technics SB7000A speakers back in the mid to late 70's. When you hit the power switch on it the lights in the house would dim for a second.
You are wright about recapping 100 % . I thing new series of cheep elcos is as bad as old series after 30 years in charge . any way - trying to achieve satisfaction with wasting money for no reason is very good for servicers most of time 😏 👍
You might have a point that new caps made today are about equivalent to 30-year-old caps made 30 years ago. The chemical makeup of the electrolytic 30 years ago was totally different than what is in new capacitors. The new ones are going to sound different then the old ones. That was my experience about 10 years ago when I did a total restoration on I think it was a Kenwood integrated amp for a client. It was before I was doing the videos I wish I had filmed it because even though to my ears what I changed out all the capacitors it sounded fine to the owner he wasn't happy it had me go back and put all the old ones back in it again. In his case there was nothing wrong with his amplifier he just read on the internet that because of its age they all should be changed so he bought the kit and didn't want to do it himself brought it to me to do well I had to do it a second time to put all the other ones back in and I made some money on that one because I charge them to change them back. If you saw the lexman I did yesterday I did change some of the Caps I didn't do them all I changed 10 of them in the audio circuit of the actual amplifier itself but every single one of those old caps I pulled out was still within spec so they were changed they made no difference to the sound I changed them just because they were old there was a couple that were bad there was two of them that were bad the other ones were fine and I didn't bother with the main filters because they tested to spec.
@@12voltvids Yes that it's , but only thing that I'm not sure is - the new series of capacitors life time and functionality ??? I can't believe because everything in electronics are becoming cheaper and smaller - but in Hi-Fi cheaper by default is Bad ! 👍
Not funny at all. You're just displaying your ignorance. Vintage Sansui is super equipment, from both a design and build viewpoint. Have you actually worked on and successfully repaired any of this type of equipment, or are you just trying to be smart?
@@CondorAudio someone else brainwashed. It's ok. Nothing to write home about. I have same receiver and it is ok but certainly doesn't sound as good as my crest. My luxman sounds superrior too. There is nothing wrong with these old sansui but they were not better than any other of the same vintage all these old units sound the same. Quite high in the distortion dept most apparent in low volume listening.
I dont see an issue with recapping a whole unit if someone has the money to do it, I see it as preventative maintenance in some sense, all components have a life span/MTBF and electrolytics are a bit of a weak spot - what might test fine now might not in a years time, especially with a part that has had decades and decades and decades of use. Recapping a whole unit might mean it lasts a good while longer before it has to end up on the bench again (which could of course happens if a semi conductor finally decides its had enough).... What i dont believe in though is just shotgunning a unit and replacing all the caps in the hopes a fault will disappear (without even bothering to troubleshoot) - far better to troubleshoot, find the issue, replace the defective component(s) - if someone wants to do a full recap at that point after a problem has been fixed and has money to burn I dont see it as wrong personally.
