On the left is one pole of a 6 position 2 pole switch. The other pole is used in the other channel. The switch is the input selector in a preamp or integrated amplifier. The swinger of the switch goes to one end of a 1 u f capacitor. The other end of this cap goes to the input of the response control circuit R C C. The input of the R C C goes through a 24 k ohm resistor then a 220 p f capacitor to the C W end of the treble control, 250 k ohm pot. The C C W end of the treble control goes to another 220 p f cap. The other end goes through a 24 k ohm res to the R C C output. The wiper of the treble pot goes through a 220 k ohm resistor to the center of the R C C. The R C C input also goes through a 56 k ohm resistor to the C W end of the bass control, 250 k ohms. The C C W end goes through another 56 k ohm res to the R C C output. There is a 0.0022 u f cap connected from one end of the bass pot to the other. The wiper of the bass pot goes through a 1 meg ohm resistor to the center of the R C C.

The center of the R C C goes to the grid, pin 7 of a 12AX7. The grid also goes through a 2.2 meg ohm to ground. The cathode, pin 8, goes through the parallel combination of a 1.8 k ohm resistor and a 100 u f cap to ground. The plate, pin 6, goes through a 100 k ohm resistor to plus 250 volts. The plate also goes through a 0.47 u f cap to the output side of the R C C. This same point goes to the output of the tome control circuit. The output also goes through a 3.3 meg ohm resistor to ground. End verbal description.
Go back.