The Dunlop M236 Super Badass Variac Fuzz is a fuzz pedal built around a Variac control, a knob that changes the voltage level feeding the circuit. Dunlop describes the pedal as providing "snarling, aggressive tones thanks to a hot-rodded vintage circuit." Turning the VARIAC knob counterclockwise simulates the voltage sag of a dying battery, the classic starved-fuzz character; turning it clockwise gives higher headroom and a clearer, more transparent sound1. That makes the voltage sweep the pedal's main voice control, sitting alongside the usual gain, volume and tone set.
The controls
The M236 has four knobs and a footswitch. The VARIAC knob is the distinguishing one: it controls the voltage level reaching the circuit, over a range of 5 to 15 V, which is what gives the pedal its two personalities, sagging and compressed at low voltage, more open and transparent at high voltage1.
| Control | What it does |
|---|---|
| GAIN | Controls amount of fuzz |
| OUTPUT | Controls overall effect volume |
| TONE | Cuts high frequencies |
| VARIAC | Controls voltage level, 5 to 15 V |
| FOOTSWITCH | Toggles effect on/bypass, red LED indicates on |
The TONE knob only cuts high frequencies rather than boosting them, so it works as a roll-off for taming brightness, and the OUTPUT knob sets the overall effect volume independently of how hard the GAIN knob is driving the fuzz1.
Power and connections
The M236 runs on 9 volts DC and draws 17 mA. It takes one 9-volt battery, fitted by removing the bottom plate, or an external supply: Dunlop specifies a 9-volt AC adapter such as the Dunlop ECB003, or the DC Brick and Iso-Brick power supplies1.
The manual specifies 9 volts DC. The VARIAC knob changes the voltage inside the circuit; it is not a power supply setting, and the pedal itself should still be powered at 9 volts DC.
Connections are straightforward: run a cable from your guitar to the M236's INPUT jack, and run another cable from the M236's OUTPUT jack to your amplifier1.
Specifications
All specifications are given at 1 kHz1.
| Specification | Value |
|---|---|
| Input impedance | 300 kΩ |
| Output impedance | 120 kΩ |
| Current draw | 17 mA |
| Power supply | 9 volts DC |
| Variac range | 5 to 15 V |
| Noise floor | -98.5 dBV A-weighted, all controls at mid position |
Where it sits in Dunlop's fuzz range
Dunlop's fuzz catalog leans heavily on vintage designs, from the Fuzz Face family to the Octavio and the Gypsy Fuzz. The M236 stands apart from those by putting the voltage supply itself on a knob: instead of choosing between a germanium or silicon circuit, the player sweeps the VARIAC control between dying-battery sag and higher headroom within one pedal1. For more on the effect type, see Fuzz Pedals.
Videos
Sweetwater
Sweetwater
Guitar Center
Questions
What does the Variac knob do on the Dunlop Super Badass?
The VARIAC knob controls the voltage level supplied to the circuit. Rotating it counterclockwise simulates the voltage sag of a dying battery, a classic fuzz character. Rotating it clockwise gives higher headroom and a clearer, more transparent sound, so the knob works as a wide sweep between saggy, compressed fuzz and a more open response.
Does the Dunlop M236 take a 9-volt battery?
Yes. The M236 is powered by one 9-volt battery, and you remove the bottom plate to install it. It can also run from a 9-volt DC power supply, such as a 9-volt AC adapter like the Dunlop ECB003 or a Dunlop DC Brick or Iso-Brick power supply.
How much current does the Super Badass Variac Fuzz draw?
The M236 draws 17 mA, according to the specifications in the Dunlop manual. All of the pedal's specifications are measured at 1 kHz.
Is the Dunlop M236 true bypass?
The manual describes the FOOTSWITCH as toggling the effect on and bypass, with a red LED indicating when the effect is on. The manual does not use the term true bypass, so the bypass type is not specified beyond that description.
What are the input and output impedances of the M236?
The M236 has an input impedance of 300 kΩ and an output impedance of 120 kΩ, per the specifications in the Dunlop manual. All specifications are given at 1 kHz.
What power supply works with the Dunlop M236?
Dunlop specifies a 9-volt DC supply: a 9-volt AC adapter such as the Dunlop ECB003, or a Dunlop DC Brick or Iso-Brick power supply. The pedal also runs on one 9-volt battery, installed by removing the bottom plate.
Sources (1)
- M236.pdf, Dunlop Manufacturing, Inc., 2019