Or something wrong with fully recapping a unit if you want to throw money at it as long as a person doing so understands it is not going to sound the same as they are used to. Is it going to sound better or worse now that's up to the listener. The amp that I did about 10 years ago to my ear sounded just fine with a new capacitors in it. But the guy that had it to him sounded like crap because he was used to the sound of the old caps. And that's what I'm getting at, the sound is going to be different because of the chemical makeup of the electrolytic. Even the physical size makes a difference a 100 microfarad capacitor from 40 years ago is physically much larger than a 100 microfarad capacitor today even though electrically they are the same. The physical aspects also affect the sound even though the electrical characteristics are the same. I know it sounds weird to hear someone say that while if it's 100 microfarad capacitor what's the big deal well it's the physical size of the plates the physical separation of the plates the dimensions internally affects the sound quality and it affects it more than most people will realize. The same is is it 85° or 105° temperature reading that changes the sound quality. So many of those old caps you can't get anything that's even close to the design of the original and it's going to change the sound and as long as someone understands that it is going to change the sound if you want to spend the money on it knock yourself out but just keep in mind that it is not going to sound the same as what you are used to hearing. and when I get the comments like if I wanted to sound like a new piece of junk that I could bought off the shelf today I would have gone and bought a new one and that was basically what "Steve" was whining about. It didn't sound like it used to to him it sounded very sterile like a modern amp and not like what he was used to listening to and to his ears it was unacceptable, so I put it back the way that it was and he was happy. Needless to say he is never and I have had him as a customer many times since then because he brings me everything that he owns that breaks down, he is never asked me to do a full recap on anything since. it's not like changing the oil on your car what you do at regular intervals because the oil wears out and then you don't have the same protection to your engine, capacitors will eventually fail for sure but it's the same ones that keep going bad all the time and those are the ones that are under high stress, the other ones that are not put under maximum load and high currents they will go on for decades without failing. The exception of course to this rule is the paper caps that were used in the early tube radios. The problem with those capacitors was the paper that was used in them. Acid in the paper over time caused the paper to become slightly resistive and because of the high voltages involved you ended up with slight DC leakage across the plates. Vacuum tubes being such a high impedance device even the tiniest amount of DC leakage was enough to bring the next stage into conduction. This is left unchecked would eventually need to red plating of tubes and tube failure transformer failure etc. In a transistor amp if you had a coupling capacitor then it become electrically leaky it was certainly upset the balance of a class A B amplifier and eventually lead to some DC to the speaker terminals which would then trip the speaker protection circuit and shut the amplifier down. But because the voltages in solid state equipment is very low and transistors are low impedance device a capacitor would have to damn near short to get to that point where you would trip a fault. typically what happens when they wear out is the sound just becomes bad and you hear it. Loss of trouble or loss of bass, when caps are bad in a power amp you know it because it just doesn't sound very good. It's usually filter capacitors that go bad and you'll hear them too as hum like that pioneer I had back a month or so ago that I had to change a handful of caps in it. Note that none of them were in the audio chain they were all power supply, all in the voltage regulation circuit and decoupling circuit. That was the one where I had to look at the tone board because the tone board wasn't working correctly it turned out that some prior servicer had shorted the bypassing switch so both the tone controls and flat were being fed through. Pretty obvious that whoever worked on that didn't have a clue the tone wasn't working so he just shorted the switch so that the tone controls would appear to work. I missed it initially because I got the amplifier in with just severe distortion and fix that problem. Clean the controls spun the base and treble up and down heard it changing a little and left it. The owner tried the tone bypass switch and realize that it wasn't doing anything so I looked at it again only to find that the tone board had been bodged, so I did some more troubleshooting and found two capacitors on the tone board that were causing the problem. Now getting back to preventative maintenance, the big problem with going in and recapping every capacitor on every board is that you are running a greater risk of causing other damage while you were disassembling and reassembling. Just like that big Akai reel to reel that the customer recapped before bringing it to me. it has a record problem now which I certainly didn't cause because I didn't touch anything anywhere near any of the other boards other than change the belt and adjust the bias on the amplifier boards but it doesn't record, and I think if I ever get permission to spend the money and time to dig into this and it certainly is not going to be cheap because I've wasted 5 hours on it already but root cause is going to be something that was damaged when all the boards were removed to change all the Caps that didn't need to be changed. That's the real risk of recapping any equipment it says very easy to cause other damage while you're working on it especially when you've got circuit boards that are 45 or 50 years old just waiting to break, and then there's the semiconductors that are going to be disturbed while you are removing and inserting new parts. It's not good to bend the leads on semiconductors any more than necessary, not only can the beach break off but on very old components like this the actual seal where the leads go through the case and into the junction can become loose just from deterioration of the potting material that the transistor is made from. Nudge a transistor while changing a cap that's next to it for example may cause the junction internally to fail just from mechanical shock. It's much harder to find old obsolete transistors these days. That's probably a more important reason for leaving well enough alone if it's working. Suggesting that the capacitors might fail in a year and they might they might not but then that transistor might also fail in fact it might feel a lot sooner if you disturb it. what has to remember this old stuff was never designed to last 45 or 50 years even way back then it's all on borrowed time.
