Lost ’70s Circuit Reborn: Electro-Harmonix Unveils the Bass Big Muff Pi 2

Electro-Harmonix (EHX) has announced the release of the Bass Big Muff Pi 2. This new fuzz pedal resurrects a “lost” dual op-amp circuit from the late 1970s, rediscovered by Josh Scott of JHS Pedals, and re-engineers it specifically for the low-end thump of the bass guitar.

A Historic Discovery in a Notebook

The story behind the Bass Big Muff Pi 2 reads like a treasure hunt for tone fanatics. The circuit traces its lineage back to the collaboration between EHX founder Mike Matthews and legendary circuit designer Bob Myer. While the duo created the original Big Muff, Myer tucked away a dual-op-amp design in his personal files in the late 70s—a design that never saw the light of day.

Decades later, during a visit to Myer’s workshop, Josh Scott (JHS Pedals) and Daniel Danger discovered the hand-scrawled schematic among old notes. Scott decoded the design, which EHX initially released as the guitar-focused Big Muff Pi 2. Now, that same grit has been optimized to handle the frequency range and dynamic needs of modern bassists.

“Woolly” Tone Meets Modern Control

The Bass Big Muff Pi 2 is described as delivering a “woolly, radical ram’s head character” with less-refined clipping than standard Muffs, offering a more aggressive, open distortion.

While the pedal maintains the classic Volume, Tone, and Sustain trio, it introduces features critical for bass signal management:

• Blend Control: Allows players to mix their dry signal with the fuzz, ensuring the fundamental note remains distinct even under heavy distortion.

• Bass Boost: A toggle to inject low-end heft, preventing the “thinning out” that often happens when cranking the tone knob on fuzz pedals.

Performance Flexibility

Beyond the tone, EHX has modernized the user experience. The pedal is housed in a road-tough, space-saving Nano enclosure. It features silent true bypass switching to preserve signal integrity when disengaged.

Perhaps the most unique performance feature is the dual-mode footswitch. It supports both standard latching (on/off) and momentary operation. By holding down the footswitch, bassists can unleash short bursts of “fuzzy discord” for accents and fills, automatically bypassing when the foot is lifted.

FAQ: The Bass Big Muff Pi 2

Q: What is the difference between this and the standard Bass Big Muff?

A: The primary difference is the circuit architecture. The Bass Big Muff Pi 2 uses a specific dual-op-amp design from the 1970s that provides a different clipping texture—described as “less refined” and grittier—than the transistor-based circuits of standard Muffs.

Q: Who is Josh Scott, and why is he involved?

A: Josh Scott is the founder of JHS Pedals. He is credited with discovering the original hand-drawn schematic for this circuit in designer Bob Myer’s old notes and helping to “decode” and optimize the design for modern release.

Q: Does the pedal cut low-end?

A: Fuzz pedals notoriously cut low frequencies, but the Bass Big Muff Pi 2 solves this with two specific tools: a Blend knob to mix in your clean low-end signal, and a dedicated Bass Boost switch to pump up the bottom frequencies.

Q: How does the momentary switch mode work?

A: If you tap the footswitch, it works like a normal pedal (on/off). However, if you hold the footswitch down, the effect engages only as long as you hold it, turning off immediately when you let go. This is ideal for quick stutter effects or brief moments of chaos.

Q: Will this fit on a crowded pedalboard?

A: Yes. The pedal uses Electro-Harmonix’s standard “Nano” die-cast chassis, making it compact and pedalboard-friendly.

Guitar BombVerdict

The Electro-Harmonix Bass Big Muff Pi 2 is more than just another dirt box, as it combines the “lost” vintage grit of Bob Myer’s 1970s dual op-amp design with modern necessities like a dry blend and momentary switching, It could be great for lots of music styles, and I think it sounds better than the Big Muff Pi 2 in some ways, because of that blend.

EHX has created a versatile tool for bassists. Whether you need low-grade grit or a full-blown wall of fuzz, the Bass Big Muff Pi 2 promises to deliver the legendary sustain EHX is known for, without sacrificing the floor-shaking low end that bass players require.