Germanium 4 Big Muff Pi Distortion/ Overdrive

Combining four classic germanium transistors, the Germanium Big Muff Pi is the result of a focused modern design dripping with EH analog heritage. An independent overdrive and distortion each have their own sets of two germanium transistors as well as independent controls. The ability to stack and use both the overdrive and distortion together delivers the power of a four germanium transistor circuit with ultimate control flexibility.

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Quick Specs
Individual overdrive and distortion with the ability to stack them together
4 individual Germanium Transistors
Each mode of drive mode uses its own 2 germanium stack
Overdrive and distortion can be stacked utilizing four germanium transistors
Bias and tone control define the tonality in overdrive
Volts and Bias define the way the distortion will react
Starving battery sound through volts control adds character
Battery equipped with optional 9.6DC-200 power supply
Dimensions in inches: 4.75 (w) x 5.75 (l) x 2.5 (h)
Dimensions in mm: 146 (w) x 121 (l) x 64 (h)
From the Blog
Posted 9/1/2016

"EHX’s Germanium 4 Big Muff Pi is a veritable playground of tone sculpting possibilities for the tireless germanium fanatic. It’s a great pedal, and it’s pretty damned cheap. Get one!" | Tone Report Weekly

Click here to read the full review.

Posted 5/25/2016

Here's one way to stack your Big Muffs... from Muff Low.

Posted 5/23/2016

Eric M. has a great collection of new and vintage Big Muffs!

Posted 3/17/2014

Happy St Paddy’s Day from EHX. Here’s Bill Ruppert’s Effectology video showing how he turns a guitar tone into a tin whistle.

Posted 11/11/2013

Pro Guitar Shop reviews the Germanium 4 Big Muff Pi.

Posted 9/9/2013

Robert Baker rocks hard with the Germanium 4 Big Muff Pi.

Posted 5/2/2013

Germanium is an element like carbon or gold. Germanium transistors were used extensively back in the 1950s and ‘60s. Eventually they were replaced by components that were considered “better.”  The EHX Germanium OD and Germanium 4 Big Muff Pi use these old school transistors. They have a distinctive sound, some say smoother or “spongier.” You be the judge, hear the Germanium OD here.


Posted 12/26/2011 shows of the versatility of the Germanium 4 Big Muff Pi which features Distortion and Overdrive sections that can be used independently or stacked.

Posted 9/26/2011

StreetSpirit008 demos the EHX Germanium 4 Big Muff Pi.

Posted 5/19/2011

Posted 5/4/2011 does a great job of demoing the Germanium 4 Big Muff Pi.

Posted 3/17/2011

St. Paddy’s Day 2011

Bill Ruppert breathes in the dew of a fine morning in old Eire. With a sly wink and a nod, Bill recreates the mystery of the old Ireland using a little Elvin magic and the power of EHX pedals. 
Learn the secrets of creating lush string synthesizers and Irish tin whistles, using just a regular guitar and Electro-Harmonix effect pedals.

Please note: Bill will be in the EHX Forums to discuss his sounds, settings, and process. We hope you join us there.

Previous episodes:

Stay tuned, more Effectology episodes coming soon!

Posted 2/28/2011

Scorpguitar79 contributed this video of his EHX Germanium 4 Big Muff Pi.


Posted 12/14/2010

The new Germanium 4 Big Muff Pi is reviewed in the February 2011 issue of Vintage Guitar magazine. Their conclusion? “The Germanium 4 Big Muff Pi is the most versatile version in the pedal’s lineage, and does its predecessors proud.”

Click here to read the full review

Posted 12/3/2010

Guitar slinger, Dave Weiner, took time out from his busy schedule to create this in depth, guided tour of the hot new Germanium4 Big Muff Pi.

See more of Dave at his website:

Posted 11/22/2010

Gearmandude demos the Germanium 4 Big Muff Pi.

Posted 11/17/2010

Guitarist magazine recently reviewed the Germanium 4 Big Muff Pi and the Freeze. They said the Germanium 4 Big Muff Pi delivers, “separate overdrive and distortion for the price of a single stompbox…” and described the Freeze as, “a creative idea that can add a really interesting new dimension to your playing.”

Click here to read the full review

Guitarist choice Award

Posted 11/15/2010

Premier Guitar just reviewed the Germanium 4 Big Muff Pi and said it “stacks the best of both worlds - vintage analog overdrive and vintage analog distortion.” 

Click here for the full review

Posted 10/29/2010

Posted 10/26/2010

Music Radar delivers the bottom line on the latest member of the Big Muff family - the Germanium4 Big Muff Pi.

“This Germanium4 Big Muff Pi is one of the more versatile of the lot!” It offers not only two distinct drive and distortion setups but it utilizes two uniquely different control panels. Use individually or stack them together for ultra-powerful, pure germanium analog edge and drive.

Click here for the complete review

Germanium 4 Big Muff Pi

Posted 9/28/2010

Posted 9/7/2010 says, Electro-Harmonix Germanium 4 Big Muff Pi. “Double Your Pleasure. Double Your Gain.”

Click here for the complete review

Germanium 4 Big Muff Pi

Posted 8/23/2010

Mike and Matt put the ultra-versatile Electro-Harmonix Germanium 4 Big Muff Pi through its paces.

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