Also wait till interconnect wires break off, or you take them off and make an error putting them back. Just because have 2 wires of the same color going to a board does not always mean they are interchangeable. The older equipment ran cooler so most caps didn't get pushed too hard.
@@12voltvids I guess not everyone's ears are the same... In the case of 'Steve' perhaps the amp had a different sort of frequency response after being recapped. It would have been interesting to see the response curve of the amp before and after the recap, along with the THD of the unit before and after. But going back to everyones ears being different, as you said in the video, the unit sounded absolutely fine after the recap..... There will always be 'that person' who claims it sounds different... Did it sound different to your ears after putting the old caps back in the unit? lol.
I know nothing about this stuff, but I find it fascinating to watch anyway.
When recapping a receiver or amplifier, quite often the unit will sound like crap until the capacitors form and settle in to their happy place.
It take up to a couple of weeks for the caps to settle in. The amp won't sound it's best until this happens.
That's from my experiences and not something I read on the internet
Possibly. The one I did the guy did listen to it for several days though. It wasn't that he came back the same day as i tried to defuse him as i didn't want it back. He paid me only 30.00 to put it back and that was considerably less than I charged to do the initial work.
Most bad capacitors I've seen have been in gear from late nineties early 00's, when China started stealing and badly replicating cap recipes. Ancient Elna and Rubycon caps almost always measure ok!
Had my 9090 completely rebuild! Love how it sounds!
Nice and distorted like all those sansui. Swapped mine out for a 900 watt Crest. No going back.
My cat was trying to talk to your cat
Thanks for this video Dave 👍🏻🙂. Appreciate the explanation on recapping. I’ve done just that on some 90’s gear which didn’t help me resolve a problem and it was frustrating to say the least. I’ll focus more on what else can cause issues.
Capacitors cause specific problems. Yes doing a total recap will fix a problem if it is caused by a capacitor. Troubleshooting and replacing that one cap will also fix it. It won't fix a problem caused by a bad transistor, diide6, resistor, diode, inductors, crystals, or solder connections.
funny thing , i ve did lots of solder joints on a cassette deck logic board , and it became TOTTALY unresponsive , almost like it was dead.
Cleaned the flux with flux cleaner , problem gone.
Wierdest thing that i ve encountered , ever.
28:40 Steve didn't let it run for a couple of days? Immediately on new caps, anything sounds like crap before it mellows after a bit of cooking time.
33:36 capacitors and people, it's a mental condition, I'm convinced, and good for you for pointing that out - knee jerk reaction = caps! There is a lot more as you rightly point out. Preamps, etc I've noticed no significant improvement with swapping caps - older power amps? sure - swapping low value elec with film in signal, usually a good thing if you have the patience to cross reference and purchase.
Actually it was about a week before he returned whining about it and was back and forth a few times before i agreed to changing them back and only after he paid me up front so he wouldn't screw me over for the rework.
@@12voltvids yeah, wow.. mental.. Great vid though.. 👍
APPRECIATED
it has good sound
Hmm quality sewage 😀
I have never been a mass capacitor replacer, only the ones that look or read bad.
If a known failure then replace it.
Where people got the idea of mass capping i don't know.
That daft owner that demanded a mass re-capping is a Asshole (Technical Description).
Your cat just wants a little attention, it seems like a happy pet.
Some cats are only Fuss and Food, then they piss off lol.
