Univox Super-Fuzz

The Univox Super-Fuzz is a 1968 octave fuzz: a fuzz pedal that adds a high octave alongside the distorted note, turning any note or chord into a thick, searing texture¹. JHS describes the effect as one that "turns any note or chord into a thick and searing texture"². It is the fuzz behind Pete Townshend's Live at Leeds tone, and it was used on countless recordings in the late 60s and 70s¹³.

The circuit was created by Shin-Ei, a Japanese effects maker, and sold under dozens of brand names around the world, of which Univox, the American brand, is the one players remember most³⁴. The original is long out of production, but it saw a resurgence in the 90s during the grunge and alternative rock era, and today it survives in a long line of clones, re-creations and DIY projects³.

Where the Super-Fuzz came from

The Super Fuzz came from Shin-Ei, and the original Univox Super Fuzz dates to 1968¹. Its first incarnation was not a compact pedal at all but a large unit called the Psychedelic Machine⁶. Shin-Ei's circuit also appeared under a long list of OEM brands, including Ace Tone, Apollo, Companion, Crown, Jax, Kent, Memphis, Teisco and Univox, plus Rose Morris's Shaftesbury imprint⁷.

Because of legal issues, the Super Fuzz circuit was rebranded and sold under different names by various companies⁴. Tru-Fi's history of the pedal names the notable variations: the Univox Super Fuzz, the Ibanez Standard Fuzz, and the FY-6 Super Fuzz by Yamaha⁴. Shin-Ei itself still lists the FY-6 Super Fuzz on its own site today, under both the Shin-Ei and Astron brand names⁵⁸.

The pedal's look is as remembered as its sound: Godlyke calls it "that legendary blue and orange monster"⁹. Its best known user association is the Who. Godlyke's account states the pedal "was used on countless recordings in the late 60's & 70's, most notably the Who classic 'Live at Leeds'"³, and General Guitar Gadgets calls the circuit "the 1968 octave fuzz behind Pete Townshend's Live at Leeds tone"¹.

How it works: an octave fuzz with a phase splitter

What separates the Super-Fuzz from a plain fuzz pedal is how it generates its octave. The circuit uses six transistors and two germanium diodes¹. Two of those transistors, Q4 and Q5, form a phase splitter that doubles the signal for the octave-up effect¹. Godlyke describes the same stage from the signal's point of view: the Super Fuzz "used dual germanium diodes and a unique full-wave rectification circuit to produce sizzling upper octave" harmonics³.

In practical terms, the rectification turns the waveform's negative halves into positive ones, which stacks even harmonics an octave above what you play. Single notes and higher fretwork give the strongest octave effect; the result is a fuzz that sits in the same octave-up family as the Octavia, though the two circuits get there by different means³¹¹⁰.

Not every Super-Fuzz was built identically. Some versions did not have the R22 trimmer used to balance the Q4 and Q5 transistors¹, a detail that matters to anyone rebuilding the circuit, since the balance of that phase splitter is what keeps the octave effect strong.

Controls: Balance, Expander and the tone switch

The control layout is minimal. Shin-Ei's own FY-6 pages describe it: "The unit is controlled by the Balance/Expander knobs and the slider switch (Tone 1 & 2) which are located on the left side" of the unit⁵, and the Astron FY-6 page repeats the same arrangement⁸.

The tone switch is the pedal's personality control. On the General Guitar Gadgets replica, up is the stock notched sound with the mids cut, and down is flat and fuller¹. The kit's documentation describes the two positions as a switch "between the popular nasally, raspy fuzz sound of the sixties to a more full bodied fuzz"¹. The scooped, notched position is the sound most players associate with the pedal.

The replica project also leaves room for modifications, including replacing the tone switch with a tone potentiometer, using a 10k linear taper pot in the R26 position¹.

Germanium and silicon versions

The original circuit's clipping comes from a pair of germanium diodes: the General Guitar Gadgets replica specifies two 1N270 germanium diodes at D1 and D2¹. The transistors in the original units were part of a six-transistor circuit¹, and the question of germanium versus silicon comes up mostly in modern rebuilds rather than in distinct factory versions.

Modern makers approach the germanium/silicon split in different ways, which is useful context for anyone comparing fuzzes:

• Jed's Pedals' Grimm Reaper is a silicon and germanium hybrid fuzz¹³.
• Dingotone's Germanium Hybrid Fuzz is a hybrid silicon/germanium circuit¹⁴.
• Tru-Fi's Two Face Fuzz combines two circuits in one unit, a germanium-transistor circuit and a silicon-transistor circuit¹⁵.
• MXR's Hybrid Fuzz combines a silicon transistor and a germanium transistor in a single circuit¹⁶.

