Capacitor question...

[Burton]

I'm pretty new to electronics, so I've been browsing parts distributers to get an idea on general pricing for various parts.  (Note: when I am referring to capacitors here, I am referring specifically to Xicon .1uf capacitors, price each - not bulk prices).  I noticed that a ceramic disc capacitor cost ~$.18, while the equivalent film capacitor cost ~$.24, and the electrolytic cost ~$.06.  I was wondering why there is such a broad range for equivalent value capacitors of the same brand.  The only thing I can think of is something extremely specific like maximum operating temperature or voltage, neither of which apply to effects pedals (generally operated at standard temperatures and around 9v), I assume, but please correct me if I'm wrong.  If there is a big difference, which (.1uf) capactiors are generally used for effects pedals and, why?  Do they have an advantage?  All help is appreciated! Thanks!

(In the beginner project, the .1uf FILM-recommended capacitor got me thinking about this - so ultimately, why not go with electrolytic for 1/3 the price?)

[R.G.]

Please read the FAQ and search the forum for more info on capacitors surrounding this question.

The specific answer to your question is (a) the price of anything, including capacitors is a function of the cost of materials, capital equipment to process the material, labor to run the equipment and profit. It's cheaper to make and sell an electrolytic than a ceramic or film. (b) capacitors vary in in their secondary characteristics, such as leakage, dielectric absorption, and equivalent series resistance/inductance. This makes them pass audio signals slightly, but detectably, differently. It's reasonably generally agreed that the insulation material of the capacitor and its construction makes a difference to the sound in some instances. This is why a designer would select one type over another.

It also helps to keep a sense of perspective. Have you read "Effects Economics 101" in the Guitar Effects FAQ at GEO? If not, you really should do that.