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Moogerfooger is the trademark for a series of analog effects pedals manufactured by Moog Music. There are currently eight different pedals produced, however one of these models is designed for processing control voltages rather than audio signal. A sixth model, the Analog Delay, was released in a limited edition of 1000 units and has become a collector's item.


Audio moogerfoogers consist of a black wedge-shaped box, approximately 5 by 9 inches (13 by 23 cm), with walnut edges. The face contains an array of knobs, switches and LEDs. All moogerfoogers have a knob that allows the user to fade the effect from a completely dry (100% original input) to a completely wet (100% processed) signal. There is also a stomp switch that allows the user to toggle the effect on and off and a knob that controls the gain. True to the nature of modular synthesizers, all parameters on the pedals are variable using control voltages which may be plugged into the rear of the pedal using 1/4" jacks.


The MF-101 is an independent analog low-pass filter. Based on the amplitude of the dry audio signal, an envelope is generated. This envelope alters the filter's cutoff frequency and its amount is variable. Knobs also allow controlling of the filter's frequency (from 20 Hz to 12 kHz) and resonance. The resonance can be increased to the point of self-feedback producing a pitch that follows the filter cutoff frequency. The MF-101 was released by Big Briar (now Moog Music) in 1998.


The MF-102 is an analog ring modulator. This moogerfooger heterodynes the dry audio signal with a carrier wave that is generated by an internal oscillator. The user can vary the frequency of the carrier oscillator from 600 mHz (0.6 Hz) to 4 kHz. The MF-102 also features an independent low frequency oscillator (LFO) that changes the frequency of the carrier oscillator. The user can select the frequency (from 100 mHz to 25 Hz) of the LFO and whether the signal is a square or sine-like (really a triangle) wave. The user can also vary the amount, if any at all, which the LFO affects the carrier frequency. Like the MF-101, the MF-102 was released in 1998.


The MF-103 is an analog twelve stage phaser. The user can control the "sweep" which moves the phaser's frequency response, yielding the classic phaser "whooshing" sound. The user can switch to 6-stage mode to produce a subtle change in harmonic response. The user can also control the phaser's resonance, changing the height and sharpness of the phaser's frequency response peaks. Like the MF-102, the MF-103 has an independent LFO, however in this instance it is used to vary the "sweep" parameter. The MF-103 was released in 1999.


The MF-104 is a completely analog delay. The effect allows the musician a delay time between 40 milliseconds and .8 seconds. However the most remarkable feature is the use of an internal/external feedback loop. The feedback loop from the MF-104 could be routed through another effects processor and back into the delay unit, allowing processing of the echos as they are being generated. As with most analog delay processors, a desirable warmth of sound is created by the increasing natural decay of the original audio signal through the continuation of echoes.

Released in 2000, the MF-104 was manufactured in a limited edition of 1000 units. A special "bucket brigade delay chip" was employed to allow the effect to be completely analog, however the supply of these chips was limited. The final units were sold in 2001 and the MF-104 Analog Delay remains the most sought-after of the moogerfoogers. In 2005, Moog Music announced the planned re-release of the MF-104, dubbed the MF-104Z. The new pedal will have the same functions as the original, but will feature a longer possible delay time (slightly longer than 1 second). At the same time, the MF-104SD was released in a limited edition of 250 units. The MF-104SD had a maximum delay time of 1.4 seconds, slightly longer than the MF-104Z.

In June 2012, Moog Music Inc. released the fourth and final version of their Moogerfooger Analog Delay, the MF-104M. The new MF-104M Analog Delay utilizes the same vintage Bucket Brigade chips found in the Classic MF-104. In addition, the MF-104M includes a number of customer requested feature and function upgrades. “We’re very excited about this limited release of the MF-104M,” said Moog Music CEO, Mike Adams. “Many of the parts we use to create these amazing delays are completely original and incredibly hard to find. Since this will be the last of its kind, we have gone to great lengths to incorporate features and functions requested by customers over the last 12 years. The MF-104M delivers those rich, creamy, classic delays Moog is renowned for, but also has the ability to modulate the delay time and create effects not found in any other analog delay."

