On many of the schematics for effect pedals I find on line, there is no mention of what voltage rating needed for electrolytic caps. how do I determine this? TIA
I just aim higher than the voltage the circuit uses. If it's 9V, I use 16V or higher.
Ok then, so 25vdc should be cool
Only thing to be careful of is higher voltage means bigger cap, and you may run into cases of things being a bit too thick to fit. Usually not a big issue if you keep things under 50V (maybe under 35V for higher values) but some layouts can be finicky.