Bad capacitors in a speaker crossover make a big difference

This Canton Fonum 251 speaker has no treble output at all, but the tweeter is fine...
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[@DrCassette]

UPDATE: Both speakers have now been successfully repaired by replacing a total of 4 bipolar capacitors. The effect of the bad bipolar capacitor in the filter network for the tweeter was demonstrated in this video. But also the bipolar capacitor in the filter network for the woofer was bad. The bass response improved drastically after the replacement capacitor was installed. Both speakers sound great now, as you would expect from Canton!

[@d.s.w7779]

Hi ive got a bunch of sony dsw 6ohm do you know of good crossover.

[@tallpaull9367]

Hopefully you put some 5.6uF caps on the tweeter instead of changing the value to 6.8uF. 5.6uF NPE crossover caps are easy to find. I would recommend Mundorf E-CAP PLAIN or Jantzen Premium Elko Smooth. Mundorf RAW or Jantzen Elecap if you want to keep it cheap, or just use these on the LF woofer...

[@DrCassette]

@@tallpaull9367 Nope, the owner of the speakers wanted to have them repaired as cheaply as possible. He is not into HiFi, so he probably wouldn't notice any difference anyways.

[@Poppinwheeeeellllllieeeeez]

This is a very good video. Thanks for sharing.

[@MF-le7fp]

I AM into HiFi, but at this late date, I probably wouldn’t notice a difference either. I blame the 1980s, Billy Idol, Harman Kardon, and Cerwin Vega for all of this. Vega’s AT-15s should have come with warning stickers over the speaker terminals. NOTICE: Listening at high volume for extended periods of time may cause cheap replacement crossovers to sound wonderful 35 years from now. 😂

[@robertdavis5714]

Well done Sir. Did not know a good capacitor will over-ride a bad capacitor for a quick diagnostics. Thanks for education.

[@jeffm2787]

Don't count on it.

[@noneofyourbusiness1603]

I had exactly same problem with a set of JBL control 1's I just repaired. One speaker had absolutely no treble whatsoever. Initial capacitance test on the treble cap showed that it was ok (with a traditional multimeter). However, I was still suspicious, I pulled the hot melt glue off the part and desoldered it from the pcb (it was hidden in the middle of the big treble inductor coil!). The top of the cap was fine but the case was slightly bulged out. Put my LCR meter on it, at low freq (100hz) the cap reading was fine, as soon as you adjusted the LCR to high frequency (10khz or above) the value drastically dropped from 3uf to about 200nF! Comparing this to a good cap, the value stayed roughly the same with any freq. I learned a lot from this repair 😇

[@DrCassette]

Interesting, thanks for sharing what you found out :)

[@davidjudd951]

That's actually very good troubleshooting on your behalf. I know seasoned techs. that wouldn't use that level of troubleshooting.

[@kcMan7938]

Proper testing and diagnosis is key to any repair . Well explained and shown here in this video .

[@DrCassette]

Thank you :)

[@RollinRagu]

I have changed capacitors in several older speakers. I've never noticed a huge difference. Likely they didn't really need to be changed. I just picked up a pair of Polk Audio Monitor 10's from 1990. They perform well, but have anemic bass. Your video gives me hope that the capacitor can make a tremendous difference in cases. I will have to begin investigating. Thank you.

[@yvesboutin5604]

Very good presentation! As you suspected, if driven to party level, the weakest link in the chain fails. As an electronic technician, I change electrolytic capacitors on a daily basis. The electrolyte leak out over time, so their lifespan is limited and when excessive power pass through them, it shorten that lifespan even more.

[@mauanderuk]

I usually replace these with polyester types as they perform much better, also the ferrofluid goes hard in the tweeters and replacing the fluid makes a lot of difference. Generally like you I only replace caps if they are faulty. Many thanks for the videos.

[@MatijaVabec]

I had 1987 Canton speakers, caps were just fine. I have 1976 Philips' now, caps are just fine. So yeah, caps are not always faulty like a lot of people think. This one, unfortunately was.

