Gretsch 7798 schematic

To pin 11, V+, on both opamps

IN

9V

100K

4

+

0.1

uF

100K

220pF

5

100

25pF 25pF

12

6

220K

3

10

10K 0.1uF

1N4001

1N4001

220K

10K 100K

Distort

0.47uF

4

5

12

3

10

6

0.47uF

330K

+

10uF

OUT

Gretsch Controfuzz Model No. 7798

The Gretsch Controfuzz is a variant of the op-amp-driving-diode-clipper type of distorter. The only unusual features are that the distortion is run at high
boost all the time in the first opamp, and then subtracted from the dry signal in the second opamp. The amount of distortion mixed in is determined by the
"Distort" control, and the overall volume level when the distortion is switched in is set by the "Boost" control.

10K
Boost

The op amps are both type 748, which needs a compensation capacitor (25 pF in this case) to be stable. Other modern opamps should work.