[Lost81]

Hi, I notice two 220uF 50V bi-polar electrolytic capacitors in a speaker crossover. The speakers were manufactured in 1997.

Now, the capacitance value of electrolytic capacitors deterioriate over time, yes?

I am aware of all the arguments against mucking with the capacitors in the crossovers as they are matched to the impedence of the drivers, but this argument is moot if the capacitance value of the electrolytic capacitors decrease over time.

FWIW, I am considering replacing the two 220uF bi-polar capacitors with the expensive Black Gate WK 220uF 200V bi-polar capacitors (30mm x 25mm) or the Black Gate NH 220uF 160V bi-polar capacitors (30mm x 25mm).

I do have a capacitance meter (accuracy +/- 0.5% @ 23 C) but if the value of the stock capacitors have deteriorated over time, then it would be impossible to match the replacement capacitors to the original values--which is unknown.

Thanks!


-Lost81

[Dan Banquer]

From what many of us have observed in power supplies is that capacitance stays pretty much the same but the ESR (equivalent series resistance) increases. Whether this holds true for loudspeaker caps I don't know. Considering the relatively young age (1997?) and that usually electrolytic capacitors in power supplies are generally good for 15 years, this does not appear to be an issue.
Hope this helps:
            d.b.

[Lost81]

Thanks, Dan  


-Lost81