[@prestonashworthmusic]

I've pulled out the amp for a powered speaker that lost high frequencies and the tweet tested out fine and a know good tweet also didn't work. I got the schematics from Harbinger (vari 2315) and between that and a study of the board I identified the inductor and capacitor on the high frequency output for the board. Oddly both tested out but this video is going to have me give it a second look. I found the white paper for the IC that runs this class D amp and am hoping it isn't something upstream from there as there are a gajillion components. I'm a systems engineer by trade (with a past life in audio engineering) so this is a bit out of my wheelhouse and I'm grateful for the video.

[@enricoself2256]

I agree with your rant against blind recapping as a cure for every electronic problem ... Indeed the opposite, recapping is stressful for the boards especially if caps have bent pins to keep them still while they were originally soldered. Unless a cap is leaky or dead short, it is usually best to leave it as it is. Electrolytic caps are used mostly as filters for IC supplies and even if they have only 50% of rated capacity, it is not such a big deal.

[@DrCassette]

I should add, in the case of analog electronics there are coupling capacitors in the signal path. If they are too far out of tolerance, they will have an unwanted influence on the signal, so if a piece of audio equipment does not sound as good as it should, if the signal is quiet or the frequency response is limited, coupling capacitors should be checked.

[@westelaudio943]

@@DrCassette I always change audio output coupling caps. Don't want DC in a speaker coil from a shorted cap. For everything else, change only when necessary.

[@OldSonyMan]

I recently bought a pair of Sony APM-22es mk11 s for a very low price, which was justified because of the state that they were in ! The tweeter surrounds were not fitted correctly and each had two corners cut off ! And they were held in using Wood Screws (some at crazy angles !). Having removed all the components from the two cabinets, I discovered that the whole of the wiring had been replaced and the crossover had been worked on. I have tested the resistance of the 4 speakers and all seems fine (at 6ohms for the woofers and 5.2ohms for the tweeters) However I am a bit stuck on the crossovers as I don't know what I am supposed to test, hence this video has been helpful and I will be having a go as soon as I obtain a component tester and can 'copy you'. Thank you for this video 🙂

[@d.s.w7779]

Hi ive got a bunch of sony dsw 6ohm do you know of good crossover.

[@SpeakerFreak95]

A worthy upgrade to consider, replacing the NP electrolytics with equal or close value film caps, on the tweeter side. Electrolytics for the low pass function can be electrolytics with no issue. I’m not sure if it’s a placebo effect, but my ears usually prefer film caps in high pass and band pass applications, when listening closely.

[@DrCassette]

Electrolytic capacitors indeed are not ideal, I once accidentally replaced film capacitors that looked like old electrolytic capacitors with new electrolytic capacitors and the speakers sounded noticeably worse. However, I don't think the owner of these speakers would really notice the difference, he is not that much into HiFi.

[@DeadKoby]

I am guilty of going "cap crazy" replacing all electrolytic caps in certain situations. In some devices, the TIME and DIFFICULTY to disassemble the unit and get the boards out is so much, that "going overboard" is a method of preventing having to go back again any time soon.

[@DrCassette]

That is a very valid point, some equipment is ridiculously difficult to disassemble...

[@Ingleseeuu]

Highly informative. Thanks a million!

[@DrCassette]

You are welcome :)

[@uzyh7622]

Cross-over that is built for 4 ohms. If I lower the resistance of the speakers, what happens to the frequency cut-off points?

[@rogerchurch3804]

a lot of people dont think of checking caps when restoring or repairing speaker crossovers especially when spkrs are 20 30years old driven at high power levels can damage caps also .

[@stephenbrobbey4873]

I'm sorry to reply on this video late. I have accoustic research ps2062, made in 2001. Sometimes, one of the speakers tweeter stops working. In order to find out,if the amp was the culprit, I swapped the channel and the problem was still persisting in that speaker. I cleaned the speaker terminal, but still not working. I disconnected the speakers wire from the amplifiers terminal and connected the wire to a 9volt battery and it woke the tweeter up and everything was working fine, but in a week or two, the tweeter stops working again and I have to connect the speaker wire to a 9volt battery to get it working again. Could that be a capacitor problem? Kindly help me. Thank you

[@karlharrison2449]

Great vid. Cheers.

