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Enclosure not stated · 4 knobs

Tagboard Effects

Digitech Bad Monkey - BufferlessVerified

Based on the DigiTech Bad Monkey Overdrive· 6 other boards clone it

Category
Overdrive
Controls
Gain · High · Low · Level
Build
Vero· 19×18· 17 cuts, 11 links
Layout
Verified · Tagboard Effects marks it as built and working
Tags
Overdrive

From the post

Updated 21st January 2013

The Bad Monkey is a very popular low cost pedal which most people have assumed to be a simple Tubescreamer clone but is a little bit more than just a verbatim TS808. It actually bears a lot more resemblance to the DOD Juice Box which is handy because the person who did the trace couldn't get a couple of the cap values and so they have been inferred from the Juice Box schematic.

The layout is simplified from the schematic, and all the FET buffered switching has been removed so it has been put together with true bypass switching in mind, and the input and output buffers have also been removed, so this can be thought of as a Bad Monkey Eternity if you like! :o)

The cap values that were unknown were the 51p and the 220p. The 51p will be fine and is a commonly used value for this kind of filter (increase if you want to soften the distortion more), but you may want to experiment with the 220p and so I'd suggest socketing that one and seeing what you come up with.

If you want a bit more gain from it, try increasing the 100K Gain pot.

Info from Digitech about the original:

The Bad Monkey Tube Overdrive gives your amp a boost just when you need it. It has been compared to the TS-808 but with having the unique ability to smooth out the distortion by use of the low and high EQ controls. Most overdrive pedals give you one tone control knob thus limiting your tonal options. You asked for a pedal that will maintain your guitar's distinct tone and DigiTech delivered! With its rugged design, separate mixer and amp outputs, and amazing tonal options, this pedal truly is a Bad Monkey. From Blues to Rock to everything in between, it will give you that amazing overdriven tube amp sound that will keep begging you to crank it up!

Schematic

This is a board layout, a drawing of where each part goes, and the post may link the schematic it was drawn from. Open the layout at Tagboard Effects. No KiCad fragment has been drawn for this circuit yet.

Parts list 26 rows

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Check before you build · 2 values the reader of this layout was not sure of
  • 5K, two resistors at the lower right by the High wires: printed clearly, unusual value
  • 51p next to D2: printed clearly, unusual value
RefValueNormalizedTypeNotes
Resistors 8
×110R10read from the layout by eye
×31K1kread from the layout by eye
×25K5kread from the layout by eye
×210K10kread from the layout by eye
×222K22kread from the layout by eye
×227K27kread from the layout by eye
×3100K100kread from the layout by eye
×11M1Mread from the layout by eye
Capacitors 10
×151p51pread from the layout by eye
×1220p220pread from the layout by eye
×347n47nread from the layout by eye
×1220n220nread from the layout by eye
×1470n470nread from the layout by eye
×11u1ufilm/box, not electrolytic; read from the layout by eye
×110u10uelectrolytic; read from the layout by eye
×147u47uelectrolytic; read from the layout by eye
×1100u100uelectrolytic; read from the layout by eye
×1330u330uelectrolytic; read from the layout by eye
Diodes 2
D11N41481N4148read from the layout by eye
D21N41481N4148read from the layout by eye
Transistors 1
Q12N50882N5088or similar; read from the layout by eye
ICs 1
×2JRC4558JRC4558ICs are JRC4558 or similar; read from the layout by eye
Potentiometers 4
GainB100KB100kPotentiometerread from the layout by eye
HighB100KB100kPotentiometerread from the layout by eye
LowB100KB100kPotentiometerread from the layout by eye
LevelA100KA100kPotentiometerread from the layout by eye

Other boards based on the DigiTech Bad Monkey Overdrive