Schematic - PNP (posi ground)
R1
100K /
10K
R2
10K
R4
470R
R5
100K
C1
10n /
15n
C2
4.7u /
10u
C3
100n
C4
47u
C5
10n /
15n
C6
4.7u /
10u
Q1,2,3
PNP Germaniums
ATTACK
1KB
VOL
100KA
T1
100K preset
T2
10K preset
Values in black are for the Tonebender Pro
MkII. Substitute values in blue for Marshall
SuperFuzz or red for Vox Tone Bender MkII.
The schematic above shows the original PNP
- Positive-Ground layout, which is also how
the PCB is designed. What does that mean?
Well, basically it means it won’t play nicely
with ‘normal’ pedals if you try to daisy chain
them on the same power supply. Don’t do it.
It’s perfectly simple to make a NPN -
Negative-Ground version. Use NPN
transistors, flip the orientation/polarity of C2,
C4 and C6, then follow the appropriate wiring
diagram later in these instructions. The -V
connection bV.
Typical hFE ranges for the transistors are:
Q1 - 55-60 Q2 - 70-80 Q3 - 100-140