[@edwardautrey3671]

Well done Dr.

[@DrCassette]

Thank you :)

[@Plumbumas]

Maybe its possible to check crossover without special tools with only multimeter?

[@WT-ic8mv]

I wander if you can help me,I been trying to recap my speakers crossover ,I can seen to find anywhere this capacitor made by spirit 106J 100v and also spirit 275J 250V any ideas ? I’ll appreciate and new in this ,thanks

[@mcweb1036]

Thanks !!!

[@pauledwards2817]

Humm, an interesting subject for a video. It never crossed my mind about crossovers. I still use a pair of speakers I purchased 35 years ago... About all I can say is that they both are still a good match and I am well aware that I can't hear so well in my late 50s. No one seems to mention cross overs getting old, it's mostly re-cone work and that's about it, or perhaps making a superior crossover.

[@DrCassette]

Bad capacitors in speaker crossovers are certainly a very uncommon problem, this is the first time I came across such a problem. So if the speakers sound fine, there is no need to worry about capacitors in the crossover...

[@pauledwards2817]

@@DrCassette thank you. As always fascinating content.

[@RCALivingStereo]

When you put new cap across those leads, was the old one still hooked to to ? I have a older Rca speaker from 1957 I’m wondering if mine should be changed

[@DrCassette]

If the old capacitor is open, there is no need to desolder it, you can just put another capacitor across it for a quick test. Of course for the final repair the original capacitor has to come out.

[@JCKCPA]

Excellent video!

[@DrCassette]

Thank you! :)

[@jeffm2787]

Let us not forget the Capacitor plague starting in the late 90's. Greed gone wrong. My mentality on capacitors is always suspect them first. Having repaired hundreds of devices I've found capacitors to be the problem or related to the problem most of the time. I don't however just bulk replace. Matter of fact you can sometimes cause problems by doing so as some of the characteristics of older caps were part of the circuit design. i.e. tossing in a lower ESR cap is not always better.

[@DrCassette]

Yes, of course there was also the capacitor plague of the late 90s and early 2000s, but these speakers were made before that happened, so I didn't mention it.

[@gino3286]

Hi very helpful video There are companies selling upgraded crossovers for some commercial speakers I think that xover can make a huge difference I would use the best parts possible in series with the drivers

[@petermulka3085]

So do you have to disconnect one side to test a capacitor or can you do or while it still connected to the board?

[@DrCassette]

Ideally you disconnect a capacitor from its circuit on one side before measuring it

[@user-tv3nu8zs3s]

For better sound install an auxiliar 2,2uf.

[@issactian3143]

Why is that 2 types of capacitors used in serial ???

[@kvikkisch]

I have the same problem with my Canton speakers, but I can really not find a place where I can buy the correct capacitor with the correct Vca. Do you have any tip on where to buy ???

[@robobin]

mouser or ddigikey

[@meowme7644]

schönes video.👍 instantly subbed ☺😉 first i just wanted to see this Transistor tester 😁

[@DrCassette]

Thank you :)

[@Clint_the_Audio-Photo_Guy]

So put a poly-cap in it and be done with it. That speaker probably doesn't deserve a Film Oil cap, but might as well upgrade from a junk electrolytic cap while you've got it open.

[@sachavilleneuve6688]

Hi ! So I upgraded the capacitors in my 30 yo B&W DM640, w/Solen PP caps, and they became too bright! I really miss the smooth relaxed voice they had previously. What would you recommend?

[@DrCassette]

Put the original capacitors back into the crossovers. That's what I did when I ran into a similar situation with a pair of KEF Coda speakers.

[@sachavilleneuve6688]

@@DrCassette they are mostly unusable now, would you recommend to buy new electrolytics?

[@DrCassette]

If the original capacitors can not be used anymore, you don't have any other choice but to keep experimenting with different capacitors until you find a set that sounds good...

