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honkytonkwillie
02-22-2016, 03:58 AM
I'm working out details for my first charge coupled crossover. A 14μF cap needs to be replaced by a pair of 28μF caps in series. 28μF isn't a standard value, but I can get close with a 24 and 33μF in series, or a 22 and 39μF.

How big of a deal will this asymmetry be? Would I be better off paralleling a bunch of smaller caps to make a pair of 28μF equivilants? (6.2μF x4 and a 3.3μF would do it)

Hoerninger
02-22-2016, 11:36 AM
It does not matter. :)
For AC the Cs are in series but for DC they are in parallel.
____________
Peter

DavidF
02-22-2016, 04:11 PM
I'm working out details for my first charge coupled crossover. A 14μF cap needs to be replaced by a pair of 28μF caps in series. 28μF isn't a standard value, but I can get close with a 24 and 33μF in series, or a 22 and 39μF.

How big of a deal will this asymmetry be? Would I be better off paralleling a bunch of smaller caps to make a pair of 28μF equivilants? (6.2μF x4 and a 3.3μF would do it)

Multiples will add up to a lot of space and added work. Suggest you go with the larger values and reduce the count of pieces you have to deal with.

One advantage of using multiples is the ability to tweak individual part values to get close to the spec'd aggregate uF value. You can still use small-value bypass caps paralleled to the large caps for that purpose, though, if the larger caps deviate too much. Another advantage is using parts you may already have on hand.