Author Topic: HELP!!! Need some knowledge spilled on capacitors!  (Read 5918 times)

Guitar Guy

HELP!!! Need some knowledge spilled on capacitors!
« on: October 07, 2012, 02:03:19 PM »
OK, going to attempt a sweet honey clone. I ordered most of the parts already, all i need is the jacks, knobs, and someother small stuff. but i need some caps. I'm lookig as several schems/layouts and until I saw these I thought caps were either mono or electrolytic. they both specify either a box cap or poly cap. After looking at a lot of sites, I went to Mouser and they have polystyrene, polyester, polyphenol, etc. could some one clear this up for me and pointme to which one I need for this pedal? thanks in advance!

Govmnt_Lacky

Re: HELP!!! Need some knowledge spilled on capacitors!
« Reply #1 on: October 07, 2012, 02:20:07 PM »
Opinions vary however...

IMHO, there are polarized caps (electrolytic, tantalum) and there are non-polarized caps. The type of non-polar caps are usually driven by the cost. Personally, I use whatever is available whether it be ceramic, poly, box, etc.

Bottom line.... Use what ya got  ;D
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Jdansti

Re: HELP!!! Need some knowledge spilled on capacitors!
« Reply #2 on: October 07, 2012, 03:08:15 PM »
I generally agree with GL^, but as he said, opinions vary.

For cap values above 1uf, you'll almost always use an aluminum electrolyic. Sometimes the schematic may call for a tantalum electrolytic or a non-polar cap.

For non-polar values under 1uf, you have a selection of ceramic and "poly" (polystyrene, polypropylene, etc.) (there are electrolytics <1uf, so follow the schematic).  I try to use poly caps for caps that are in the signal chain. Ceramics can sound harsh and they can be microphonic.  When the values get low, ceramics are often the only choice.

 For most pedals, there will not be a noticeable sound between polystyrene and polypropylene, so go for what's available.

Two other factors that affect cap selection are voltage ratings and physical size.  I try to choose caps that have a voltage rating of 1.5 to 2 x the voltage they will see.  It won't hurt to have a higher rating than necessary.   Of course, the cap has to fit on the PCB.
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Perrow

Re: HELP!!! Need some knowledge spilled on capacitors!
« Reply #3 on: October 07, 2012, 03:33:23 PM »


All 470nF, green one $0.07, grey ones $0.20. Pick the one that fits your wallet, adapt your board to fit your cap.
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