But I think is laughable is there are some certain high-end amplifier manufacturers that will recommend full cap replacement after 10 years. Of course this is just a money maker for their dealer Network if the manufacturer suggests that this has to be done some people will be silly enough to spend $1,000 and I'm sure that these boutique manufacturers would be charging that much for their repair kit, to do it. Although modern ones they probably are shot in 10 years because the environmentally friendly ingredients and construction of new caps a tend to not last anywhere near as long as the old ones wishes that really bad chemicals. As to the cat paid me a visit she was probably trying to tell me that she was hungry. That's typically the only time I see them when they want something other than that you're right they're off sleeping somewhere. I try to keep them out of the shop as much as possible because there are a lot of hazards in here. Dirt bits and pieces from equipment being worked on ends up on the floor and they like to roll around on the ground because it's nice and cool and they get all that crap on their fur and then go and lick it and could ingest something that could make them sick so I generally try to keep them out of the workshop. Little bit of snipped off wire for example could be fatal if they were to swallow it.
Most likely from caps' manufacturers listing 15 years as the guaranteed lifetime of the rubber seal in pretty much every data sheet I came across. For many, that's enough of an incentive, even slightly elevated ESR and somewhat leakage, might be another.
@@paulb4661 they actually used to rate them in hours depending on what they were designed for. As low as 8,000 hours for some and others as high as 60,000 hours. I have a sharp LCD monitor that's used for my security cameras and it's left running 24/7. Last time I checked it it was sitting at 68,000 hours and still going strong. The new modern capacitors are not designed to last anywhere near as long as the older ones were and a lot of it has got to do with the chemicals that are in them. The newer ones I rated at a much lower lifetime because of how they're constructed much lighter materials and smaller physical size. This increases the likelihood that rubber seals are going to fail a lot sooner on newer than older capacitors.
@@12voltvidsThe rubber seal quandary is all but a single sentence, hidden amongst other superfluous data. It has to do with allowing for thermal expansion, whilst keeping electrolyte escape levels to the very minimum at the same time. Many, many well made caps will happily get past the goal post and continue to perform well into their pension, especially if reasonably sized and not stressed to the limit during their lifetime. Many modern miniatures, especially those manufactured to the highest standard in a certain Far Eastern country, will fail, often spectacularly before they even get going. With antique, prized posessions, re-cap by all means with whatever you can squeeze in there. They dont make them like they used to and it only takes one leak to possibly send some of unobtainable ICs to Valhalla. With more modern, high quality equipment, where lower tiers caps found a home, I wouldn't hesitate either. Had 50 year olds indistinguishable from brand new, similarly sized equivalents, but also had many dried out and acting partly as resistors. Had some leaking, both colloquially and literally speaking, but also had some in their teens, half dead, with burst seams 🤦♂️
@@12voltvids Yep cats = FF Food and Fuss.
They are selfish little gits but we like pets.
I liked dogs better as they are always happy to see you and never judge you.
But they can be as thick as sh-it.
Dogs need walking and for some people it's an excuse to wander around with no set destination.
Can you please stop leaving HDMI and kettle leads hanging over your screen please? I watch you on a large screen TV and they look life size on my screen! I keep thinking 'who left a lead hanging over my TV ', it's confusing. Larry
😁😃😅😆😄🤣🤣😁🙂🙃😉🤗
I'll guess. Transistor. But I'll watch to see if I'm right or wrong.
Edit: not exactly. Btw, soldering to me is a skill I have trouble mastering. I guess I need more practice. Those ladies must have been very good.
To start with, you are my electron sensei. I have been an auto and boat wrench all my life, specializing in electronics installation and integration. With the help of your 12volt vids I was able to get my NAD 7155 working. My NAD 2200 is a different story. Not sure what I did but it likes to make smoke now. I noticed one transistor had a solder joint that looked like the loose one you found. I pulled it and checked it with my ohm meter, seemed ok, put it back in and presto more smoked resistors, about 4 of them . This is an adventure and I love it. Thank you and and keep the great info coming!!
money root of all evil ???????????????????????
Have never had to worry about that.
In my Nelson Pass Aleph 3 Amplifier brochure, he specifically states after 10 years of use you should replace the capacitors. I believe Pass
Just trying to milk you for more money.
10 years of constant use he means? = 87,600 hours.
That thing looks a lot like a Pioneer receiver I have, inside and out. Is there a crossover with those companies?
