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Making a bipolar cap? (electrolytic? using 2 caps?)

Hi all,

I need a high value Bi-Polar electrolytic (200uF, 132.5uF, etc...), I remember that if you take two polarized electrolytics and join the positives (? or was it negatives?) I can basically end up with a non polarized cap (bi-polar).

I just need to filter off some low frequencies from the front speakers in my car, 4ohm impedance, and I want to cross them over at 200hz at 6db/octave, I'll basically need a

200uF cap, 300hz would be 132.5uF.

Anyhow, fill me in? I can't remember, and now I am so dependant on computers and google, I forgot how to open a book and read. Sad, very sad.

thanks ;)

--
Myron Samila
Toronto, ON Canada
Samila Racing
http://204.101.251.229/myronx19
Reply to
Myron Samila
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remember that if you

negatives?) I can

my car, 4ohm

basically need a

computers and google, I

Reply to
Art

Two caps in series = half the capacitance of one.

remember that if you

negatives?) I can

my car, 4ohm

basically need a

computers and google, I

Reply to
CWatters

True, it is hard to find high value non polarized electrolytics. Finding two polarized

400uF caps would be much easier and probably a lot cheaper.

Working voltage is quite low, since a 45w car audio deck doesn't put out very much, works out to 20v at most?

A 1200 watt amp puts out somewhere around (pro amp of course, concert audio)

56-70 volts

-- Myron Samila Toronto, ON Canada Samila Racing http://204.101.251.229/myronx19

Reply to
Myron Samila

On Sat, 20 Dec 2003 12:12:37 -0500, "Myron Samila" Gave us:

polarized

much, works

56-70 volts

To increase capacitance place two in parallel, and two more in parallel, connect those pairs in series opposed fashion.

That restores the original capacitance value of the single can.

Remember to use peak voltages for this application, when determining what cap ratings to use, and don't buy electrolytics from surplus houses ever.

They dry out with age... badly. That changes there cap value... badly.

Reply to
DarkMatter

that if you

negatives?) I can

Plus or minus together doesn't matter, as long as it is plus-to-plus or minus-to-minus.

car, 4ohm

basically need a

A problem may be the tolerances. Bipolar caps should have narrower tolerances as they are meant for filtering. Ordinary electrolytics are used for power supplies; I remember -10% +50 % as tolerance bands.

Thomas

Reply to
Zak

Tolerances wouldn't be a problem, it could be as far off as 30%, and you wouldn't hear any difference in the sound.

At a crossover slope of 6db/octave, the only difference between one speaker and another would be at the crossover point, and then, you'd never be able to tell the difference of a few percent since this particular slope quickly disappears in the next lower octave.

-- Myron Samila Toronto, ON Canada Samila Racing http://204.101.251.229/myronx19

remember that if you

negatives?) I can

car, 4ohm

basically need a

Reply to
Myron Samila

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