The KMA Machines CHIEF DISRUPTOR is a fuzz/distortion pedal from German pedal maker KMA Machines, built around a Big Muff-style circuit with what the maker calls a stacked topology1. What sets it apart from a standard muff clone is its tone shaping: a parametric mid EQ you can switch in and out with a footswitch and sweep with an expression pedal, an active bass and treble EQ, a switchable top boost, and a pre or post clean blend for a tight low end12.
KMA positions it as "the ultimate 'muff-style' drive, with stacked topology," descended from the classic muff sound players already know1. Delicious Audio called it KMA's "take on the uber-flexible, do-it-all Muff-style fuzz"3. It was announced in late January 2022 and remains current and available24.
The controls and modes
The Disruption control is the gain knob, and KMA says it spans from low gain drive up to doom tones1. Around it sit the tone shaping controls that make this more than a straight muff copy:
| Control | What it does |
|---|---|
| Disruption (Gain) | Gain from low-gain drive to doom tones1 |
| Mids Frequency | Sets the center frequency of the parametric mid EQ5 |
| Bass, Treble | Active two-band EQ2 |
| MIDS footswitch | Activates the parametric mid EQ, with a yellow on/off LED3 |
| Top-Boost | Switchable boost for more crunch when required2 |
| Clean blend | Pre or post clean blend for a tight low end1 |
| Expression input | External control of the mid EQ, allowing filter or pseudo-phase tones1 |
There are also internal trimmers for Mid Q and Top Boost level, so the shape of the mid band and the amount of top boost can be dialed in under the hood5.
The three gain modes are the heart of the pedal's character. KMA describes them as three distinctive gain structures1:
On Heavy, KMA's own description is unapologetically muff: "Heavy Mode is the essence of what we all love about muffs. Heavy, sustaining and crazy thick fuzzy distortion, with bone-shaking lows and chewy mids"1.
The parametric mid EQ is the feature most reviewers highlighted. MusicRadar described it at launch as "foot-switchable and expression-controllable," alongside "a switchable Top-Boost for more crunch when required"2. Because classic muffs scoop their mids, a boostable, sweepable mid band is what lets the Chief Disruptor cut through a mix or push an amp harder.
Power and connections
The Chief Disruptor runs on a regular 9V DC power supply, center negative, with a 2.1mm barrel connector1. Its maximum current draw is over 160mA, and the maker notes power is not supplied with the pedal15.
At over 160mA, this pedal draws more current than a typical analog fuzz and has no battery option. It needs its own 9V DC output from a powered pedalboard supply; a small daisy chain shared with low-current analog pedals may not keep up.
Input and output jacks are top-mounted, which keeps the pedal's footprint usable on a crowded board6. The expression input sits alongside them for external control of the mid EQ1.
History and the Bloodstone Edition
What reviewers said
Guitar Pedal X's Stefan Karlsson, who first reviewed the pedal in January 2022, revisited it in his 2026 roundup of mid-size Big Muff-style fuzzes5:
"This is a cracking all-rounder Big Muff"
Stefan Karlsson, Guitar Pedal X4
Of the Bloodstone Edition he wrote that it is "All-round a fantastic extended range Big Muff - which works equally great on Bass!"5. Delicious Audio's Paolo De Gregorio, writing at launch, judged from the maker's demo that "the KMA Machines Chief Disruptor sounds like an inspiring and flexible device"3.
For players comparing muff-style options, the Chief Disruptor's differentiators include its foot-switchable and expression-controllable parametric Mid-EQ, its Pre or Post Clean Blend for a tight low end, and its three distinctive gain structures: Vintage (dynamic), Tight (more focussed) and Heavy (sustaining and thick). KMA's own alternatives, like the Mandrake Octo-Shrieker octave fuzz, cover different territory entirely21.
Videos
KMA Machines
The Pedal Zone
Patrick Hunter
Questions
Is the KMA Chief Disruptor true bypass?
Yes. KMA Machines lists the Chief Disruptor as true bypass, so with the pedal off your signal passes through without active buffering. The Bloodstone Edition shares the same true bypass switching.
What do the Vintage, Tight and Heavy modes do on the Chief Disruptor?
They are three selectable gain structures. Vintage is the dynamic one, Tight is more focused, and Heavy is sustaining and thick, which KMA describes as the essence of a muff with bone-shaking lows and chewy mids. MusicRadar described the same trio as Vintage (dynamic), Tight (focussed) and Heavy (thick and sustaining).
Can you control the Chief Disruptor mid EQ with an expression pedal?
Yes. The pedal has an external expression input for the parametric mid EQ, which KMA says also allows for filter or pseudo-phase tones. MusicRadar called the mid EQ foot-switchable and expression-controllable at launch.
Does the Chief Disruptor have a clean blend?
Yes. It offers a pre or post clean blend, which KMA positions as a way to keep a tight low end. Guitar Pedal X found the pedal works equally great on bass, which is where a clean blend matters most.
Are the Chief Disruptor jacks top-mounted?
Yes. Guitar.com reported at launch that the Chief Disruptor has top-mounted jacks for the input and output, which saves width on a pedalboard.
Sources (6)
- CHIEF DISRUPTOR, KMA Machines
- The Chief Disruptor has arrived: it's KMA Machines' new Fuzz/Distortion pedal, MusicRadar, 2022-01-28
- KMA Machines Chief Disruptor Fuzz, Delicious Audio, 2022-01-27
- Guitar Pedal X, Guitar Pedal X, 2026-08-28
- Guitar Pedal X, Guitar Pedal X, 2026-07-16
- KMA Machines’ Chief Disruptor fuzz adds a host of tone-shaping to a Big Muff circuit, Guitar.com, 2022-01-31