Can low temperature solder help prevent the pads or traces from lifting? Pros and Cons transistor heat can cause the solder to melt and cold solder joint.
Not really. Low temperature solder has its own problems all you have to do is look at all those RCA TVs made in the 1990s with the integrated tuner and how many problems they had same with Sony with in the 80s and '90s all the problems in their tuner modules that were all put together with low temperature solder.
I concur, I ran a repair shop for 35 years, in all that time I never did a full capacitor replacement on any amps that I repaired, it was completely unnecessary.
It's a money maker for shops these days. Just like the crook at the local tire shop. Took my old truck in there about 4 years ago to get the driver side half shaft replaced because it was clunking. Once "Andy" got it in the shop the estimate of 600 jumped to 1300 because he said it needed both and he was unable to just change one because the other was worn and used a bullshit unsafe vehicle claim to say he couldn't and wouldn't just replace the single bad part. Held me hostage. I was selling it and didn't want it making noise for the new buyer. Did i care if the other one wore out next year? No, it had 185,000km on it. So i put 1300 into a vehicle that ultimately i sold for 1000 because the crook on the corner held my truck hostage. His name isn't Andy by the we at but it rhymes with it. Any local reading this will know exactly who i am talking about. sucks to be home because i tell everyone about it and I have not been back there for tires since. That tactic lost him a customer (me) that he had for over 20 years. Do what your customers ask and nothing more. Padding your bottom line and taking customers for a ride is a good way to loose smart customers. Dumb ones that believe the bullshit well they deserve to get taken for a ride.
i bet steve's name is steve ahahah
Might be. Sorry Steve you knew i was going to call you out.
Nice job.
Long before the change all the caps thing came about, when I got a repair in would troubleshoot and repair the problem. For preventive maintenance would inspect and look for caps in hot places. A good indication is when the plastic casing pulls back. The only time replacing every cap is in antique radios.
Correct.
Great video! 😅You've given some very good advice about boards and caps. I'm just getting started with this stuff as a hobby and i'm glad I watched this vid. It will undoubtedly save me from many wasted hours and from creating problems that wouldn't have been problems if only the required repairs were done. I'd love to see you get more Sansui pieces and other 70s gear on your repair bench.
Im an electronic hobbyist for 40 years and like to repair vintage hifi stereos for my personal use. I like your comment that doing full recaps and transistor replacement because they’re old or might go bad is not necessary. If you’re a retail store selling full price gear then I guess customers deserves that. But I agree with you…. for me personally I fix the problem address any issues, check and set voltages, put the scope on it and if all looks good then I just enjoy it. Long Live Rock 🤘🤓🤘
I'm 58 and my oldest brother had a Sansui 9090DB on a pair of Technics SB7000A speakers back in the mid to late 70's. When you hit the power switch on it the lights in the house would dim for a second.
You are wright about recapping 100 % . I thing new series of cheep elcos is as bad as old series after 30 years in charge . any way - trying to achieve satisfaction with wasting money for no reason is very good for servicers most of time 😏 👍
You might have a point that new caps made today are about equivalent to 30-year-old caps made 30 years ago. The chemical makeup of the electrolytic 30 years ago was totally different than what is in new capacitors. The new ones are going to sound different then the old ones. That was my experience about 10 years ago when I did a total restoration on I think it was a Kenwood integrated amp for a client. It was before I was doing the videos I wish I had filmed it because even though to my ears what I changed out all the capacitors it sounded fine to the owner he wasn't happy it had me go back and put all the old ones back in it again. In his case there was nothing wrong with his amplifier he just read on the internet that because of its age they all should be changed so he bought the kit and didn't want to do it himself brought it to me to do well I had to do it a second time to put all the other ones back in and I made some money on that one because I charge them to change them back. If you saw the lexman I did yesterday I did change some of the Caps I didn't do them all I changed 10 of them in the audio circuit of the actual amplifier itself but every single one of those old caps I pulled out was still within spec so they were changed they made no difference to the sound I changed them just because they were old there was a couple that were bad there was two of them that were bad the other ones were fine and I didn't bother with the main filters because they tested to spec.