[@THOMMGB]

You could contact the B&W parts department and buy replacement capacitors from them. Or, maybe talk to tech support and ask their advice on what kind of replacement capacitors to buy.

[@security-don]

👍 My 1104 exploded. 5.6 microfarads 40 volts. jensen. Fonum 530

[@thomasschafer7268]

To change the capacitor is the one Problem. The other one is the positioning of the inductors. One should be in upride Position. So the magnet fields of the inductors influence the signal.👍👍🇩🇪

[@fins59]

Sounds a bit woo woo, please explain.

[@crt0512]

capacitor gone bad diode gone wild 😆

[@bhanukishore9360]

is this a sealed enclosure ?

[@DrCassette]

Yes, this is a sealed enclosure.

[@huckietam6746]

Measuring the DC resistance of a tweeter may not tell if the tweeter has been partially damaged. I felt something is not right about one of my tweeters. The DC resistance measure the same of both tweeters. It is only I use a Dat2 to measure the speaker parameters such as Fs, Qts ...etc that there is a huge huge difference between the two. That is when I know one of them has been damaged. But it is not shorted.

[@DrCassette]

Measuring the DC resistance will generally give you a pretty good idea if there is something badly wrong with the tweeter, it's a good first test

[@huckietam6746]

@@DrCassette This is not just good but the necessary first test. It can tell you if it is short. But for those units especially to be played in high decibel, you also need to know if they are playing in their acceptable parameters. For that you need more than a multi-meter. Equipment like the Dat2 or Dats v3 are very cheap in the modern days.

[@trevorcourt1403]

thats the same problem i have with cap

[@craigpenfold4653]

Does the voltage matter? Can I put a higher voltage in place?

[@DrCassette]

Yes, the voltage rating must be the same or higher than the original.

[@craigpenfold4653]

@@DrCassette thank you

[@onesixfive]

I’d like to meet certain people in a dark alley.

[@disorderindminor]

the IBM mainframe computers the military used for our radar installations in the 70's and 80's required to be recapped every 20 years even if in storage becasue electrolytic capacitors leak over time as the rubber seals fail plain and simple. You ever open up an old piece of electronic gears and smell it you'll smell that smell like if you cut open a cap. The people who replace all caps don't want some old marginal cap failing when they have paying live shows. Polyester caps are pretty imortal but aren't always in useful values or ESR which is another thing to keep in mind with old caps it can seem perfectly fine but the ESR is frequency-dependent, temperature-dependent, and changes as components age...

[@DrCassette]

Yes, people who enjoy replacing capacitors always have plenty of reasons for why it is totally necessary...

[@crossoverchef]

good

[@dejv1984]

can I measure the capacitors directly on the crossover, or do I have to solder them out of the crossover, please? of course I will discharge them before measuring by connecting both ends together. thank you

[@DrCassette]

Generally it is better to measure capacitors out of circuit, so desolder them, if possible

[@davidjudd951]

The only capacitors to worry about discharging, are usually in AC, and most certainly High voltage AC, such as three phase. And older televisions. Typically the capacitors in a hi-fi crossover wouldn't need discharged.

[@GIBKEL]

Night and day….

[@westelaudio943]

Considering a speaker crossover is a pretty benign environment for a cap, this speaker doesn't look old enough (late 1980s? 1990s?) for a good cap to be that worn. Either those caps are crap or they have a ton of hours on them, and were often operated at high power.

[@westelaudio943]

I think I actually have the same speakers, from 1992 I think.

[@westelaudio943]

Ok you mentioned it later anyways, lol.

[@DrCassette]

The capacitors indicate that they are from 1992, however the design of these capacitors dates back to the 1970s. Maybe that explains the relatively short lifetime.

[@pagepro211]

what's the point of your comment? yes, the cap could be faulty or a bad design but it could be actually a good cap but the speaker was blasted for hours which caused the cap to die.... either way the cap is bad and need to be replaced.

[@westelaudio943]

@@pagepro211 If it was overpowered I'd rather expect the delicate tweeter coil to be blown, not the cap. It's still a bit strange that it failed completely open after just 30 years.

