Op-Amp Big Muff Pi

Product Information

Fuzz pedals operate in the same wheelhouse as overdrive and distortion pedals, in that they use transistors or op-amps to clip your guitar signal, creating distortion. However, while an overdrive pedal might just give your signal some light soft clipping, fuzz pedals almost always use much harder clipping for your signal. The pedal was created by Ivor Arbiter in the mid ’60s, a period which saw a Cambrian explosion of distortions and fuzzes. Many fuzzes had similarities in topology, and the Fuzz Face isn't exempt, being a shunt-series amplifier that resembles the Sola Sound Mark 1.5 Tone Bender. Howard Davis, Manager of Analog Circuit Design for E-H from 1976-1981, claims credit as the circuit designer for this version, as does former EHX designer Michael Abrams. Howard was responsible for over a dozen E-H pedal circuit designs, as well as most the the ”deluxe“ Electro-Harmonix models that appeared in the late 1970s to early 1980s, including the superb op-amp Deluxe Big Muff, Deluxe Memory Man, and Deluxe Electric Mistress. The op-amp Big Muff was assigned to Howard to fill a desire for a simpler, less costly product that would do all that the transistor version did. However, due to the differing distortion characteristics of the op-amps it turned out to have a somewhat "grungier" sound than the transistor design, an effect preferred by some musicians. The circuit was made with one of the popular 741 op-amps and one RC4558 dual op-amp, though occasionally V4 Big Muffs are seen with different chips. Howard's original design schematic, dated 4/6/1978, included the tone bypass switch, seen on the V5 Big Muff. He does not recall ever designing a non bypass version, but sometimes changes were made to his designs by others at E-H that he was not made aware of, which may explain why the V4 version did not include the tone bypass function. The feature was included on the Version 5, which was likely made at the same time as this version, based on the fact that they both share three of the four diferent circuit boards used, and similar pot dates. If you’re looking for versatility and variety in your fuzz tone, this pedal has got you covered. 7. Dunlop Fuzz Face Mini (Silicon) To me the Big Muff pedal changed the entire course of the album (Siamese Dream). That album is a classic album because of a certain way of thinking with this pedal. So when people say “why was this a classic album” and they wanna talk about pain and drugs and Jimmy (drummer Jimmy Chamberlain), the Big Muff is just as important" - Billy Corgan from a 2005 Netphoria interview

Many of these were also made with 1µF polarized electros at C1, C2, and C13, rather than 10µF. Another variant exists with the more common 470pF caps at C10, C11, and C12, but few were made. Polarized electros at C1, C2, and C13 also varied from 1µF to 10µF in that variant. The Electro Harmonix Op Amp Big Muff's circuitry relies on op-amps rather than traditional transistors, along with three gain stages instead of four, to produce its iconic sound. This simplicity was key to making the original so unique and special and that trend is continued with the reissue. The circuitry differences deliver a slightly flatter midrange compared to transistor versions. This, along with the slightly reduced gain levels, deliver the grungier sound these Muffs are known for. Features The sweet, violin-like sustain of the original Big Muff was made using transistors in four gain stages. That tone inspired countless guitarists, including Jimi Hendrix, who bought one of the first units at Manny’s Music on the now-vanished Music Row of Manhattan’s West 48th Street. In each of the clipping amplifiers, the frequency response is similar to the Input Booster, tailored by two capacitors: The input series decoupling caps C 12-C 19 acting as a high pass filter and rolling-off the bass below some decs of Hz and the C 6-C 7 Miller Capacitors acting as a low pass filter shaping the high frequency response and rolling-off around 1KHz: Shown above - V4 op-amp Big Muffs with pots dated 1977. The V4 features an on/off switch and the words ON and Off appear on the graphics, which are identical to the V3 Big Muff. The only way to tell the difference is to examine the circuit board, which will have two op-amp chips rather than four transistors.For this reissue, Electro Harmonix have gone all-out in delivering the same kind of tones that the original Op-Amp Big Muff Pi was famed for. Relying on op-amps rather than transistors, and three gain stages rather than four, the new EHX Op-Amp Big Muff Pi can produce a huge, crushing Big Muff sound with more crunch, that's great for heavy rhythm playing and heavy leads. Pumpkin Pi With original late-70s op-amp Big Muffs now commanding top dollar, Electro-Harmonix founder Mike Matthews decided to reissue the classic pedal at a price players can afford. The new Op-Amp Big Muff Pi is a faithful recreation of the original that features several practical enhancements, including a compact die-cast chassis and true-bypass switching.

If an item can not be repaired, a similar alternative product or cash discount (as defined in this policy) will be offeredGreen Signal: It is the output after the Tone Control, setat mid position. The signal is attenuated around 13dBs because at 1KHz the mid scoop is there and the shape is slightly changed. Fuzz pedals also don’t quite work as well with playing full chords, since the hard clipping makes all of the harmonic content of a full chord sound a little mushy and muddy. Generally, fuzz pedals work best with single chords or power chords, and usually, the tone of the pedal makes up for the simplicity of the notes you’re playing. Germanium vs Silicon vs Op-Amp? Circa 1978-1980 ( Pots typically date as early as 1978 and as late as 1981, though some have dates as early as 1976) GRAPHICS - Identical to the V4 Big muff, except “TONE BYPASS” was labeled on the top of these V5 units instead of "OFF ON". Input Capacitor C 1: creates a high-pass filter, increasing its value will result in a more bassy response and increasing the signal into the pedal. The cut-off frequency is around 3.8Hz, not disturbing guitar harmonics.