Amplifier maintenance 101 - Cleaning Controls & Re Capping a Receiver (Featuring the Yamaha CR820)
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- Опубліковано 18 лют 2023
- This video started out as a repair/restoration video, but beyond replacing the power cord and cleaning the controls, everything else seemed to be working well. As a result, I decided to show some tips and tricks to cleaning the controls and "re-capping" the receiver. As fate would have it, the first capacitor I removed was bad! Talk about unexpected. The next thing you know, I am testing and comparing different capacitors to see how a capacitor's specs can affect the performance of the circuit. Anyway, it was fun!
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0:00 Intro
1:09 First power-up. Checking for DC on speaker terminals
2:45 First attempt at playing some audio through the receiver
4:07 First look inside - cleaning the volume pot and trying once again - success!
8:05 How to clean the potentiometers
26:37 "Re-capping" a receiver - some thoughts and experiments
explained well, you cover it well
I usually use brake cleaner, simple and crude
I've heard dramatic differences after a re-cap. Of course, removing 40 year old caps and replacing them with new will bring the circuits back in balance. The two channels start to sound identical again and that's the magic we're all looking for.
Caps all age differently, even the same cap in the opposite channel can have wildly different readings on meters. I say re-cap with new, fresh good quality caps and enjoy the sound.
Edit;
Another thing I should note. I've recapped amplifiers and have them sound horrible after. Another two weeks or so of daily listening and they will wake up and sound great.
I'm guessing the caps need plenty of time powered up to settle into their new role
what caps did you use? i use nichicon golds and i have not noticed a change of character ever with those.
@@sgredsch I suggest you should have a look at Trevor's channel :) He's plenty of great repairs there.
Thank you for the demo, and tip, on the Nichicon "FG vs KT" capacitor performance. The KT's are 105C rated, whereas the FG's are 85C, and the KT's are also usually only available in higher max voltage ratings than the FG's, but if one was looking for longevity it does seem that the KT's are the better choice, and they are also priced a bit lower than the FG's . I have a few amps to do reworks on the driver board for, and I am going to choose the KT components going forward, especially on the 2 - Harmon Kardon Citation 16's I have, as the driver boards aren't far from the power output heat sinks, and the "normal" idle bias current keeps those heat sinks about 60C
😂😂😂 “spray and pray!” Love the use of that one. I’ll have to use that. Thanks for the video. Thank you for the comments on those spray nozzles. They suck, and I email every company I buy from to get rid of it. They probably ignore mine, but if we can get everyone to make noise, maybe…. meh probably just a pipe dream.
Hello Tony,
Really appreciate you covering each of the topic's in this video. It would be great if you could expand on circuit identification (power, audio path, frequency etc. ) and how that relates to capacitor selection.
Thanks for the good video and instructions, including the WD-40 part. I think a re-cap and chat will be nice! I agree that re-capping will be a good idea for the long-term results and enjoyment of the sound out of the equipment.
Tony , you put the fingerf on a very sensible issue..........and with WISE advice !!!
Another great video on a subject many want to learn about! The verbal cues are always on subject, the end results are a meaningful education! Thanks for all!
I grabbed 2 - 820s last year for a very low price. 1 was like new and 1 had a couple scratched knobs. Recapped, lamps, pot cleaning a few new knobs and 1 new relay. Both look and sound fantastic.
Also, I do use WD-40 to clean and shine the back panel on vintage audio.
Thanks Professor! Enjoyed watching and learning.
It was great to see the info about contact cleaners. I've been picking up bits and pieces from various videos. One additional thing I'd like to see is some discussion about the best way to clean flux from boards after changing components, especially when the board is still in the receiver/amp. Maybe you've covered it already somewhere. I've watched around 30 of your videos so far. I'm about to start a recap of my SX-1010, and I'd like the job to look as professional as possible.
I always enjoy Tony's "cap-chat" talks.
Hi Tony i do repair and recap those amps too.i find your right, replacing electrolytes if coupling signal to mkp type caps.
I think in those days when the Yamaha was made they had to order parts which where expensive. And nowadays they are not expensive anymore. Nice video and as always with respect to your viewers
I always learn something watching the xray boss.
Thanks Tony!