@@12voltvids Yes that it's , but only thing that I'm not sure is - the new series of capacitors life time and functionality ??? I can't believe because everything in electronics are becoming cheaper and smaller - but in Hi-Fi cheaper by default is Bad ! 👍
@@stivkrunic8612 not necessarily this is perceived by some. There are excellent new audio products that are superrior to old stuff.
very good
Hey Dave it's a San -Sewage! LOL
😄
Not funny at all. You're just displaying your ignorance.
Vintage Sansui is super equipment, from both a design and build viewpoint.
Have you actually worked on and successfully repaired any of this type of equipment, or are you just trying to be smart?
@@CondorAudio someone else brainwashed. It's ok. Nothing to write home about. I have same receiver and it is ok but certainly doesn't sound as good as my crest. My luxman sounds superrior too. There is nothing wrong with these old sansui but they were not better than any other of the same vintage all these old units sound the same. Quite high in the distortion dept most apparent in low volume listening.
I dont see an issue with recapping a whole unit if someone has the money to do it, I see it as preventative maintenance in some sense, all components have a life span/MTBF and electrolytics are a bit of a weak spot - what might test fine now might not in a years time, especially with a part that has had decades and decades and decades of use. Recapping a whole unit might mean it lasts a good while longer before it has to end up on the bench again (which could of course happens if a semi conductor finally decides its had enough).... What i dont believe in though is just shotgunning a unit and replacing all the caps in the hopes a fault will disappear (without even bothering to troubleshoot) - far better to troubleshoot, find the issue, replace the defective component(s) - if someone wants to do a full recap at that point after a problem has been fixed and has money to burn I dont see it as wrong personally.
Or something wrong with fully recapping a unit if you want to throw money at it as long as a person doing so understands it is not going to sound the same as they are used to. Is it going to sound better or worse now that's up to the listener. The amp that I did about 10 years ago to my ear sounded just fine with a new capacitors in it. But the guy that had it to him sounded like crap because he was used to the sound of the old caps. And that's what I'm getting at, the sound is going to be different because of the chemical makeup of the electrolytic. Even the physical size makes a difference a 100 microfarad capacitor from 40 years ago is physically much larger than a 100 microfarad capacitor today even though electrically they are the same. The physical aspects also affect the sound even though the electrical characteristics are the same. I know it sounds weird to hear someone say that while if it's 100 microfarad capacitor what's the big deal well it's the physical size of the plates the physical separation of the plates the dimensions internally affects the sound quality and it affects it more than most people will realize. The same is is it 85° or 105° temperature reading that changes the sound quality. So many of those old caps you can't get anything that's even close to the design of the original and it's going to change the sound and as long as someone understands that it is going to change the sound if you want to spend the money on it knock yourself out but just keep in mind that it is not going to sound the same as what you are used to hearing. and when I get the comments like if I wanted to sound like a new piece of junk that I could bought off the shelf today I would have gone and bought a new one and that was basically what "Steve" was whining about. It didn't sound like it used to to him it sounded very sterile like a modern amp and not like what he was used to listening to and to his ears it was unacceptable, so I put it back the way that it was and he was happy. Needless to say he is never and I have had him as a customer many times since then because he brings me everything that he owns that breaks down, he is never asked me to do a full recap on anything since. it's not like changing the oil on your car what you do at regular intervals because the oil wears out and then you don't have the same protection to your engine, capacitors will eventually fail for sure but it's the same ones that keep going bad all the time and those are the ones that are under high stress, the other ones that are not put under maximum load and high currents they will go on for decades without failing. The exception of course to this rule is the paper caps that were used in the early tube radios. The problem with those capacitors was the paper that was used in them. Acid in the paper over time caused the paper to become slightly resistive and because of the high voltages involved you ended up with slight DC leakage across the plates. Vacuum tubes being such a high impedance device even the tiniest amount of DC leakage was enough to bring the next stage into conduction. This is left