Sunn O))) Life Pedal Octave Distortion + Booster

Whether or not you are a fan of the band Sunn O))), this unique distortion/boost/fuzz/octave pedal by EarthQuaker is worth checking out if you are in search of heavy-osity.

The Story

Birth of a Life Pedal

In the writing sessions for Life Metal Stephen O’Malley and Greg Anderson of Sunn O))) worked extensively shearing their tones toward a broader energy spectrum over high powered saturation and across planes of sonic character, with the ambition to take full advantage of recording engineer Steve Albini’s exacting capture skills.

The Life Pedal is designed to represent the core front end chain used in those sessions, by driving the tubes of the band’s amplifiers into overload ecstasy. This is a 100w tube amp full stack’s holy dream, or its apostate nightmare.

An octave fuzz inspired by the Shin-Ei FY2 and FY6 units leads the circuit into a LM308 chipped and big box Rat-like distortion, recreated with the best components. It includes a three-way clipping switch with op amp, asymmetric, and symmetric settings. The second stage is pure clean boost to further overdrive the preamp tubes of your system into harmonics and feedback overtones.

What Is It?

Life Pedal is a distortion with a blendable analog octave up and a booster combined in one compact package. The “Amplitude” side is faithfully modeled after the classic “White Face” distortion unit, right down to the LM308 IC and tantalum caps. The only modifications made to the original circuit are in the clipping section. The traditional circuit uses a single pair of silicon diodes for a tight, compressed crunch.

The Life Pedal introduces two additional clipping options to better adapt to different rigs. The first position is no diodes to allow for full, grinding Op Amp assault at maximum volume. The second position utilizes two silicon diodes and one LED in an asymmetrical clipping configuration. This delivers a slightly compressed and smooth crunch, similar to a valve amplifier. The last position is the stock double silicon diode configuration which provides classic tone.

The Octave in Life Pedal is an all-discrete, analog full-wave rectifier circuit built around a pair of Russian Germanium diodes. Located at the input of the circuit, the Octave control slowly blends in the octave effects as you turn it clockwise. This feature can also be used via expression control allowing for wild, hands-free octave swells mid-riff. Because this is an analog octave effect, it is monophonic and works best playing single notes above the twelfth fret while using the neck pickup. Playing chords with the analog octave will sound clanging and chaotic (not necessarily a bad thing). Using the bridge pickup and playing below the twelfth fret will produce a very subtle octave effect. Going full Octave transforms Life Pedal from a simple distortion device into a swelling, raging fuzz similar to the classic Super Fuzz.

The “Magnitude” section of Life Pedal is a simple all-discrete MOSFET booster. It is 100% clean and high impedance, adding very little color to your tone. It does not add distortion on its own but has plenty of output to push your amp into saturation.

The signal path goes Octave>Distortion>Boost. The octave distortion and booster can be used independently with their own respective footswitches. The Petrine Cross is the octave distortion and the Christian Cross is the booster.


  1. Amplitude: Output volume for the octave distortion side. Clockwise for more hearing loss, counterclockwise for a healthy life in old age.


  1. Filter: This is a low pass filter with a frequency response from around 500Hz to 30kHz. Turn counterclockwise for more high-end, clockwise for less.


  1. Distortion: Turn clockwise for more distortion, counterclockwise for less. This provides about +60dB of gain.


  1. Magnitude: This is the output volume for the booster. Clockwise to blow up your amp, counterclockwise if you are a baby. Unity is somewhere right around noon on the dial.


  1. Octave: This blends in the analog octave as your turn it clockwise.


  1. Octave EXP: Connect any expression pedal to this input to control the analog octave blend. Before inserting the expression pedal, make sure the pedal is powered off.


  1. Left Footswitch: Boost Activator


  1. Clipping Switch:

OpAmp- No diodes to allow for full, grinding Op Amp assault at maximum volume.

Asymm- Utilizes two silicon diodes and one LED in an asymmetrical clipping configuration. This delivers a slightly compressed and smooth crunch, similar to a valve amplifier.

Symm- This is the stock double silicon diode configuration which provides that classic tone you know and love.

  1. Right Footswitch: Octave Distortion Activator


List Price: $269.00

Measures:  4.65 x 3.65 x 2.25 in. (118 x 93 x 57 mm) with knobs

Current Draw: 15 mA

Octave Distortion: Input Impedance: 1 MΩ /

Output Impedance: <1 kΩ

Booster: Input Impedance: 500 kΩ /

Output Impedance: <1 kΩ

Flexi-Switch® Technology

This device features Flexi-Switch® Technology! This relay-based, true bypass switching style allows you to simultaneously use momentary and latching style switching.

For standard latching operation, tap the footswitch once to activate the effect and then tap again to bypass.

For momentary operation, hold the footswitch down for as long as you’d like to use the effect. Once you release the switch the effect will be bypassed.

Since the switching is relay based, it requires power to pass signal.


This device takes a standard 9-volt DC power supply with a 2.1mm negative center barrel. We always recommend pedal-specific, transformer-isolated wall-wart power supplies or multiple isolated-output supplies. Pedals will make extra noise if there is ripple or unclean power. Switching-type power supplies, daisy chains and non-pedal specific power supplies do not filter dirty power as well and let through unwanted noise. DO NOT RUN AT HIGHER VOLTAGES!



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