Tony, I think it’s great that you take time to inform viewers about the products and techniques you use. That can be really helpful to those DIY people that need the information. As always, I really enjoy your videos. 👍🏻
Thank you, thank you for taking the time to break down the various control cleaning products. So much misinformation and confusion info out there. I couldn't believe the video where a guy throws a carbon rod in some DeOxit as if anything was going to happen 🤪 it's the binding agents that is a concern!
Thanks for stopping by, Bob! Hopefully, this will clear things up for some folks.
Thank you for the demonstration of the electrolytic capacitor's capacity to frequency, so the problem is not just ESR.
I always re-caping old electronics, even new ones with unknown brand capacitors, not just audio amplifiers. Maybe I was crazy changing the looking good electrolytic. I just don't trust old electrolytic capacitors or unknown-brand capacitors.
I have a 20 year old Cosel SMPS, it was very hot when on, recapping all the electrolytic (only 4) and now it runs cool.
Superb information clearly explained and invaluable for an amateur like me while going through the selection process to replace capacitors in older hifi gear! THANKS MUCH.
As usual, great video Tony!
I would love to see you take a look at the FM tuner section and OTS(Optimized Tuning System), which includes a touch sensor circuit that disables the OTS whenever you touch the tuner knob. I'm working on one of these right now with MPX decoding issues, complicated by the OTS circuits.
Thanks for the many videos!
Great video about capacitor test result relevance!
Very good explanation on capacitor behavior and testing. Nice that you did the capacitance and tan D comparison on the different frequencies and presented it in the table! I often just make a few measurements on some of the different caps before deciding to or not to recap. Also depends if the unit is going to be in regular use
This was great! I believe in re-capping any vintage quality equipment. My HH Scott 387 caps, many read higher cap values. I don't have my leakage tester built yet but think maybe leakage made them read higher than spec. Also after cleaning carbon pots and a bit of fader lube I use this moving contact lubricant by Caig Industries - maybe overkill. I always worry about the slider wearing the carbon trace. Thanks for the cap comparisons I like the LCR meter.
What a pretty Yamaha Receiver 😍 I love Yamaha Design. My collection is C-4, M-4 & PF-800.
Nice video as always...really appreciate the in-depth information. I always learn something and I aspire to be as thorough as you one day. Take care!
Tony, Quite the excellent cap comparison at the end. especially those higher frequency results. Nice Work!!
Yes. I enjoy the chat videos as well!
Based on that 1 original cap, I would tend to recap that receiver. Like you said, if 1 or more are showing deteriorited than most likely they all are needing replacement.
Love the well explained parts .. they dont leave me wondering. I'm starting to look at my dad's old Pioneer so just doing some self educating here with some vids, and yours are among the best !
Keep your old spray nozzles when the can runs out! Those awful leaky DeOxit spray nozzles pull straight off and a regular nozzle (which you can put a straw in) fits in its place
I have this receiver and want to recap. Found a good list on AudioKarma from a guy who did it. How can I be sure I’m not putting the wrong caps in and inadvertently change the sound? This is so informative. Thank you.
Hello Tony B!! I am a huge fan of yours and your Channel. I have been watching yours and others like Mr. Carlson's LOL! But I just wanted to say. I love old solid state elctronics myself. I am trying to learn all you do on my own with no schooling. I do have somewhat of a basic knowledge about electronics. I also wanted to say that I think your awesome and you make things easy to understand. As I try to follow then I get lost haha! I also think you would make a GREAT teacher and it would be a dream of mine to learn beside someone like you hands on. I am an electrician and handyman by trade. But I want to get more into electronics radio repair and knowledge of vintage tech equipment. Anyhow I can go on forever. Love your channel I think your great huge fan Joe from Quebec Canada!! cheers buddy!
Very informative. And yes I'd like to see the recap. Not that i do not know how to. But all the stories and anecdotes that will probably follow would be most entertaining.
Used to prefer the old Chemtronics cleaner that had CFCs (before the manufacturer was forced to remove them from the formula) Preferred it so much I purchased 24 cans before the ban. Good stuff! The post-CFC ban product was quite inferior!!
The problem is that continuing to use those products is releasing CFCs into the atmosphere, damaging the ozone layer. Please do locate some equivalents which don't contain them so you're not participating in that issue going forward. If the replacement you originally used didn't work well for you, try another one.
