Replacement capacitors exploding

Generally speaking: a cap will be used to roll off a woofer at a steeper rate (ie: 12dB/oct), going to ground, between a series connected inductor and the woofer.       I’d say you’re clipping your monitor amps, but- that usually will take out the tweeters first.       Try doubling (at least) the rated voltage of the caps, keeping capacitance the same as the original.       If you can afford them (high voltage/high capacitance can get salty): try metal film caps, rather than electrolytics.           Whatever you do; be certain the caps are non-polarized.          Higher capacitance values can be reached, by paralleling caps, which may be a less expensive way to afford metal films (ie: Metalized Mylars).      Paralleling caps DOES NOT increase the power handling (voltage rating).  

I had a similar problem at work.  The caps would just open.  They looked to be electrolytic, just physically much smaller.  When I opened one up, it was hollow with a tiny chip inside!  

The voltage rating is too low. Poor quality capacitors. Replacement caps installed are not Non-Polarized.

Upon closer examination, the old capacitors say NP and the new ones say BP.

I’ve been searching for non-polarized capacitors and I have found three different sites where the item description says non-polarized capacitor and then the photo is of a capacitor with BP written on it, not NP What is that about?

BP should mean Bi-Polar. They SHOULD be the same... Try to find Non-Polar, think the last time I bought some NP caps was on Mouser Electronics. I'll check later to see if they are NP or BP. What are the voltage ratings of the new caps and what brand?

What is the value and voltage rating on the caps?
Also,  I suspect that you have an DC Offset issue with the amp being used. 

What construction/ "lytics? Film? What? Where did you get them?

I ask because there is TON of fake stuff coming out of China, especially on ebay, that is just crap. Rated 100V, fails to 60. I got some others that leaked like a sieve when i tested them.
Its very sad, but you need to get stuff from very reputable sources.

You did not mention the type, rating etc. Not to condescend, but are you familiar with all the rating components, and with all the various types of capacitors and their pluses and minuses? It gets pretty arcane quickly. Get all the data, c’mon back and happy to help.

In almost all speaker crossovers you want film types. Film cannot explode.Electrolytic, which would be smaller, are polarized and cannot work that environment. They would be reverse polarized (sometimes) and almost certainly fail.

I’m convincing myself you did this. Get some expert advice since they are also awful audio caps - very nonlinear, and have a short life. Films (which were likely in there) will last (i kid you not) 100 years.

G

@itsjustme-  It's comical that you'd say something like, "....  are you familiar with all the rating components, and with all the various types of capacitors and their pluses and minuses? It gets pretty arcane quickly." and then assert, " Electrolytic, which would be smaller, are polarized and cannot work that environment. They would be reverse polarized (sometimes) and almost certainly fail."      fyi: Bipolar electrolytics have been used in countless speaker systems, from the very beginnings of audio.                                    When I was in the electronic repair/speaker reconing business, I lost count of the systems that came through the door, with just one bipolar electrolytic, meant to block lows from the tweeter.     Perhaps another, higher uF value, if there was a midrange driver.      Junk, but still........

Are you sure you are using bipolar caps??

Oh, i see he did later clarify that it was in fact a BP/NP. 
Bipolar and Non Polarized are functionally identical.
So if the voltage rating was the same it ought to work.
That said, i would never want a Bipolar electrolytic where i could have a film cap. The film may be much larger, but will be far more linear and better sounding, and more reliable (like within its rating, pretty much forever). In fact i have some large value films, very old, depending on the value you need. I was trying to give them away without success some time back.

oh and to someones point a DC offset might have an impact on a NP cap (if its big enough) but not on a film.
Which brings up an interesting theory on how it failed originally - if in fact you have enough DC (easy to measure) a BP cap, which is designed for AC on a small, ideally zero, DC base (need the spec sheet for more) could have failed.  And the replacement.
Putting in a film would stop that failure but not the DC offset - which is likely  applied to your woofer BTW.

Examples of electrolytics, specifically for crossovers: (https://theaudiocrafts.com/x-over-parts/audio-grade-capacitors/bennic-non-polar-electrolytic-capacit...)   and:  (https://theaudiocrafts.com/x-over-parts/audio-grade-capacitors/panasonic-bipolar-andquot-for-audio-c...)          For a large selection of quality crossover capacitors, these guys are a go-to:  (https://www.madisoundspeakerstore.com/capacitors/)

rodman99999 - Thanks for the link to Madisound, good info to have around. itsjustme - Not so good...

