Electro Harmonix Ram's Head Big Muff Pi Distortion Fuzz Sustainer Pedal

Product Information

The Russian Muffs are coveted by bassists and heavy players for their big, boosted low end. They are very smooth and have slightly less gain than the other Muffs. If you’re worried that a vintage Russian has some special unobtanium in it, don’t be. These circuits are identical to the 90s versions. V2 Rams Head Big Muff - The high pass resistor value started with 33k, which was the most common value. 22k was the second most used, but there were also some variants that used 39k. In general terms, the new Ram's Head is growlier in the midrange than most Russian-style Muffs (which are famously extra-scooped and wooly) and “triangle" versions (which are often more focused, fizzier, and white-hot in the high-mids). Sustained single notes are smoother and more sonorous than the output from triangle versions, and tend to split the difference between a triangle's silicon fizziness and a Russian-type's cabernet-smooth contours. It marks an absolute sweet spot, in my opinion, and a reason for Animals-era Gilmour fans to take note. The Pete Cornish 1979 Wall studio board featured a ram’s head Big muff. The circuit was most likely modified to sound like David’s #1 ram’s head. The board was later used for the About Face and Division Bell recording sessions and possibly also The Final Cut sessions David at least used a Big Muff on the sessions.

REPLACEMENT SLIDE SWITCHES - Power and tone bypass switches on vintage USA Big Muffs are Alpha Slide DPDT 90 size. Small Bear Electronics carries Big Muff replacement switches. V3 BIG MUFF PI with TONE BYPASS - The very first circuit mod by EHX. A rare variant of the V3 circuit with tone bypass switching (C15, R28, switch) and power filtering (R27, C14), made simultaneously with the V4 and V5 op-amp versions. Many people think the tone bypass was added with the V5 Big Muff, but it actually first appeared in this V3 variant, circa 1979. It was simple switch in between C14 and C3 that completely bypassed the Big Muff tone control, making the tone pot inactive, flattening the EQ, and giving a slight volume boost. This variant used MPSA18 transistors, very rarely used in a BMP. ACE TONE FUZZ MASTER FM-3 - A rare early clone of the V1 Big Muff, circa 1971-73, and one of the first modified BMP circuits. This is a little known clone, often mistakenly thought to be a variant of the Roland Bee-Baa circuit. Ace Electronic Industries was founded by Ikutaro Kakehashi, who later founded Roland in March 1972. Prior to that Ace made the FM-1 which was a Maestro FZ1-A clone, and the FM-2, which was a Univox Super Fuzz clone, and the FM-3, possibly the first Japanese Big Muff clone. It was a very unique version of the circuit, incorporating a switchable volume boost stage (shown in red), allowing switching between distortion and boost (sadly, not combinable), with separate volume and tone pots for each.

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That’s my sound. The Muff is always on,” J says. “All distorted sounds begin with the Muff. That’s what I grew up playing so it’s kind of amazing to have my own signature one.” Shown above: V2/3/4/5 Muffs all used Daka Ware style pointer knobs with D shafts. They are still being made by Davies Molding at the time I write this (2011) and can be found online, Davies model #1470. There is a D shaft version (Small Bear #0803M) and an identical version with a set screw in the side (Small Bear #0803), so it works on D or round shafts. OEM replacements for those can be found at Small Bear Electronics. Pedal Parts Plus also carries replacement knobs that can be used. Note that most vintage Big Muffs had D shaped posts, so D shaped post holes or knobs with round holes and a set screw are necessary. Remove your knobs to see which type you have. COLORSOUND SUPA TONEBENDER Modified Violet Ram's Head Big Muff - Around 1973 Sola Sound of London decided to clone the Big Muff for their Colorsound ToneBender line. The component values were copied from a 1973 violet era Big Muff, similar to those shown above, but with one major change. The coupling caps and clipping diodes in the first clipping stage were removed, making a very unique sounding Big Muff, and one that is very much fitting with the Tone Bender family of sounds. I have an early circuit board in my Supa that actually includes through holes in the first clipping stage for the missing cap and diodes, indicating Sola intended to originally make a straight clone of a violet Big Muff, or possibly had plans to do so later, but it does not appear any were made with the complete components. There is also an extra .1µF cap in the tone section at C14, and a polarized electro added to the 9v for power filtering, not found on the original violet BMP circuits.