1:02:14 Obviously re-cap. The sound will potentially roll-off with the caps in the signal path and, as pointed out, its good insurance. For the power supply caps, the re-cap will ensure longevity, but would I suspect help keep the voltage up with large infrequent transients. I was surprised with the initial results for the FGs; I use them all the time in the signal path (I used to use Panasonic FCs for power supply caps, but sadly the FCs are no longer made) but shelf life, or indeed ultimate life might be an issue for them (they could re-form of course, or they might not..). The Silmic was excellent.
Thank you for the information on capacitors using an LCR meter as well as the liquid cleaner types. 🖖
This is the best explanation on capacitor testing and aging i seen. I did not understand the values until now!
It confirmed my experience in recapping 2 20-30 year old amplifiers. While i had no idea about his until now, i just bought all SILMIC 2 reasoning its quality and that the way to go it you know little, and it showed on sound extremely. Both amps (Harman Kardon HK6200/Rotel-931) where totally crazy harsh and unnatural sounding after recap for a month, but turned in to beautiful sound after that initial period.
Thanks for your videos Tony, they are very informative. Thanks for sharing.
43:00 Those orange capacitors, I remember I replaced the 3 low leakage capacitors on 2 motor servo boards on a Pioneer RT-707 and a RT-701 with ordinary black ones when I recapped the PCB's. ( one 4.7uf 50v, and two 2.2uf 16v )
For years I have wondered why the speed had issues on both machines. I did some research and found the leakage current was supposed to be less than 0.027 microamps at the rated voltage on those. Yes it makes a difference. The eye opening of my Heathkit IT-28 on the most sensitive paper/mica setting, 2 uA, does not even show any leakage. I needed to hook up a micro amp meter in series to see the current. Now I need the correct replacements and have to replace them. Lessons learned 🤨
Elna CERBs are hard to beat in that respect even by Nichicon UKLs, however have the tendency to go way out of spec, have one 47/16 lifted from a power amp PCB measuring 11uF with 6 or 7Ω ESR. For values below 10u Wima MKS2s fit in nicely.
@@paulb4661 In some circuits I worry the rise time of a film cap may be too fast for the design and cause oscillation and ringing on square waves. Best to stick with engineered designs, I feel more comfortable with OEM unless I can know the results.
@@zulumax1 True, thankfully haven't turned any of the amps into a generator so far myself. In a larger sense, I think that size and progressively cost, as time went by, were the main factors favouring electrolytics over film caps in the majority of home audio products, rather than affording stability of the NF loop. Obviously, you may be in for a nasty surprise, if the ku is above 1 at the point the phase nears 180° out, but an RC is usually employed to keep the bandwidth reasonable.
Acids like Butyric acid can be neutralized by a base like baking soda or sodium bicarbonate. So dip your old screwdriver
in a solution of baking soda and hot water using a disposable cup. Spin the handle end around in it and watch for bubbles,
lots of bubbles. Guaranteed temporary fix for the smell. Wash the handle and dry it. The smell will eventually come back since the plastic deteriorates but if you spray an automotive clear coat spray over the plastic it will no longer smell.
I just watched this video, and though I’m not technical savvy, really enjoyed listening to your explanations. I don’t own a vintage receiver, I will never forget the sound of my late 60’s HH Scott 222c amplifier I inherited from my father. I would love to find a vintage unit that I could use in my studio. I’ve looked at eBay but without the knowledge to repair a piece, I worry I may end up with a bad unit. Sure would be nice to find someone in the DFW area which could be trusted.
Thanks for the video. I subscribed and look forward to watching some more.
I also subscribe to Mr Carlson and he uses his own designed Super sensitive Capacitor Leakage tester which you can get the plans for on his patreon. I built one and it is fantastic and detecting leakage.
Muy instructivo e interesante la información que haces al respecto de los capacitores electroliticos, la comparativa que haces entre ellos y el comportamiento real sea tan diferente o distinto teniendo los mismos valores de uf. Gracias, creo que tendre que tener muy en cuenta en los próximos recap de amplificadores vintage.Fantastico video mis felicitaciones tony.
At 37:00 in, I would recap the tone board mainly because tone circuit caps can cause problems even if somewhat marginal, and you already have the board out. And I'm not a re-cap guy.
