Replacement capacitors exploding

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...