unchecked would eventually need to red plating of tubes and tube failure transformer failure etc. In a transistor amp if you had a coupling capacitor then it become electrically leaky it was certainly upset the balance of a class A B amplifier and eventually lead to some DC to the speaker terminals which would then trip the speaker protection circuit and shut the amplifier down. But because the voltages in solid state equipment is very low and transistors are low impedance device a capacitor would have to damn near short to get to that point where you would trip a fault. typically what happens when they wear out is the sound just becomes bad and you hear it. Loss of trouble or loss of bass, when caps are bad in a power amp you know it because it just doesn't sound very good. It's usually filter capacitors that go bad and you'll hear them too as hum like that pioneer I had back a month or so ago that I had to change a handful of caps in it. Note that none of them were in the audio chain they were all power supply, all in the voltage regulation circuit and decoupling circuit. That was the one where I had to look at the tone board because the tone board wasn't working correctly it turned out that some prior servicer had shorted the bypassing switch so both the tone controls and flat were being fed through. Pretty obvious that whoever worked on that didn't have a clue the tone wasn't working so he just shorted the switch so that the tone controls would appear to work. I missed it initially because I got the amplifier in with just severe distortion and fix that problem. Clean the controls spun the base and treble up and down heard it changing a little and left it. The owner tried the tone bypass switch and realize that it wasn't doing anything so I looked at it again only to find that the tone board had been bodged, so I did some more troubleshooting and found two capacitors on the tone board that were causing the problem. Now getting back to preventative maintenance, the big problem with going in and recapping every capacitor on every board is that you are running a greater risk of causing other damage while you were disassembling and reassembling. Just like that big Akai reel to reel that the customer recapped before bringing it to me. it has a record problem now which I certainly didn't cause because I didn't touch anything anywhere near any of the other boards other than change the belt and adjust the bias on the amplifier boards but it doesn't record, and I think if I ever get permission to spend the money and time to dig into this and it certainly is not going to be cheap because I've wasted 5 hours on it already but root cause is going to be something that was damaged when all the boards were removed to change all the Caps that didn't need to be changed. That's the real risk of recapping any equipment it says very easy to cause other damage while you're working on it especially when you've got circuit boards that are 45 or 50 years old just waiting to break, and then there's the semiconductors that are going to be disturbed while you are removing and inserting new parts. It's not good to bend the leads on semiconductors any more than necessary, not only can the beach break off but on very old components like this the actual seal where the leads go through the case and into the junction can become loose just from deterioration of the potting material that the transistor is made from. Nudge a transistor while changing a cap that's next to it for example may cause the junction internally to fail just from mechanical shock. It's much harder to find old obsolete transistors these days. That's probably a more important reason for leaving well enough alone if it's working. Suggesting that the capacitors might fail in a year and they might they might not but then that transistor might also fail in fact it might feel a lot sooner if you disturb it. what has to remember this old stuff was never designed to last 45 or 50 years even way back then it's all on borrowed time.
Also wait till interconnect wires break off, or you take them off and make an error putting them back. Just because have 2 wires of the same color going to a board does not always mean they are interchangeable. The older equipment ran cooler so most caps didn't get pushed too hard.
@@marka1986 i fear this is what happened on the akai reel to reel that the owner did a full recap and then dumped it on me.
@@12voltvids I guess not everyone's ears are the same... In the case of 'Steve' perhaps the amp had a different sort of frequency response after being recapped. It would have been interesting to see the response curve of the amp before and after the recap, along with the THD of the unit before and after. But going back to everyones ears being different, as you said in the video, the unit sounded absolutely fine after the recap..... There will always be 'that person' who claims it sounds different... Did it sound different to your ears after putting the old caps back in the unit? lol.
Also curious, what was the age range of this customer? My hearing has only degraded as I have gotten older. lol.