I did recap of 45 years old Kenwood ka series amplifier after have a doubts what's worth it. Seemingly electrolitics were in the range of ESR and capacitance, all of them Elna and similar trusted marks. But after the complete recap, relay and current adjustment resistors change the sound at the out became so clear and natural what I don't regret about time and money investment on it. More, the smell of old heating amplifier was disappeared after two month of using the renewed amplifier!
I always learn something from Tony, know if I understood more about which cap's to use in which application...
Next project Tony. Solder and chat on recap is nice, but it shouldn't stand in the way for a new project video. I'd rather see a problem-solving video and the process of determining the fault and repair it. Other than that, great informative video, especially the caps part. I like the DER-DE 5000 meter. I might buy one in the near future. Also I would like to know your thoughts on types of caps. Which ones you use in the power rails for instance. And how to determine if the cap is in the audio path or not by looking at the schematics. Kind regards, your Patreon.
Thanks Tony, greatly enjoy this content….!
Great video! Thank you. 🙏🏼🙏🏼
Please do a full video on the actual soldering of the new caps. Well done. Cheers
Excellent video
Excellent info Tony ! Now you need to cover reforming caps and a video covering the others, ceramic, metal film etc. Thanks good solid info ! I trust your judgement based on facts...
Thanks Tony B - love the videos Been enjoying my Yamaha CA 810 paired up to my Polk Lsim 703 Sounds great ! For Pricepoint - wish you was in the states
Great video! The triangle logo with the M is Matsushita, the company that owned (owns?) Panasonic and Technics
Thank you Tony for your excellent work, wisdom and dedication to this topic! There are all kinds of opinions on the "to recap, or not to recap" subject. Many people will say the old caps sound better. How many of them can remember back to the mid 1970's when these were manufactured? I am sure that there are some, but did their hearing change as well? Keep up the good work!
My problem with ANY aerosol nozzle is that they're too 'touchy'. It's very difficult to regulate the flow.
Apply control cleaner with a syringe instead.
i have only done a few recaps, but most of the time the results were excellent and absolutely worth it. you should resolder all joints anyway, so its good practice to recap.
most caps i have pulled put measured fine, but the amp still usually sounds alot better after.
I will say, tho, that certain circuits with some foil capacitors in them will not improve as much or not at all. then its just service to improve lifespan.
I used nichicon golds and the blue ones - elna are really hard to get here. i always switch elko for elko - never tried a film replacement. and i will say that nichicon golds will produce a tube like sound that is very punchy in the lows and silky in the heights with very good imaging. i might try out mkt as bypass or replacement in high Audio frequency sections, but i have been very satisfied with the sound so far. its probably closer to the original Sound of the device than the technically better mkp caps.
considering that most modern high end stuff is either elna silmic or nichicon golds with wima mkp for smaller values, this is probably the best way to go.
Great primer tony!
That butyrate smell is really impressive when you mold the handles :) It's one of the 1st commercial plastics but is really tough stuff.
I saw a comment on UA-cam that capacitors are the bane of electronics. Seems like every video I see repairing electronics they replace capacitors and for a lot of the time seems to fix the problem. But not always. I'm mainly talking about repairs on Arcade Machines.
I would recap the signal path at a minimum. Yes, do a recap video too.
Hey Tony! Have ever tested say 10-20 Nichon or Selnas for consistency or avg production quality ?
Also be fun to try to squeeze some of the auto-grade caps onto a board to hear the outcome and check the overall performance ! Love your content! Definitely learn a lot from you, thanks !
Used to be more of a variety of cleaners. Tuner and control cleaner with or without a lubricant. Tuner Renu by Chemtronics took care of most controls. Saved the D5 (At that time was trademarked Cramolin) for when nothing else worked. It has always been very pricey. For now I've had good luck with CRC 2-26 for general control cleaning.
I just did one of these, it was nasty with failed transistors and messed about by someone else with a crack in the board etc etc. I just replace essential caps..and a couple were necessary..only if necessary. With stuff like this replacing all is the road to madness, there are about a hundred of em.. It ain't that good anyhow. Which is why I have amps (for me to listen) with two caps in the audio line per channel, both poly. Don't need to worry about crappy electrolytics. PS Check carefully soldering, mine was awful and needed a lot of going over. Use eyepiece.
Excelente Tony.
Looks like a well built Amplifier. Definately re-cap.
Thanks Tony!
I replace *ALL* Electrolytic's Period! I also only use DeoxIT!
