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Z.Vex Fat Fuzz Factory Pedal Review

The FFF includes a switch that greatly expands the low end and shifts the range of its famous oscillating feedback to much lower registers.

When the Z.Vex Fuzz Factory hit the scene in the winter of 1995, there was nothing out there quite like it. Its strange, unruly sounds and twitchy sensitivity were in stark contrast to the typical fuzz units that most players were used to. Younger guitarists might not realize that the choices for fuzz pedals were pretty limited at the time, and for adventurous guitarists looking for fresh sounds, the Fuzz Factory and its mad timbres seemed like a prayer answered.

It has been 18 years since the Fuzz Factory appeared, yet the pedal continues to be wildly popular amongst experimentalists, noise-makers, and guitarists looking to add more—and more daring—flavors of fuzz to their music. But with the exception of the Theremin-like Fuzz Probe, the Fuzz Factory hasn’t really been updated with any new abilities for generating additional tones. And this explains why the new Fat Fuzz Factory is creating so much excitement.

The Fat Fuzz Factory builds upon the same core components and tone-generating capabilities of the standard Fuzz Factory—using new-old-stock (NOS) ’60s germanium transistors and a highly sensitive set of controls—but also includes a switch that greatly expands the low end and shifts the range of its famous oscillating feedback to much lower registers. This switch not only makes the Fat Fuzz Factory a beastly fuzz generator for guitar, but also helps it enhance the lower-register output of basses with Earth-shattering results.

Boss Hogg
Just like the original Fuzz Factory, the heart of its new portly brother is a pair of high-gain, NOS germanium transistors, which are attached to a hand-assembled and populated circuit board. It also uses true bypass switching and runs on either a 9V battery or a Boss-style power adapter, but because it only pulls 4 mA—which is astonishingly small—it will be a long time before you have to replace the battery. The pedal comes in two flavors—a handpainted version that’s completely assembled in the U.S. and a more affordable Vexter edition that’s partially built in Taiwan and sports a silk-screened motif.

The pedal uses five highly interactive controls for volume, gating, compression, drive, and a menacingly labeled stab knob, which can either change the pitch of the pedal’s oscillating squeal or the tone of the fuzz, depending on where the other controls are set. Because moving one control can have a drastic effect on how the others react, dialing them in can, at first, seem challenging. Thoughtfully though, the manual provides a few sample settings to get you started with high-gain compressed fuzz, Velcro-ripping tones, and cleaner Octavia-type effects. Above the drive and stab knobs lies a three-way switch for setting the low-end frequency range. When set to 1, the pedal is in standard Fuzz Factory mode. Moving it to positions 2 and 3 add more sub-harmonic intensity, and gradually darken and thicken the fuzz to degrees well beyond what the standard Fuzz Factory is capable of.

In this environment, sustained single notes from the Les Paul’s bridge pickup had nearly as much body as full chords, and heavily gated low notes played with the neck pickup shook the room with a fat, synth-like snarl.

Tubby Tone
Even though the Fat Fuzz Factory was designed to add more low-end muscle to the classic Fuzz Factory sound, the fact that you can operate it as a standard Fuzz Factory is one of its best features. Putting the mode switch in position 1 yields the pedal’s brightest and sharpest tones, and its clear and uncluttered tonality make it the best setting for newcomers, as well as the best way to hear how the controls interact and affect the tone.

I found that with a Les Paul and a Mesa/Boogie Dual Rectifier, Z.Vex’s pre-prescribed compressed fuzz setting—gate at 3 o’clock, comp at 9 o’clock, drive and stab maxed, and volume to taste—yields a bright and gated fuzz tone that’s a great place to begin crafting your own sounds.

Pushing up the comp control softens the highs and the attack, which also causes the gate control to squelch the sound harder, resulting in a cool, 8-bit video game-sounding fuzz. Dropping the comp and drive to their lowest settings and turning up the gate to around 2 o’clock applies a low-gain, upper-octave effect to each note. These are only a couple of examples that can be discovered fairly quickly. Deeper tweaking, however, can reveal all sorts of otherworldly tones—smooth fuzzes that drop notes down an octave after holding them for a few moments, motorcycle engine revving, space-age ray gun bursts, and much, much more.


Pros: Enormously versatile. Can be run in standard Fuzz Factory mode. Minimal battery draw. Massive volume capability. Can produce warm Moog-like emulations with both guitar and bass.

Cons: Relatively steep learning curve. Finicky with pedal-chain placement. Switching to modes with more low end can introduce sudden oscillation.


Ease of Use:



Street: $329 (handpainted) or $199 (Vexter)

Moving the switch to position 2 adds considerable lows to the tone and makes the pedal darker sounding. There are still plenty of the Fuzz Factory’s characteristic sizzling highs in the mix, but you’ll hear a meaner, less razor-like edge than before. In this environment, sustained single notes from the Les Paul’s bridge pickup had nearly as much body as full chords, and heavily gated low notes played with the neck pickup shook the room with a fat, synth-like snarl. Lowering the gate control dropped the pitch range of the fuzz oscillation too, making it easy to dial up droning, gut-shaking whines that alternate pitch like a demonic Theremin.

With some settings though, it was pretty obvious that changing modes also had an effect on the range of various controls. Switching to position 2 caused some of my favorite non-oscillating tones from position 1 to instantly oscillate—requiring me to tweak the pedal’s gate and comp controls to get rid of the whine.

The pedal’s most corpulent tones come from the bottom-heavy position 3. This mode works particularly well when matched with a high-gain setting and single-note runs on higher strings, which receive a pronounced bump in presence. Adding more gating to higher-gain settings yields a grinding synth-like tone that dies with a gnarly sputter—almost as if someone directly hard-wired a dual octave-down pedal to a circuit-bent Casio keyboard. Because of the very dense and complex tones you get in this mode, it’s easy for chords to turn into a jumbled mess. It’s best for single notes that need a little extra kick, or bassists who need more depth and intensity in their lines.

The Verdict
The Fat Fuzz Factory offers a huge range of fuzz tones. The mode switch’s position 1 has all the endless fuzz variations of the standard Fuzz Factory. But the switch’s additional positions open the gates to two very different-sounding harmonic ranges that deliver everything from tubby stoner fuzz to total low-end Armageddon. It’s a touchy pedal that requires some patience and willingness to experiment, but with persistence it’ll reward you with a level of flexibility and tone that exceeds its formidable and very influential predecessor.