For best performance and long term reliability, crossover caps MUST be NON polar FILM capacitors PERIOD.

You should NEVER use electrolytic capacitors for that purpose (well, they may be kludged back to back but forget it). Furthermore, you should pick ones with the highest voltage rating that you can find, since they are subject to AC voltages in the crossover. You can NEVER go wrong with higher voltage ratings. Buy the HIGHEST voltage rated version that you can find. They will be more expensive, but you will sleep better.

If you have accidentally used electrolytics, they will blow almost immediately.

Here are some excellent examples:

https://www.partsconnexion.com/Jantzen-film-caps.html

The silver ones are rated up to 1200 VDC, which is probably ok for about  up to 300VAC, which is more than any power amplifier can ever put out and they will outlast your house.

If you go with a high voltage higher quality cap of the same value you will have no problems but they will be expensive try a solen cap of the same value they are not too expensive and they will outperform the originals.

BTW….

NP/BP electrolytics are super easy to make. They are just polarized electrolytics mounted back-to-back. The cans are connected together. But the capacitance value is halved. For instance, 2 1000 uF polarized caps can-connected makes a 500 uF NP cap. The voltage rating stays the same for both. Not rocket science here, folks!

More bang for your buck?

Might want to call Crites speakers in Arkansas, specializes in Klipsch rehab.

@rodman99999, is absolutely correct. I have only one thing to add. It is important for imaging that both speakers in a stereo pair have a frequency response curve that is as close to being the same as possible. Without the equipment to tune crossovers and speakers it is probably best to stick to the tightest tolerances you can find in caps, coils and resistors. Don't worry about the brand. Worry about the tolerances (the lowest % error.) This will cost a little more. Unfortunately, even if your speakers have exactly the same frequency response curve the room will play havoc with it. Symmetry is always best.

Forgot. Someone mentioned DC offset. Two things will destroy speakers actually three things if you include idiots like me, DC on the amplifier's output and clipping amps. 

Another great place to get parts is HiFiCollective. Check out their web site!

If one took the time to view these pics of Klipsch stage monitor crossovers, they’d note that the OEM/factory caps, comprising the LF circuits, are bipolar electrolytics.    (https://www.ebay.com/itm/Klipsch-Type-KSM-2-Crossover-/392714043491)       (https://picclick.com/3-Three-JBL-S3HC-Klipsch-KSM-15-and-Klipsch-231960707452.html#&gid=1&pi...)       (https://picclick.com/3-Three-JBL-S3HC-Klipsch-KSM-15-and-Klipsch-231960707452.html#&gid=1&pi...)        This last link contains a crappy pic of the KSM-1 crossover. The silver can at the bottom, should the stock electrolytic, in the LF section, that gave the OP his initial problems.  Scroll right and it's third from the last pic: (https://reverb.com/item/13889916-klipsch-ksm-1-vintage-15-2-way-floor-monotors-with-phenolic-diaphra...)      If Klipsch provided him with new, replacement crossovers, they’d probably still come with electrolytics, in that position.        I've hated electrolytics, in crossovers, from day one of my experience with electronics.    The electrolytes will dry out and the cap will lose it's values.   Over-voltage will cause the electrolytes to expand and explode the cans.       BUT: they've been used, for the sake of economics and availability, by speaker system manufacturers, since the beginnings of audio.      

These folks have some wonderful product:

https://www.partsconnexion.com

as do these guys:

https://solen.ca

As has been said above, electrolytic caps have been used since the dawn of time in crossovers. If they are being used in speakers currently, it’s as a cost cutting measure. High voltage film caps are the way to go as has been stated also. 

To replace any cap, know more about the cap you are replacing... the methods of both manufacturing and usage have changed. Also, many new types are available now.
As I don't have the time or space to discuss the above limitations, I will give some advice instead. First, ALWAYS buy your caps from a REPUTABLE DEALER, not the local parts store. Second, ALWAYS use replacements with a higher voltage rating to prevent problems. For example, if a filter cap is rated at 450 volts DC, use a 630 volt cap. If you don't know beans about caps, DON'T TOUCH YOUR PRODUCT and find an expert. The types of cap DO make a difference!

Only true about higher voltage in some applications, like this one. Not true for DC supply voltage filtering!