I think a cap and chat would be a good idea… maybe talk about why you chose a specific capacitor..? Maybe talk about the pros and cons of upgrading to film caps...? Would film caps alter/sterilize the sound?.. etc..
Personally i'd always recap audio equipment. Even if the capacitors are still working, the values will have changed from how they originally were and the sound will be affected. It's like listening to the sound of dying capacitors *lol* Another thing I found interesting was, to see how the different capacitors performed. I always wondered how the Elna Silimic 2 capacitors were and if they weren't just audio mumbo jumbo, with silk inside for extra smooth sound *lol*, but they seem to actually be really good capacitors. Nice to know. Thank You for the Video ^_^
Good video as always. Although I don't have the same opinion in regards to WD40. It is pretty much all I use on my electric equipment for cleaning and lubrication of switches and potentiometers. The reason I choose that product is because more than one service manual from a reputable manufacturer of high quality oscilloscopes and other test equipment specifically mentioned their approval and included it in their field technicians service and repair kits. Just my 2 cents.
I think we may be talking about two different products. Unfortunately, WD-40 is the name given to several products. I'm assuming you are talking about the WD-40 Specialist contact cleaner, which is made for this purpose and is a good product at a great price. What I'm talking about is the original WD-40 muli-use product (and also their oil/silicone-based) products, which is a water displacer/lubricant/cleaner. It was not intended to be used on electrical equipment. If you look on the WD-40 website, they specifically state that the WD-40 specialist cleaner is the proper product to use. I didn't clarify that when I made my comment in the video. Thanks for the comment!
This is great!
So I guess we'll use automotive caps from now on?
How do you think a low ESR (SMPS) cap would perform in those tests?
Some time ago I did an extensive recapping on 80ies cheap HIFi and the results there were really noticeable (obviously the design was not so cheap as were the used components - I also used film caps for all values lower than 4,7uF).
It would certainly be great to see a video of you doing the soldering - there are so much little things you can notice this way ...
I wonder. Thanks for your explanation about the declining capacitance at higher frequencies. However, you make me wonder about the ESR + Cap meter I use. It does its test with 50 kHz - 100 kHz, but I don't see that (new) capacitors have really low capacitance at that test. It is always above the factory specs, or very close under it, except of course when dried out. In your test we see a decline to even 25%.
I use a Peak ESR70 Gold.
Another great video Tony 👍, itwould be interesting to see if the measurements change with the caps freshley formed. Also what was the film cap? Was it polyester or polypropylene?
Hey Tony, Great channel! Thank you for your work! On the schematics at the Phono input, there are cap's with an RB Mark, do you know what kind of cap's they are?
Tony, thanks again for a great video. Is there a way that you can record or sample the unit before you re-carpet and then after Sample of the sound thanks
Absolutely re-cap... After 30 years, I think its worth the few dollars to get another 30 years of good service. Leaving aome electrlytics that even test OK will have less life compared to the new ones probably leading to a reservice sooner than if all electrolytics had been replaced inuding the power supply caps. I also would replace the protection relay over cleaning the original every time. The dollar to reliability ratio makes it a simple decision to replace in almost all cases.
wow learned a lot watching this ... I picked up a 70's Kenwood KA 305 sounds decent but has a bad humm on tone selector knob ... and also more bass on one chanel , does that sound like more cleaning or replacing stuff ?
Hello from Meaford Ontario Canada, thank you so much good sir as I have always wanted to understand the reason for the orange capacitor s , low leakage and now I know and knowing is half the battle lol and I almost always use Elna Selnec 2 capacitors in my restorations and I was curious if you thought it was ok to use a Elna Selnec 2 capacitor in place of a power supply bi polar capacitor I have done so on a Technics SA 500 receiver and it works great however it seems like the unit is running hot ...or maybe that's by design. ..the sound is glorious as I even used new Nichicon Fine Gold capacitor s and filter caps the bi polar capacitor I replaced with the Elna Selnec 2 was a purple color can you explain those purple bi polar. ..thanks brother from your friend Scott in Canada
Have you connected your Wizard to a freq counter? Also remind folks to discharge all caps before testing. 👍
We want to see you recap
Tony, I hope that the smell of butyric acid in the morning is not a teaser for the apocalypse coming ;) Thanks for the video.
