ampage Tube Amps / Music Electronics	For current discussions, please visit Music Electronics Forum.

ampage archive

Vintage threads from the first ten years

Bypass caps in mixer circuits

7/9/2000 1:33 AM
SteveG	Bypass caps in mixer circuits I've just been looking at a schematic for a four input-type Marshall. My question concerns the part of the circuit where the two channels meet and are mixed through two 470k resistors. One of the channels has a bypass capacitor to boost the relative treble content of the signal, but since there should be almost no grid current (and therefore no significant voltage drop across the resistor), this shouldn't work! Obviously, there's something wrong with my analysis, but what, exactly? Cheers Steve

7/9/2000 1:33 AM

SteveG

Bypass caps in mixer circuits

I've just been looking at a schematic for a four input-type Marshall. My question concerns the part of the circuit where the two channels meet and are mixed through two 470k resistors. One of the channels has a bypass capacitor to boost the relative treble content of the signal, but since there should be almost no grid current (and therefore no significant voltage drop across the resistor), this shouldn't work! Obviously, there's something wrong with my analysis, but what, exactly?

Cheers

Steve

Replies:

Ray Ivers Steve,The action of... -- 7/9/2000 2:09 AM