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Electro-Harmonix Germanium 4 Big Muff Pi Pedal Review

Electro-Harmonix Germanium 4 Big Muff Pi Pedal Review

A dual-germanium transistor Big Muff Pi pedal alongside a dual-germanium transistor overdrive pedal

Download Example 1
Bypassed, then Overdrive side. Gain dimed, Bias - 9, Tone - 1, Volume - 10. Fender Strat, neck pickup.
Download Example 2
Overdrive side, then both sides. Fender Strat, bridge pickup.
Download Example 3
Volts and Bias dimed, Gain - 12, Volume - 10. Gibson SG, bridge pickup.
Download Example 4
Gated Lo-Fi Tone. Volts - 7, Bias dimed, Gain - 2, Volume - 12. Gibson SG, neck pickup.
Clips recorded with the clean channel of a Budda V-40 Superdrive II 2x12 combo and Shure SM57.
The origins of the Germanium4 Big Muff Pi can be traced to Mike Matthews and Robert Myer’s early Electro-Harmonix-branded creations. One of their very first effects, 1968’s LPB-1 linear power booster, ushered in the age of overdrive and is still in production to this day. Next came the small, two-transistor Muff Fuzz pedal, named as such because of its “funky, soft, muffled sound.” Myer was asked by Matthews to modify this pedal, and the result was a larger, bigger-sounding fuzz pedal. This pedal had loads of sustain with a very smooth frequency spectrum and a huge bottom end, almost as if a fuzzy sub-octave were present—witness the Big Muff Pi.

Today, Electro-Harmonix has more than ten pedals under the “muff” umbrella, the latest of which, the Germanium4 Big Muff Pi, places a dual-germanium transistor Big Muff Pi pedal alongside a dual-germanium transistor overdrive pedal (2 + 2 = G4). The resulting stompbox stacks the best of both worlds - vintage analog overdrive and vintage analog distortion, which can be used independently or simultaneously (overdrive follows distortion when both are engaged).

All Grown Up
Those who are already familiar with the Big Muff will quickly notice that the typical big silver chassis has been ditched, in this model, for the standard rectangular box common to most of EHX’s recent releases. The pedal’s khaki, psychedelic graphic is bisected to indicate the presence of two independent, true-bypassed pedals. I am personally fond of this standard approach to the layout of EHX pedals as it affords the footswitches plenty of space, standardizes the layout across their product line, and offers a clear presentation of the control knobs along the top-front of the chassis. The chassis itself is rugged, as are the jacks and footswitches. The black control knobs are comfortable, low against the chassis, and have plenty of mechanical resistance. 9-volt battery power will run the G4 as will the optional Boss/Ibanez compatible DC adapter.

Overdrive Side
The Overdrive controls include Gain, Bias, Tone, and Volume. Plugging in my Fender Strat, engaging the overdrive side, and starting with a low Gain and a high Volume setting, the pedal produced a nice, fat clean boost. Rolling up the Gain increased the driving warmth until, at full clockwise, the pedal rang with a jammin’ classic rock tone. The Tone knob changes the mid frequency emphasis from throaty low-mid at counter-clockwise to edgy high-mid at clockwise.

In my opinion, the most impressive feature on this side of the pedal is the Bias control, whose results are similar to the response of a bias adjustment on a tube amp. As the Bias is decreased, the signal becomes compressed, from subtle to a breathy squish in response to picking dynamics. The unity setting produces the raw, uncompressed, punchy signal. At clockwise, a fair amount of gritty gain is added to the signal. Even just on this side of the pedal the possibilities are broad. The G4 responded differently—with more gain and a smoother, unified overdrive—to the humbucking pickups in my Gibson SG.

Distortion Side
On the right side of the pedal you’ll find four controls: Gain, Bias, Volts, and Volume. Working in conjunction, the Gain and Volume knobs are able to produce a great level of boost, adding (if you desire) the color of your amp’s preamp tubes to the delicious equation of fuzzy, creamy distortion. The Gain knob produces a smooth signal that starts with an edgy overdrive and extends to a full-on gritty wall of fuzz.

The Bias knob on this side of the pedal works a bit differently than the one on the Overdrive side. You can think of it like the threshold control on a compressor. As you bring the Bias knob down the signal becomes more compressed, and as you roll it toward- the clockwise position the signal’s dynamics are fully revealed. I own several B.K. Butler designed Tube Works Real Tube racks for a number of reasons, one of them being the inclusion of a similar bias control. Wrapped up in this control is a wealth of tonal versatility. It is controls like these that should excite fans of the standard Muff.

EHX ditched the Tone control on the Distortion side of the G4, but I feel it would have been nice to have a bit of frequency shaping on this side as well. If you really need to, you can engage the Overdrive side on a clean setting and use its Tone control. In any case, even my Fender Strat’s twangy single-coils were able to produce a robust low end and a dynamic distortion tone.

Lastly, the Volts knob adjusts the voltage level fed to the Distortion side—full voltage at clockwise and low voltage at counter-clockwise. When completely starved for voltage, the pedal produces a gated, lo-fi, 8-bit videogame console-style distortion common among fuzz pedal builders like Devi Ever and Dwarfcraft but an unexpectedly awesome feature from a Big Muff Pi! At full voltage the G4 produces the expected rich Big Muff-style tones.

With both sides of the pedal engaged, the G4 produces even more tonal possibilities through the interaction of two dual-germanium gain circuits. Since the Overdrive follows the Distortion, you’re able to use the Overdrive to either tame the Distortion with the Tone control or tease more distortion from it by stacking another level of gain. As mentioned before, you can engage the Overdrive side and use its Tone control to shape the mid-frequency emphasis of the Distortion side. The shaping possibilities go on and on.

Final Mojo
The two-pedals-in-one design, quartet of germanium transistors, and Bias and Voltage controls make the G4 the most versatile pedal under the Big Muff umbrella. I definitely recommend it to those who are already love the Big Muff and are looking to see it through a new lens. New users, looking to get in on the ground floor with their first Big Muff, will likely enjoy the versatility that the G4 affords.
Buy if...
you’re in the market for a more versatile version of the classic Big Muff Pi.
Skip if...
you’ve got no need for the warm fuzzies.

Street $99 - Electro-Harmonix -

Tone Games 2010, Bonus Levels: 10 More Stompboxes Reviewed
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