Moosapotamus Fat n' Pretty

[Bassmanfox]

I am currently building http://moosapotamus.net/THINGS/Fat-n-Pretty/Fat-n-PrettySCH.gif 

Really quick I know c1 can't be .47pf?  So what is it.  I'd have to say 47pf or .47uF?  Anyone know for sure?  I search the forum and found that same question, but no answer.  Thanks.

[Meanderthal]

 As drawn that would be a low pass filter(Why? Wouldn't that muddy up the compressor?)... but it seems to be missing a decoupling cap also... Good question!

[MetalGod]

47pF sounds about right - just zapping some extreme top end to ground.  0.47uF would be WAAAAY to big (heh).

[ildar]

I'd go with 47pf, fairly common for treble rolloff. A .47pf cap (less than 1pf, btw) is probably non-existent, or at least ineffective.

[moosapotamus]

...or, you can omit it without really changing the sound at all.
R2 and C1 form a low pass RF filter to prevent the circuit from picking up radio stations.
See R.G.'s article...
http://www.geofex.com/circuits/what_are_all_those_parts_for.htm

~ Charlie

[Meanderthal]

 Ahhh... That's what it's doing there! I was just curious, considering that the most common complaint for compressors is that they muddy or color the tone... But if it ain't covering audible frequencies, then I guess it won't be the cause of any grief.

[rankot]

I'd go with 47pf, fairly common for treble rolloff. A .47pf cap (less than 1pf, btw) is probably non-existent, or at least ineffective.

I tried low pass filter calculator (http://www.learningaboutelectronics.com/Articles/Low-pass-filter-calculator.php) and it seems that appropriate value for R=100 ohm and Fc = 33.8kHz (which is quite fine) is 47 nano farads. So the capacitor is most probably 47nF, not pico farads.