[@banginghats2]

Strange the way the capacitance has gone up rather than down.

[@hdrperformance2719]

Yes this is normal in canton. Capicators loosing ESR then uF go Up

[@dougtaylor7724]

I have found many speakers had very poor quality electronics used in the cross overs. My thinking is they felt cheap and middle of the road speakers would have a cone failure and be tossed after 10-15 years. Why make cross overs that last 40 years.

[@DrCassette]

I too have noticed some speakers contain rather dubious electronic components. Maybe some manufacturers who only produce speakers and no other types of electronics have difficulties sourcing good quality electronic components because they don't need them in very large quantities and therefore are not in a very good position when negotiating with suppliers... Also they won't have their own quality control for the electronic components that they are supplied with. There is certainly a difference when your product contains 2 capacitors vs. when your product contains 100 capacitors. The capacitors in this Canton speaker indicate that they are from 1992, but they look like they had been made like that since the 1970s without any changes.

[@dougtaylor7724]

When you said they were made in 92 in the video, I was thinking those were 70’s era parts. Can’t remember where I saw similar parts, but it would be in pre-1980 pieces. You may be on to something there.

[@rickysnit2163]

3:11 yes! It's a mental condition, I'm convinced..

[@rickysnit2163]

But.. That said, everything on that crossover is poor quality.

[@qddk9545]

It is not that difficult, just put in a 5.6 uF plastic cap, and of you go. And maybe change the other one also when you have the speaker opened.

[@pixelreflectorpro]

If you really want to improve it you'll need to do more than that

[@darthbubba866]

I don't recommend "shotgun" capacitor replacement as a standard practice, but when someone brings around a 40+ year old vacuum tube amp I start thinking about the power supply electrolytics becoming a hazard in the near future. That and the coupling capacitors feeding the output tubes unless they are of superior quality.

[@ThisGuyFrritz]

It sounds like we may have to wait for a follow-up video.... IF the speaker owner EVER replies.

[@DrCassette]

The owner of the speaker is a friend, he replied not long after I finished this video. I will replace all capacitors in both speakers. That probably won't be too interesting, given that the diagnosis of the problem is already done. So there most likely won't be a follow-up video...

[@ThisGuyFrritz]

@@DrCassette So, whoever is curious would have to read your reply so they would know. Meanwhile, I suppose we're gonna see what's your next interesting video.

[@favouritetree6286]

hahahahaha, totally agree,

[@dobermanguy9437]

This shows you right here how important it is to test capacitors and learn how to read a meter correctly like this guy said the Tweeter was not bad but the capacitor was but some people will say oh the tweeters bad without even testing testing the capacitor because most likely they don't know how to test the capacitor great video we all just learned something

[@davidjudd951]

Unfortunately, most just don't have the CAPACITY.

[@heromail2903]

Bad capacitors. Bad has two meaning: 1. Damaged capacitors, or 3. Low quality capacitors. Which one?

[@jimb032]

I thought the rant was going to be for the ones that were going to say that now you need to replace the same capacitor in the other speaker otherwise it will not be balanced properly anymore. Lol. You forgot this crowd!

[@svenschwingel8632]

Actually, serial capacitors in a crossover network's high pass filter do have a huge impact on sound quality, not necessarily in frequency response but rather in step response. And given that both caps for both speakers are equally old with an equal history of usage, it would indeed be best to replace both with the same type. And while you're at it, it also doesn't hurt to check the ferrofluid in both tweeters. Then again, it all depends on what the owner is using these bookshelf speakers for. The Canton Fonum series was well-acclaimed back then in the early 90s 🤷🏼‍♂️

[@DrCassette]

I don't totally disagree with those who say that both channels should be kept equal. Certainly if a modification should be necessary in one channel, the other channel should be modified accordingly. In the case of these speakers, the other one which my friend has not given me yet has the same problem of no treble output, and since these speakers were likely made on the same day from the same batch of components, and given that they were used as a pair, being exposed to the same conditions throughout their life, I think it's safe to say the other speaker is going to have the same fault, bad capacitors in the crossover. And even if the other speaker was fine, since I have to order the replacement capacitors anyway, I would still replace all capacitors also in the other speaker, just to be on the safe side.

