< Drive Bastard > High Gain DIY Overdrive pedal project

[maz]

Quick Overview:

- Type: High Gain Overdrive
- Level of complexity: 1/3
- Nb of parts: 25
- Nb of amplification stages: 2
- IC: LM741 single OP Amp (TL071)
- Input: NPN Transistor 2N3904
- Clipping: Soft (3mm red led)
- Nb of Potentiometers: 3 - (Drive Tone Level)
- Schematic tested: Breadboard
- PCB Layout: Yes
- PNP transfer: Yes
- PCB Size: 21 X 12 holes
- PCB tested: no
- Veroboard Layout: Yes
- Veroboard Size: 16 X 21 holes
- Veroboard tested: no
- Soundtracks: Yes

The Drive Bastard is an High Gain Overdrive project based on the LM741 single OP Amp IC. The inverting input on the IC has been choose as the main amplification stage but also to bring back the inverted signal coming from the common emitter amplifier within the NPN transistor at the input, which also contribute to add some more gain. This is a 3 knobs pedal (Drive - Tone - Level), drive control can be adjusted from mild to a quite agressive overdrive level. The frequency response is inspired from the Marshall JCM800 to emphasize on the mid frequencies of a cranked tube amp while the tone control is very responsive, this is a very dynamic pedal with a modern tone, simple but effective!

You can also experiment with other clipping diodes/leds or fets with the Drain and Gate tied together. The 2N3904 transistor can be replaced with any NPN ... Just make sure to have the correct pinout and pick one with the gain at about 200 hFE. A TL071 IC can also be used but I prefer the LM741, I actually don't have anything else in my part stash but I'm sure you can use many other single OP amp like the NE5534.

Soundtracks:

Clip 1 (2.40Mb) - MP3 : Various music at different setting.
Recording: Stratocaster (bridge dual blade (rail) single humbucker) -> Drive Bastard -> Run Off Groove Condor Cab Sim -> mixer (Flat EQ) -> soundcard -> software (some reverb added).

Clip 2 (858Kb) - MP3 : D Tuned
Recording: Same as above but different mixer EQ.

Clip 3 (1.60Mb) - MP3 : Six (6) takes mixed together starting from drive at 0, 9 o'clock, 12 o'clock, 3 o'clock and finally at max.
Recording: Guitar (same as above) -> Drive Bastard -> Beltone AP-A tube amp (clean at low volume, 8 inches speaker) -> SM57 shure mic -> mixer (Flat EQ) -> soundcard -> software.

Schematic < Tested on breadboard > :





Download the complete pdf project file for direct PnP transfer, layout and schematic.

Download Bill of Materials in txt format.

The Drive Bastard built on Veroboard :



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Have fun!

[bugs]

Sounds awesome! This is a kind of high gain overdrive I am looking for since a very long time

[backslash]

I agree this thing sounds like the pros! really I like it