2n capacitor - substitutions?

[lincolnic]

I'm having a lot of trouble finding a 2n cap for my Krankosaurus build, can't seem to find one on PPP, SB, or Mouser. Can I substitute 2.2n instead? How will that affect the sound? Thanks for the help.

[eniacmike]

2n has a cutoff frequency of 7957hz
2.2n has a cuttoff frequency of 7234 hz.

the two low pass filters in a series is a 2nd order low pass filter. a 1st order low pass attenuates at 20 db per decade, a 2nd order at 40 db per decade

these 2nd order low pass filters roll of highs very quickly above the cutoff frequency.

in a sense 2.2nF isn't going to hurt. you can also just wire up two 1n caps in a series to make a 2n cap.

there is probably some phase shift things going on too with the 2nd order low pass filter but I don't really understand how all that works enough to explain it.

http://sim.okawa-denshi.jp/en/CRlowkeisan.htm - really cool rc filter calculator that graphs your input too.

[lincolnic]

Thanks Mike. I think I'll wire up two 1n caps to stay true to the original design - shouldn't they be in parallel, though? I thought the rule was resistors add in series, caps add in parallel?

[eniacmike]

you are correct. very sorry about that.

[rps-10]

Sorry for raising an old thread and a nooB questiona t the same time, but is 2n the same as 2000pF ?

[marmaliser]

Yes 2000pf = 2nf - Here is a handy little chart http://www.justradios.com/uFnFpF.html

[rps-10]

Phew thanks, for putting my mind at rest, was overly worried about the lack of a "f" after the n 

Took a wild guess and ordered a 2000pf after checking this: http://www.electronics2000.co.uk/data/itemsaf/capconv.php  but I think I also found your link as well on my travels.

[DutchMF]

Hi,

Do you know the maths for calculating series and parallel resistors? With capacitors it's exactly the other way around, I think there is an article on Wikipedia that explains this stuff, will look it up!

Paul

[DutchMF]

Here's the link: http://en.wikipedia.org/wiki/Capacitor

Another useful one: http://www.hobby-hour.com/electronics/resistorcalculator.php