[@bhanukishore9360]

i have a Surround Speakers - i can hear Sound from Tweeter but no sound from Mid range. When i checked Mid range speaker with amp meter its not showing any ohms. another pair is like same but i can hear little crackle sound from Mid range, when i checked ohms its showing 6.8ohms for 8ohms Impedence My question is Crossover problem or Midrange driver problem please let me know

[@DrCassette]

Seems like one midrange speaker is blown, and the other one that just crackles is almost blown (voice coil partially melted). You will have to replace all these midrange speakers.

[@bhanukishore9360]

@@DrCassette so crossover will be fine ???

[@DrCassette]

Yes, the crossover should be fine.

[@PeterMilanovski]

Your component tester is only showing you the capacity and ESR readings... It doesn't show you it's parallel resistance! I would love to see you take this bad Capacitor and put DC across it and measure how much DC leakage current it's passing.... Technically, it's should only pass DC current until it is charging to it's rated voltage and then stop, everyone just looks at the ESR measurement... But don't know about it's Equivalent Parallel Resistance... This is why I always say that an LCR Bridge Meter which can give all Capacitor measurements is a very important tool... The only reason why a Capacitor should show up more capacity than what it's rated for is if it's leaking DC current, the tester takes longer to read which makes it think that it's a larger value than what it is... So if you can set up a DC leakage test... I would totally watch that video... Well actually I will watch whatever you post anyway because I really appreciate what you do... Capacitors are a never ending topic... That's why Mr Carlson's Lab developed his own capacitor tester for Equivalent Parallel Resistance... It's the measurement that really matters! High ESR capacitors are only really bad for use in power supplies... A series resistor in a Capacitor has difficulty filtering out DC ripple, it's parallel resistance that destroys everything else! I'm only trying to be helpful... Besides, what do I know LoL.. your the expert here!

[@benbaselet2026]

Well he did kind of test for leakage because that's exactly what the excessive "Farad" rating is that the tester shows. He just didn't mention it that way.

[@pagepro211]

wtf, the capacitor has a rating printed on the exterior, he checked the values of those ratings with a meter and it failed.. wtf are you talking about.. the system is design for those ratings and the cap is out of spec. simple!

[@edwardbalboa5528]

Cap is the FIRST thing you check .... All tweeters have a cap in series

[@DrCassette]

Capacitors in speaker crossovers don't normally go bad.

[@thomasschafer7268]

I hope you replaced it with mkp 400v types.🤔🤔🤔🤔

[@arwlyx]

Okay I'm not sure I understand the rant? You say recapping is bad but then prove that the capacitor was the problem and that bypassing the bad cap with a working one fixes the issue? Unless you mean people are just going for recaps instead of troubleshooting to find that the problem is the capacitor (which is very odd but not really controversial to say its wrong, but in this case, regardless of their first plan of action being right or wrong, would fix the problem), I'm unsure what you were trying to hint at, sorry.

[@jimb032]

He didn't say doing it was "bad", he was merely saying that there are going to be people that say he needs to just blind replace all of them. Those people are generally idiots, blind replacing all with ones that will never last as long as the ones left in would or be less of a tolerance.

[@arwlyx]

@@jimb032 But in this case it would technically fix the issue, no?

[@jimb032]

@@arwlyx Yes, if you can call that "fixing". I call it throwing the baby out with the bathwater. To compare it to a car: You buy a new car with top of the line tires, these tires are guaranteed for 80k miles and have a 150mph speed rating. One day you run over a nail and one tire experiences a flat- but all tires have 3/4 their tread life still. You trash all tires and replace them with a set of MayPops with no guarantee and a spped rating of 80. You fixed the problem, in a stupid way, but you fixed the problem.

[@genericdude6551]

Loss of treble could be due to hearing loss.