Is there a way for me to order capacitors with the same specs printed on them that are also heavier duty in some other way?


~~~~~~
Get the Mundorf EVO silver/gold or SESGO which are 2x's the price, but worth it. 
Built to last forever. Sonically, 2nd to none. But as i say, they are pricey. 

As the saying goes, " If it ain’t broke, Don’t fix it".....for example, my cassette deck is on its 38th year, never been touched, except a belt change. It plays like day one...

Hello James Sheyser!  For pity' sake, replace those caps with something much better. Use a Mundorf KPF. They are rated at 250 volts and will larger that what they are replacing. Be sure the "mfd" number is the same as those you are replacing. The old ones are probably between 50 and 500 mfd. A good source is PartsConnexion in Canada. Check out their website. They are not cheap but they will not give you any trouble. Good Luck!

caps in series

http://wiki.ece.rose-hulman.edu/herniter/images/0/03/Aluminum-Electrolytic_Capacitor_Application_Gui...

NON-POLAR
If two, same-value, aluminum electrolytic capacitors are connected in series, back-to-back with the positive terminals or the negative terminals connected, the resulting single capacitor is a non-polar capacitor equal in capacitance to either of the original pair. The two capacitors rectify the applied voltage and act as if they had been bypassed by diodes. When voltage is applied, the correct-polarity capacitor gets the full voltage. On a capacitor meter with no bias voltage the two capacitors measure half capacitance as you expect form capacitors in series.

https://www.digikey.com/en/resources/conversion-calculators/conversion-calculator-series-and-paralle...

@imhififan

Although what you say works, the electrolytics will not have the lifetime of film capacitors. Their lifetime is in the 5-10,000 hours range at best, whereas the film capacitors' lifetimes are typically in the 50,000 hours range.

Please get film capacitors :-)

Also note that if the capacitors you buy are rated at a specific DC voltage, they will only be able to withstand about a third (theoretically about half (square root of 2) but I am being conservative) when exposed to AC voltage, which is what is inside the speaker.  So, get a film capacitor with highest possible voltage you can find.

If you have a 500 watt 8 ohm amp, the peak voltage across the capacitor may be up to 65 volts AC and may shoot up to 100 volts (approx power supply rail) during very heavy transients.  So, you would need a MINIMUM 300 V DC capacitor.  The higher the voltage rating, the less stressed it will be, which all adds up to longevity & reliability.

If you want to sleep better and not worry, pls do the above :-)

@cakyol,
I totally agree film cap is the better choice on speaker crossover, what confused me is if using two same-value aluminum electrolytic capacitors connected in series back-to-back, the capacitance is equal to either of the original pair or half?

@imhififan -   Half the capacitance.       https://electronics.stackexchange.com/questions/69715/can-two-electrolytic-capacitors-be-made-into-a...

I concur with rodman, half, I was mistaken about the same value in my previous post. Sorry for the confusion...

@rodman99999
Thank you for the link.

@fiesta75
No apology necessary, your earlier post lead me to these two document from cornell-dubilier and caused the confusion:
http://wiki.ece.rose-hulman.edu/herniter/images/0/03/Aluminum-Electrolytic_Capacitor_Application_Gui...

NON-POLAR
If two, same-value, aluminum electrolytic capacitors are connected in series, back-to-back with the positive terminals or the negative terminals connected, the resulting single capacitor is a non-polar capacitor equal in capacitance to either of the original pair.

http://web.archive.org/web/20131110001709/http://electrochem.cwru.edu/encycl/misc/c04-appguide.pdf

NON-POLAR
If two, same-value, aluminum electrolytic capacitors are connected in series, back-to-back with the positive terminals or the negative terminals connected, the resulting single capacitor is a non-polar capacitor with half the capacitance to either of the original pair.

Thanks for the clarification.

Newark/Digikey is an electronics supply chain for pros, if you know what you are looking for/need?

https://www.digikey.com/en/products

Cheers,

T eh

Many of us who frequent the Klipsch forum and work mostly on Klipsch often go to Parts Express for caps. Lots of non polar electrolytics out there but in general I replace them with poly caps even though they are much larger and may require two to get the right value.
What exactly did you replace the OEM caps with? Brand, type, UF+tolerance and voltage.
  I have rebuilt hundreds of Klipsch crossovers and never had your problem so I am also wondering how hard you are pushing them. I  bought a pair of KP-262's once that had melted the rectangular blue mylar caps but it took really serious abuse to get there. They still played but did not sound very good.

" rodman999995,010 posts06-10-2021 1:31am@imhififan - Half the capacitance. https://electronics.stackexchange.com/questions/69715/can-two-electrolytic-capacitors-be-made-into-a... " With all the non-polar caps out there I have no idea why anyone would do this. Now there is value in using two caps in parallel to get to the same value as one and that is the ESR will be reduced and low ESR is a good thing.

