Beginner Capacitor Question

[Clegg]

Hi. I'm a relative beginner about to start my second fuzzbox. I've read the FAQs on capacitors on this site (which were really helpful!) but i still have a couple of questions...

1) If i can't find a specific cap and the schematic specifies say, a ceramic cap, would it really matter if i subbed it for a tantalum or electrolytic cap for the same value? Would the FX sound any different or just not work?

2) I  read in the FAQs that the value and the voltage were important but if the schematic specifies min. 16v caps would ones with 63v or 100v ratings work? Or have i missed the point?

3) What are Film caps? Some schems I've seen ask for them but I can't seem to find any suppliers that supply them or any info on them. Is there another name for them or are they called something different in Europe (I'm in the UK, looking at UK suppliers)?

I know this is probably a bit annoying cause they're all pretty basic questions, but any help would be greatly appreciated.

Thanks!

[oldschoolanalog]

UTSF!

[R.G.]

1) If i can't find a specific cap and the schematic specifies say, a ceramic cap, would it really matter if i subbed it for a tantalum or electrolytic cap for the same value? Would the FX sound any different or just not work?

As a general case, any cap with the right capacitance and voltage rating will work. Changes to the tone you get are very tiny, small differences indeed. However, the substituted cap must not have its own needs violated, as in the case for electrolytic (aluminum and tantalum) capacitors. These kinds of caps must have DC polarization across them at all times. So you cannot use an electrolytic cap (aluminum or tantalum) in a position where the signal across it would ever cause the voltage to be reversed. These types need the DC polarization. Otherwise, the type of cap is unimportant to a first approximation.

2) I  read in the FAQs that the value and the voltage were important but if the schematic specifies min. 16v caps would ones with 63v or 100v ratings work? Or have i missed the point?

It's just what the FAQ says - the minimum voltage is whatever. The maximum can be whatever you have. This gets out of hand quickly as the physical size of the cap goes up quickly with voltage and you may not be able to get a 250V cap inside your box, even though it would work perfectly if you could connect it up.

3) What are Film caps? Some schems I've seen ask for them but I can't seem to find any suppliers that supply them or any info on them. Is there another name for them or are they called something different in Europe (I'm in the UK, looking at UK suppliers)?

"Film" is a generic term for plastic film insulation. You will see these called names like mylar, polyester, teflon, polystyrene, polypropylene, polycarbonate. Mylar is a brand name of polyester, and is the most common film type.

[Clegg]

Great! Thanks a lot thats really covered everything that i wasn't too clear on... Sorry again for being simple. xxx

[Peter Snowberg]

Welcome to the forum and best of luck on your build!