Home » Audio » Group Build » Multiple caps vs. single cap?
Multiple caps vs. single cap? [message #31152] Wed, 08 June 2005 07:46 Go to next message
colinhester is currently offline  colinhester
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Is there an advantage to using multiple caps to obtain a capacitance value versus a single cap of equal value?

Re: Multiple caps vs. single cap? [message #31153 is a reply to message #31152] Wed, 08 June 2005 13:31 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
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There are two issues that come into play right off the top of my head. One is an advantage, the other, a disadvantage.

The advantage of using smaller caps is you can generally get better parts. This isn't necesarily true of very small components, but since you're talking about using multiples, I'm assuming you're working with cap values larger than 1uF, probably larger than 10uF. Larger values are usually metalized film and you can replace them with a group of caps that use a metal foil.

The disadvantage is that each one has it's own self resonance and other features distinct to the capacitor. So by using a group, you may introduce a very small amount of signal splitting. One cap may act differently than the others, causing a different signal modification through each of the signal paths. It's pretty small though. And this has it's own advantage, in that if you use two identical components and you can identify their orientation, you can actually connect them in opposite directions to act as a conjugate. Whatever differences there are, if asymmetrical according to polarity, this will cancel out. And internal resistance and inductance is paralleled and therefore reduced too.

All these are pretty tiny effects. Don't be too concerned about connecting caps in parallel to increase value. Just something to think about as you decide what parts to buy and how to connect 'em up.


Re: Multiple caps vs. single cap? [message #31154 is a reply to message #31153] Wed, 08 June 2005 20:54 Go to previous messageGo to next message
colinhester is currently offline  colinhester
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Cannot discuss too much in detail, but I need a good source of high voltage oil (motor run) capacitors. I'm looking for 10uF at 660V. Any good suppliers that you know of?......Colin

Re: Multiple caps vs. single cap? [message #31155 is a reply to message #31154] Wed, 08 June 2005 22:17 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
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Mouser and NTE have 'em and I think Digi-Key does too. I'd stick with new production because these caps don't last forever.


Re: Multiple caps vs. single cap? [message #31156 is a reply to message #31155] Fri, 10 June 2005 10:47 Go to previous messageGo to next message
colinhester is currently offline  colinhester
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Unless I'm just missing the boat, these guys do not carry these. With any luck I'm going to Mendelsons tomorrow to see twhat treasures I can find......Colin

Re: Multiple caps vs. single cap? [message #31160 is a reply to message #31156] Fri, 10 June 2005 14:16 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
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Registered: January 2001
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They have 'em. Seach the websites or give them a call. Here's a sample listing of caps at Mouser:

And here's a datasheet for one of 'em:



Re: Multiple caps vs. single cap? [message #31167 is a reply to message #31152] Fri, 10 June 2005 22:58 Go to previous messageGo to next message
Forty2wo is currently offline  Forty2wo
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Hi Colin,
Any of the name brand motor run caps will ok at that voltage.
The ASC caps from Percy, Angela or ebay are rated 440VAC.and are good for much higher DC. I am planing to use them in my 600-700 volt DRD.
Someone had asked ASC for DC Rateing I think on A.A, and thay were not shy with there high DC rateings...John

Re: Multiple caps vs. single cap? [message #31170 is a reply to message #31167] Fri, 10 June 2005 23:29 Go to previous message
colinhester is currently offline  colinhester
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Registered: May 2009
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Thanks for the info. This going to save me a lot of money The circuit I'm considering calls for an oil cap rated at 10uF @ 1000V. It's the first cap after the rectifier in a CLCLC filter. What is the lowest VAC rating I could safely get away with, in your opinion.....Colin

PS. How is the DRD coming? PLEASE keep us posted......

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