The MF-104M recreates the sound of the original MF-104. It uses 4 MN3008s, which provide 800ms of analog delay. A new 6 Waveshape LFO significantly expands the sonic capabilities of this Classic Analog Delay. The MF-104M incorporates Spillover Mode, the most popular modification to the Classic MF-104. A Tap Tempo switch lets users quickly tap in delay times or LFO rates, and MIDI capability allows control over every function. The rear panel contains ports for additional pedal inputs, to control other parameters.


Better known as the MuRF, the MF-105 or Multiple Resonance Filter Array is an original effects processor, designed by Bob Moog in 2004. The MuRF has 8 band-pass filters whose levels are controlled by 8 sliders which resemble a graphic EQ. The filters' center frequencies are set at 200 Hz, 300 Hz, 450 Hz, 675 Hz, 1 kHz, 1.5 kHz, 2.2 kHz and 3.4 kHz and their sliders adjust the gain of each filter. The Bass MuRF or MF-105B, designed for bass guitar players, has slightly lower center frequencies of 110 Hz, 160 Hz, 240 Hz, 350 Hz, 525 Hz, 775 Hz, 1.2 kHz and 1.8 kHz. In addition, the 110 Hz filter was changed to a low-pass filter.

The gain of each filter is further controlled by an envelope that is triggered by any of a number of preset animation sequences. The user can select one of 24 animation patterns. Rhythmic variations can be created by adjusting the levels of the filters, speed of animation, and envelope amount.


The FreqBox or MF-107 was added to the moogerfooger series in early 2007. It was not designed by Bob Moog and it was the first new stomp box to be produced by Moog Music after Bob Moog's death. In general the FreqBox sounds similar to a synthesizer because its interior is actually a VCO that is modified by the input signal.

On the left hand of the box the FreqBox contains a VCO which has two knobs to control frequency and waveshape. The waveshape runs from triangle wave to sawtooth wave to square wave to pulse wave. There is a hard sync on/off switch that turns on hard syncing the VCO signal with the input signals frequency. The amplitude of the VCO is controlled by the amplitude of the input signal.

On the right hand side there are three knobs. A mix knob to mix the level of input signal with the level of the VCO signal, a FM Amount knob that allows the input signal to modulate the VCO with frequency modulation, and an Env. Amount knob that sets an envelope to the frequency modulation.


The "Cluster Flux" was announced June 15, 2011.


The CP-251 is a control voltage processor that is designed to be used with any of the moogerfoogers or any other audio device that can be manipulated with control voltages. It does not process sound, only the voltages that control the various parameters on other audio equipment. The control voltages act as invisible hands which "turn" the knobs and controls on the other gear. The CP-251 has a total of 9 knobs and 23 quarter-inch jacks.

The CP-251 features an LFO with adjustable rate and square and triangle outputs, a lag processor that can alter the rise and fall of a signal, a multiple jack that passively joins four patchcords together, a white noise generator, two attenuators, a four-way mixer that can process four signals into one, and a sample and hold. The sample and hold samples a voltage (the noise source) every time a trigger voltage (the square LFO) crosses the threshold. The sampled voltage appears in the output. The user can also use alternate sample and/or trigger voltages to produce desired effects.

The 4'33"

In late March 2005 Moog Music's website announced a new moogerfooger as an April Fool's Day joke. The moogerfooger 4'33" supposedly had only one button, which would silence any inputs for exactly 4 minutes and 33 seconds. The name and function of the unit was a reference to John Cage's famous composition 4′33″.


On April 1, 2009 Moog Music's website announced another new moogerfooger as an April Fool's Day joke. The MF-106TC Analog Time Compressor supposedly had the ability to compress the time stream rather than expanding it like a delay pedal, which would then give musicians the ability to hear notes before they actually played them.

Software plugins

In 2000, digital effects recording studio Bomb Factory worked with Bob Moog to develop music plugins for Pro Tools based on the MF-101, MF-102, MF-103 and MF-104. The plugins allowed the user to replicate the effects of the moogerfoogers while editing or processing digital audio on their computer.


Moogerfooger Wikipedia

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