REPLACEMENT POTS - Vintage USA Big Muffs (V1, V2, V3) have single-gang, linear taper, 24mm,100k potentiomers. Electro-Harmonix used pots from various makers, but they were usually the 24mm size, with 1/4" D shaped knob shafts. 250k linear can be substituted for the volume and sustain pots if 100k are not available. 100k Logarithmic taper pots, or "audio" pots, will also work, but they are more expensive than linear, and the useful volume range gets squeezed into a smaller area of the knob rotation. The difference between linear and logarithmic/audio pot types is that linear increases (electrical resistance) evenly as you turn the knob, whereas log has a shorter increase at both ends of the knob rotation, but a longer, increase in the middle. That that wider spectrum in the middle means a more usable range to allow better fine tuning with a log pot, in a tone knob for example, but not the best for a Big Muff volume pot. Both types sound the same, but the knobs will be in different positions for the same volume, tone, or gain level. A RESISTORS - Electro-Harmonix used cheap carbon resistors throughout the 1970's (the fat dark brown cylinders with color bands), gradually switching to carbon composition type (smaller cylinders with fatter ends, and various case colors - tan, light brown, dark brown, red-brown) in the late 1970's and early 1980's. When the Big Muff returned to production in 2000 carbon composition was again used, with occasional use of some modern carbon film or metal film resistors (similar to carbon composition, but case color is usually blue) appearing in later years. What is the difference? Carbon and carbon composition resistor tolerances (electrical variance from part spec to actual measurement) are very high and film resistor tolerances are lower and more consistent from part to part. Some also claim film resistors are lower noise in audio circuits than carbon types. Having owned many Big Muffs with both types, and a few clones of the exact same circuit with all of one type, and all of the other type, I hear absolutely no difference in the level of noise between the two.

Technically the Big Muff is not a fuzz but closer to a distortion. Sonically though, its tone is perhaps closer to a silicon transistor fuzz than a DS1. As a rule of thumb, and for authentic David Gilmour tones, I would say fuzz for 1968-75 and Muff from 1977 to present.

Since some wall warts (AC to DC power adaptors) do not regulate and filter properly it was necessary for E-H to add some filtering to the circuit. Wall warts convert AC to DC using a bridge rectifier, but some of that rippling alternating current can still leak through the power supply rail into the direct current, creating 60 cycle hum noise in the audio signal. The 100Ω resistor at R27 is there to reduce that noisy AC. AC current sees a capacitor as a short circuit, so the big electrolytic cap on the +9v power supply at C14 was added to smoothly filter more of the AC ripple by draining the ripple peaks to ground, leaving (mostly) straight DC going through the circuit. Using a booster while recording is not a good idea because it’s often hard to tame both the increased gain and the noise caused by blending two gain effects. To get that same smooth, compressed Big Muff tone, David would play incredibly loud to get the amp’s tubes really hot. This was something he also would do to smooth out the even harsher fuzz pedals in the early 70s during the recording of Meddle and Dark Side of the Moon. As described above, mic placement and additional compression, limiting and EQ is also crucial to manipulate the tone. HOHNER TRI DIRTY BOOSTER - Another very good clone of the BMP. This one appeared on the market around 1974 or '75 from Hohner. Component values are similar to a few V1 schematics, but it does not follow any of them exactly. An extra .022µF cap was added in the tone section between lug 1 of the tone pot and R8, presumably to widen the tone pot sweep, although I hear little difference when it is removed. The most coveted of all the Muffs, the early 70s Ram’s Head was used by David Gilmour for his epic, singing lead tone. The Ram’s head is articulate and very loud, with a bit of vintage “spittiness.”Note that the original Silicon diodes are marked SYL GY920, but the actual diode types used are unknown. 1N914 (shown on the schematic) and 1N4148 are some modern equivalents that work, but they may not be identical to the original diodes. The differences are minor, but diode types do affect the sound frequencies that are clipped. Ram's head = very similar to Russian but it has less definition and goes more towards OG triangle in terms of mud. Still very powerful and bassy The Nano takes the NYC model and shrinks it down to pedalboard-friendly size. Does it sound any different? Maybe. But not nearly enough to make a meaningful difference. Adjusting the Nano’s tone and sustain will get you the same range of sounds as its big brother. When EHX started building Muffs in the late 60s, the circuit was not standardized and any two Triangle Muffs could sound different. EHX referenced two vintage models to create this reissue, and successfully captured the bite and gated unpredictability of these early units. VERSION 3 BIG MUFF PI - Approximately 10 circuit variants exist, each made in extended manufacturing runs.