@mahlman-  "With all the non-polar caps out there I have no idea why anyone would do this."     Same here (makes no sense)!                                                                                                                I’ve never used an electrolytic in a crossover, even when repairing a customer’s.    NOR: would recommend using anything but, at minimum, metalized mylars.    Preferably: one of the better metal films.                                                                                        "Now there is value in using two caps in parallel to get to the same value as one and that is the ESR will be reduced and low ESR is a good thing."    Absolutely/all day long!                                                                                                                                                                             That post was simply an answer to a posed question.

@jamesheyser - Are you still there? Any more info on brand, voltage or capacitance? 

Bryston Amps and electronics as well as Axiom Audio both use Clarity Caps as does Whest Audio in London.  These three very high end producers of sound equipment using these caps says a lot to me and I'd be looking at Clarity Capacitors out of England for really top notch quality and high tolerance components.   They are hand made and tested, very stable and worth the extra cost.... as in expensive!

I absolutely agree about Clarity caps, they are excellent. I'm not sure the benefit would justify the cost for "stage monitors", but that's up to him. I personally haven't use caps in my home speakers in many years as I like active crossovers so much better. Silver plated copper for me.

     ClarityCap makes excellent capacitors.

     Matter of fact: I have four ESA25, 250V and two ESA 50, 250V caps looking for a home. Also: two Mundorf, CFC14 (14Ga), .46 Ohm, 2.7 mH, air core inductors, looking for a good home (someone that actually intends to use them), for the cost of UPS shipping, if anyone is interested.
     I was experimenting with a pair of Maggie MG12 crossovers and ended up going with some Emerald Physics speakers, some years back.

     ANYWAY: The OP’s systems are stage monitors. Whether vocalists or musicians: hearing themselves, on a stage, with everything else that’s playing around them, is always a challenge and ultra high fidelity, imaging, etc: never much of an issue.

     Not that I mean to put words in the OP’s mouth.   Just sayin’.

     The caps he needs: used from inductor output to ground, in a 12 dB/oct network.  Absolutely no need for such high-Dollar caps as Clarity’s.

     We’d been in contact, via PM, a few times and he’s disappeared, of late.  Perhaps: having found his caps?

@fiesta- We must have been typing at the same time, but: you beat me to the punch, per the thoughts on stage monitors (to much editing, here).

Maybe he solved his cap problem, I hope.

I’m mulling over what I’ve learned, here and elsewhere. I had 17 of these boxes in various stages of disrepair, a handful of them worked sort of OK.

So the first thing I noticed was these blown capacitors, so I posted, but I’ve had a lot of other work to do, assessing blown and not stock drivers, repairing jack plates, and cleaning compression diaphragms and painting duratex etc.

i’m not sure all of them had drivers that met the stock ohm rating, that may have been a factor, although so many of them were blown I have a hard time believing that accounts for everything.

My gut tells me that the bipolar capacitors, while rated at the same voltage, simply couldn’t take the same degree of abuse that the non-polar ones did.
I think I’m going to biAmping a lot of them and rebuild a few of them with really nice crossover parts for when I’m doing smaller gigs and just need a simple set up.

@jamessheyser- If you have blown woofers, Klipsch used 15", 8 Ohm, Eminence, in most of their stage monitors.
     Parts Express carries a wide variety.     Eminence sells direct.    
ie:  https://www.eminence.com/speakers/speaker-detail/?model=Alpha_15A   
and: https://www.parts-express.com/search?order=relevance:desc&keywords=15%22%20eminence     
     The drivers you have, probably were obsoleted, some time ago.  Someone like Bill, at Millersound, if given model numbers from the backs of the woofers and horns, could probably give you any pertinent info.    
       You may discuss having them re-coned, or buying new diaphragms which would save a few bucks  
                     http://www.millersound.net/speaker-reconing-millersound.html   
       If you're in the Central Florida area, try these guys;  
                     https://www.centralfloridaspeakerrepair.com/   
       Don't tell the guys at CFS I sent you.     They'll inflate the prices!  
        I was their competition, for a few years.      Then again: that was forty years ago.

Some are definitely 4 ohm (stock). I have three generations of these so it's hard to know what is or is not stock. Even some of the Klipsch K-43 drivers seem different. And some for sure aren't stock. 

@jamessheyser-    Again: try contacted Millersound, with the driver numbers.    He should be able to fill in the blanks (ie: even whether stock, or not), for you.  
       
          Another avenue, far as possible OEM driver info:    https://www.klipsch.com/support-nav