The classic Fuzz Face circuit was originally available in two versions using germanium or silicon transistors¹⁷⁷³, which is the pattern most players know; the Super-Fuzz's own story is centered on its germanium diodes and its transistor phase splitter rather than on two factory transistor options.

The many brands that sold the Shin-Ei circuit

The Super Fuzz circuit is one of the most rebranded circuits in fuzz history. SolidGoldFX places it in a distinct era of Japanese and Asian fuzzes: "the Univox Super Fuzz, Ibanez Standard Fuzz, Ace Tone Fuzz Master, Shin-Ei Companion and several others"¹⁸, a list RockBoard's PedalPedia entry for the 76 MKII repeats, calling those pedals fuzz legends of that era¹⁹.

The brands that sold the circuit include:

• Univox, the American brand it is best known by³
• Apollo, Shaftesbury, JAX, Tiesco and Memphis³
• Shaftesbury, Kent, Crown and Jax, among dozens of others Shin-Ei produced circuits for²
• Ibanez, as the Standard Fuzz⁴

Pedals based on the Super-Fuzz

Because the original has been out of production for decades, a steady stream of makers has built pedals on the circuit³²⁷:

Tru-Fi describes its re-creation plainly: "This a re-creation of the Univox Super Fuzz which is a unique aggressive fuzz that is very retro!"¹¹. The Oneder Fuzz's reference to "the Super one, and the Hyper one" points at the circuit's 90s second life, when the Super Fuzz saw a resurgence during the grunge and alternative rock era²⁴³.

DIY layouts and builds

The Super-Fuzz is a well documented DIY project. Guitar FX Layouts publishes a vero (stripboard) layout for the Univox Super Fuzz sized for a 1590BB enclosure, and the builder reports having built it and that it works well²⁵. The layout is drawn for modern NPN silicon transistors with CBE pinout, such as the 2N5088, 2N5089, MPSA18, 2N2222 and 2N3904, so these can slot right in²⁵. One builder's version added a 10k trimmer for the Q4-Q5 octave biasing, a 10k trimmer for saturation control of the diode pair, a 10k mid scoop pot, a 300pF cap on Q6 base-collector, and an SPST switch to bypass the saturation trimmer⁸²⁵. A 1590B friendly version of the layout was planned but had not yet been made²⁵.

The Guitar FX Layouts blog published a vero (stripboard) layout for the circuit in January 2012, sized for a 1590BB enclosure, with a 1590B friendly version planned²⁵. The layout was verified working by builders, one of whom reported in June 2012: "I have built this one, it works good"²⁵. The layout is built for modern NPN silicon transistors with CBE pinout, such as the 2N5088, 2N5089, MPSA18, 2N2222 or 2N3904, so common parts slot straight in²⁵.

Builders have also documented modifications to the circuit, from a 2014 build²⁵:

1. A 10k trimmer for the Q4-Q5 octave biasing.
2. A 10k trimmer for saturation control of the diode pair.
3. A 10k pot for a mid scoop.
4. A 300pF cap on Q6's base-collector.
5. An SPST switch to bypass the saturation trimmer.

GuitarPCB's Fzzz Bxxx board, another take on the circuit family, reports that it "cleans up amazingly well with the twist of your Guitar volume producing powerful chiming clean tones" on the brink of breakup before full fuzz²⁶. That is the maker's claim for its own board rather than a documented property of every vintage unit, but it is the kind of behavior DIY builders of the Super-Fuzz circuit often explore through the mods above.

Pedals on this page

available from Rose-Morris who had a showroom in Shaftesbury Avenue Shaftesbury Duo Fuzz (1968 original)

available from Rose-Morris who had a showroom in Shaftesbury Avenue · Fuzz

Shin-ei Astron FY-6 Super Fuzz

Shin Ei · Fuzz

$398 list price

Ibanez Standard Fuzz

Ibanez · Fuzz

Shin-ei FY-6 Super Fuzz

Shin Ei · Fuzz

$498 list price

MXR Hybrid Fuzz

MXR · Fuzz

$170 list price

Tru-Fi Two Face Fuzz

Tru-Fi · Fuzz

$209.95 list price

SolidGoldFX 76 MKII

SolidGoldFX · Fuzz

Gigahearts FX Hyper Soup

Gigahearts · Fuzz

$213 list price

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