Tony, hopefully this is a simple question... When you are measuring the ESR would the ESR meter pick up resistance through your body if your skin is touching both of the capacitor leads? Of course I'm driving at effecting the ESR measurement. THX
How do you buy your components? As needed or just start picking different values in bulk qtys ???
what about the zero force faders what would you use on those as you do not want to get any friction or resistance with those faders ? thanks
It depends:
If you look inside and see no visible bulging, leaking, heat scorching, and then run frequency response tests and power tests, and if it runs quiet, I say leave them. Precautionary principal. You risk damaging something with an intervention.
How are the industrial capacitors listed when purchasing? Mouser shows different types, but not the BT
Hi, I have bought a 820 and has a really wobbly volume/balance control. How is it removed and could it be broken in transit, or just need tightening? Thanks, Colin.
I have been getting notifications that many of the Nichicon caps are being phased out. The UKL series that are low leakage are included. What will we use to replace those orange caps?
Most through-hole are close to obsolete in some or near future. Sadly.
SMD has taken over, and also for amplifiers where the smaller class.D is more and more used, and cheaper to manufacture
Cornell Dublier ( CDE) still makes a "CKH" and "CKE" line of low leakage caps ( orange wrapper, check the datasheet), they are listed on Digikey and Mouser as still being available as of 02/2023) I tried to link the datasheet here, but Tony didn't let it go through, but just search those and you should find them.
How did you get the knobs off the front?
Tony love your channel i have learned a lot from you,i have always been interested in electronics keep up the great work don’t change anything and don’t pay any attention to the hater’s
Automotive grade capacitors eh! Hmmmm sounds like something I need to invest in a lot more....
They might be expensive but at the end of the day, if I'm keeping that piece of equipment for as long as possible, then I don't care what it cost, I want it to last...
And I always go up in voltage, I believe that out of two identical capacity capacitors, the one that is rated for a higher voltage will tolerate higher temperatures and outlive the lower voltage one! They are physically larger as were the old wax paper capacitors, but you could put a higher voltage across the old wax paper capacitors than what they were rated for and they would survive, they were built to last which is why they can be found still working 60 years later, are we ever going to find a somewhat functional and factory original electrolytic capacitor inside a piece of 60 year old equipment one day in the future?
I would be surprised if someone did....
I have seen a video, it could have been made by RCA where they showed how they tested their capacitors and transformers in their TVs with Up to double the rated voltage!
As good as that automotive grade capacitor is, would it survive with double the voltage across it?
Who knows? Unless Tony feels like performing an experiment????? If they survive, check their values after to see if they got worse or improved... But I think that we would see capacitors exploding which is always fun to watch....
... 0r maybe computer grade caps rated for high frequencies. Look for "high temp hybrid polymer solid caps" from Panasonic or Nichicon...
Hey Tony, this 10/16v caps are marked on the schematics with black dots inside black circles. in the legend they are called low noise caps.
Yes, They are similar to the orange capacitors used in the Pioneer & Marantz gear. They all seem to fail in this same way.
@@xraytonyb thank you!
Have you ever done a side-by-side test in which you recapped one channel with different caps to the other channel (e.g. film vs elna)?
Having spent the past 18 years as an audio repair bench tech, I can tell you from experience that those lavender or lilac-colored capacitors are crap. Change them out. Don't bother to test them; just change them. They often become slightly electrically leaky ---- sometimes physically leaky as well ---- and can cause popping noise and minor DC offset, from the tone control section in particular (the fluid that leaks out of the capacitors is often corrosive, and probably conductive, and on those lilac caps I will often find that the negative lead of the capacitor is green with crusty corrosion). Also, any capacitors that are right next to a voltage-regulator heat sink, such as the black capacitor seen here that is tucked into the channel of an aluminum vertical heat sink in the power supply, should be changed. If it's located right next to a power resistor, change it. Heat is the enemy of electrolytic capacitors.
i recapped a Yamaha from the early 80s (high end pre amp) and about half of the lilac/violet caps leaked and were corroded / absolutely dead. i dont like seeing these either. later elna and nichicon in kenwoods have been Solid for me, no Leaks.
@@sgredsch , a lot of small orange caps from that era are shitty as well. They don't usually physicaly leak, but they become noisy or electrically leaky, and the ones that are sealed with epoxy on the underside instead of a rubber plug are particularly likely to fail, especially if located near something hot.
Wurth caps ? I'm about to do my first recap . I won't buy them if those are the ones you're referring to ?
