ELECTRO HARMONIX OP Amp Big Muff

ELECTRO-HARMONIX Op-Amp Big Muff Pi Fuzz / Distortion / Sustainer

The Electro-Harmonix Op-Amp Big Muff Pi is a precise reincarnation of the legendary 1978 model. Instead of transistors, this pedal relies on operational amplifiers (Op-Amps) and three (instead of four) gain stages. The result is a unique, more aggressive, and "grittier" sound that is perfect for grunge rhythms and wall-shattering riffs.

One of the most striking features of this model is the Tone Bypass switch. When engaged, the tone circuit is completely removed from the signal path. This not only changes the sound's timbre but also provides a huge boost in volume and power, allowing your guitar to dominate any mix. Although the pedal retains the original circuitry and sound, it is housed in a compact, modern-standard enclosure with True Bypass functionality.

Key Features

• Op-Amp circuit: Recreates the unique sound of the V4 era (late 70s), popularized by Billy Corgan.
• Tone Bypass switch: Allows complete disengagement of the tone control, providing maximum signal throughput and volume.
• Distinctive character: "Crushing" and harmonically rich sound ("wall-of-sound distortion"), ideal for heavy music.
• True Bypass: Ensures signal clarity when the effect is disengaged.
• Compact size: Durable die-cast enclosure, saving space on your pedalboard.

Technical Specifications

• Manufacturer: Electro-Harmonix (EHX)
• Model: Op-Amp Big Muff Pi
• Type: Fuzz / Distortion / Sustainer
• Circuitry: Analog (Op-Amp)
• Bypass: True Bypass
• Connections:
  • 1 x Input (1/4" female)
  • 1 x Amp Output (1/4" female)
• Power: 9V battery (included) or 9.6VDC-200mA adapter (not included, center negative)
• Current consumption: 5 mA
• Dimensions: 114 x 70 x 53 mm (4.5" x 2.75" x 2.1")
• Year of Release: 2017

What's in the box?

• 1 x Electro-Harmonix Op-Amp Big Muff Pi pedal
• 1 x 9V battery
• 1 x User manual

Who is it for?

• Fans of "The Smashing Pumpkins" looking for an authentic "Siamese Dream" tone.
• Guitarists for whom the standard "Big Muff" sounds too gentle or "smooth".
• Musicians who want an aggressive, harmonically rich distortion that cuts through any mix.