Determining capacitor type from schematic?

[drmathprog]

When I look at a schematic and see various unpolarized capacitor circuit symbols, how do I decide what type (i.e., polyester film, electrolytic, maybe others I haven't learned about yet) I should use in a build?

[jg]

When I look at a schematic and see various unpolarized capacitor circuit symbols, how do I decide what type (i.e., polyester film, electrolytic, maybe others I haven't learned about yet) I should use in a build?

You try as many as you can in all the locations of your circuit. You compile a list of the capacitor types you like it the various positions in the circuit. After you have built many, many pedals, you will notice a trend that you like such-and-such cap in such-and-such circuit more than the others for certain reasons.

If you are trying to emulate what the big companies chose, pick the cheapest one. That will get you there 90% of the time.

[drmathprog]

So there is no functional difference between different types of unpolarized or between polarized? How about between unpolarized and polarized? Can I substitute a polarized for an unpolarized and vice-versa, or are they strictly not interchangeable?

[jg]

So there is no functional difference between different types of unpolarized or between polarized? How about between unpolarized and polarized? Can I substitute a polarized for an unpolarized and vice-versa, or are they strictly not interchangeable?

You can substitute polarized for unpolarized if there is a potential difference. If there isn't (which is usually why you use the unpolarized one) then you need to use a unpolarized cap or use 2 polarized capacitors of twice the value, connected in series with the + connected together (that is what is inside a Bi-polar electrolytic capacitor). You will often see this configuration in the feedback loop of an integrator in a LFO generator.

[drmathprog]

Thanks.