Purpose of the "fizzy" (PI) cap?..

RussB

low rent hobbyist
Messages
11,156
It's there to supress high frequency oscillations

The higher the value, the more high frequecies will be diminished. In Marshall circuits, I have gone as high as 180pf and couldn't hear a difference from the stock 47pf cap. I could hear a 250pf cap
 

donnyjaguar

Member
Messages
4,194
The capacitor reduces the gain of the amplifier at frequencies above its normal operation due to phase reversal through the output transformer. To my knowledge its not a "tone shaping" component and RussB's experiments bear this out.
 




Trending Topics

Top Bottom