ROG and silver mica cap voltages?

[Bluesgeetar]

I'm trying to build me a little supply of Silver Mica caps for ROG amp sims builds.  I ain't got a lot of experience with Silver Mica caps so i was wondering if the voltages on them are important.  

I've got most of the values I need except for a few hard to find ones.  I have so far been shooting for 100V Silver Mica caps.  But I am getting down to some harder to find 100V values like 330pf and .0022pf and 47pf.  I have located some 300V jobs and theres plenty of the 500V numbers.  So is voltages on Smica caps just as important as with other caps?

thanks fellers

[petemoore]

As long as the caps voltage rating exceeds the potential it'll see, you'll be fine...for 9v circuits I use 16v or higher rated caps.

[Bluesgeetar]

What is that rule of thumb thing about stay as close to the voltage supply as possible dictating the use of 16V caps electrolytic or tants or 50V-100V in poly films and others.  Something about this will impart more of the sound qualities of the type of cap being used or something. :?

[Fret Wire]

It's about protection. The rule is that the minimum rating of a  cap should be twice the voltage of the power supply. There aren't really any 18v caps around, so the minimum for 9v is 16v, 24v caps for 12v, and so on. What ever cap meets the minimum voltage and physically fits, is fine. The factories skimp on the ratings quite a bit.

So, it's usually 16,25,35, and 50v for electro's. Same for tants. Usually, the poly caps start at 50v, then 63v, 100v. Most of the 250, 400, and 600v poly's are too big to fit in boxes.

Doubt anyone is going to hear a difference in voltage ratings of the same type of cap in a 9v stompbox. Different ballgame for cap ratings in amps, however.