@@ericschulze5641 , I've never actually seen any Wurth capacitors. Supposedly a German company and of a reasonable quality. The repair shop I used to work for used mostly Panasonic as electrolytic capacitor replacements, or Nichicons on occasion. The Panasonics are excellent quality, though perhaps more expensive than the Wurth caps. As for what brand and type of capacitor to use for a given replacement application, it really depends on the product, the voltages it runs at, the circuit design, and what was in there originally and whether that was the best choice for that application or not ---- which obviously I can't answer for you.
I don't really remember what brands those old lilac or orange caps I referred to were. I can tell you for certain that if you encounter any caps branded "Shoei", they're absolute garbage.
There are also cases where a product might have originally used relatively low value electrolytics which could instead be replaced by more reliable and higher quality film caps, typically when you have low microfarad values like a couple of microfarad at most and less than 50 volt, usually you can get film caps that are small and will fit comfortably in those locations. Especially smart to do so in critical locations like phono preamp circuits and tone controls, where even a tiny bit of (electrical) leakage taking place inside an electrolytic capacitor can cause a lot of noise and poor performance. Modern electrolyrics are usually much lower leakage than the ones that were used 40 or 50 years ago, but film caps will typically be even lower leakage by orders of magnitude. (We're talking about electrical leakage, minute DC currents passing through the capacitor, and not physical leakage; electrical leakage can show up as crackling and static and popping noises, especially when you rotate tone or volume controls).
@goodun2974 thank you, I have a couple other questions if you would. . . I plan on ordering this weekend around 60 caps / mouser I'm trying to use 105c over 85c as recommended by another utuber JDW. . . anyway nichicon & Panasonic caps all seem to be 85c & rated at 1000 hrs vs worth, rubycon,united chemicon at 105c & 4000 hrs & they're cheaper my question is does a higher ripple mean a lower esr & should I be trying to have them all of similar or same ripple or doesn't it matter ? it's looking like I have to get multiple brands to recap my old recievers in order to get similar sizes "physically " and similar lead spacing I'm not seeing nichicon this and nichicon that Panasonic this and Panasonic that I'm seeing is what they offer in the uf and voltage. I'm requesting, from various mfrs, then I try and get something that fits am I doing something wrong ? And again will it matter if 1 group of caps have a ripple of 18 another at 36 ? ect first recap will be a jvc cheapie then my technics then my Yamaha, then my Kenwood then my onkyo then my Marantz all as my skills and knowledge grow (I do have an extensive background in appliance repair 30 yrs. so I'm not completely new to this ) THANKS AGAIN
Your explanation on why 100kHz for in circuit ESR meters is wrong. Has not to do with surrounding circuitry interaction avoidance. For that matter these testers simply use small amplitude signals less than Vbe. 100kHz is the frequency commonly used by the industry for listing ESR spec. Because its conventionally high enough to overcome the capacitive reactance of electrolytics. So what remains to be read is ESR which is mostly non reactive.
You are absolutely correct. My description about the ESR meter was not so good. Thank you for the correction and for the much better description. This is how we learn from one another.
Best regards :)
Matsushita - Triangle cap :)
How do you reform a cap?
should i buy this meter LEADER LCR-740 METER
Love these Yamahas. Good times. Well before the bafoonery that is Home Theater. Where music was king.
I agree, surround sound really killed audio
Hi Tony, the Nichicon gold that tested bad is quiet small, was wondering if the physical characteristic of the capacitor has something to do with it.
Far as I can tell, capacitance is affected by the Area of the plates inside.
Also, I think what mostly matters to audio electronics are frequencies between 20-20000 hz audible frequencies, and testing beyond those frequencies doesn't give anymore useful information apart from capacitance drop significantly at those frequencies.
One reason I don't recap is that older capacitors tend to be bigger and has a lot of breathing room for the plates inside.
For me it's still a no recap. For the reason that we can't hear frequencies anymore at those frequencies, and I'm thinking the old caps are designed as they were.
I don't get it ? The man just showed you the numbers, the factual evidence in the audible frequencies,,,
@@ekbanjosworld4926 tell me if you can hear frequencies above 20,000 hz and I'll believe you. That's factual.
Recap it - if at least 1 bad cap has been found there are most likely more - best to futureproof that aspect of the circuitry :)