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39-493: Arbiter Electronics Ltd. first issued the Fuzz Face in 1966. Later units bear the "Dallas Arbiter", "Dallas Music Industries Ltd.", "CBS/Arbiter Ltd." or "Dunlop Manufacturing Inc." name. The earliest units used germanium transistors . Silicon transistors were used in later editions of the pedal. Silicon transistors provided for a more stable operation, but have a different, harsher sound. The electronics are contained in

78-432: A signal from one circuit to another while transforming its electrical impedance to provide a more ideal source (with a lower output impedance for a voltage buffer or a higher output impedance for a current buffer ). This "buffers" the signal source in the first circuit against being affected by currents from the electrical load of the second circuit and may simply be called a buffer or follower when context

117-411: A source follower because the source voltage follows the gate voltage or, again, a voltage follower because the output voltage follows the input voltage); or similar configurations using vacuum tubes ( cathode follower ), or other active devices. All such amplifiers actually have a gain of slightly less than unity (though the loss may be small and unimportant) and add a DC offset . Only one transistor

156-414: A circular-shaped metal housing. Ivor Arbiter "got the idea for the round shape when he one day saw a microphone stand with a cast iron base". The design was originally intended to be used as a microphone base for guitarists who sang. The pedal uses two knobs, one for volume, and one for the amount of distortion the pedal produces. The arrangement of controls and logo on the box suggests a face. The circuit

195-574: A gain of 1 (or the equivalent 0  dB ), referring to the voltage gain. As an example, consider a Thévenin source (voltage V A , series resistance R A ) driving a resistor load R L . Because of voltage division (also referred to as "loading") the voltage across the load is only ⁠ V A R L / R L + R A ⁠ . However, if the Thévenin source drives a unity gain buffer such as that in Figure 1 (top, with unity gain),

234-552: A large manufacturer of music gear. Dunlop has acquired several well-known effects pedal brands, including Cry Baby , MXR and Way Huge. Scottish immigrant Jim Dunlop founded the Jim Dunlop Company in 1965 as a part-time business while working as a processing and chemical engineer at Barr and Stroud in Glasgow. He was an apprentice of the creator of the first hip replacement, William "Bill" Wallace. His first product

273-646: A low input impedance and thus is very sensitive to the guitar pickup. By rolling the volume knob, the guitar player can decrease the gain of the pedal and get a clean or crunch sound, while still having all the gain when the volume knob is on maximum. For the same reason, Fuzz Face pedals react differently when placed directly after the guitar than when after other pedals or after a buffer amplifier . While some claim Wah-wah pedals are known to be troublesome with Fuzz Faces, artists such as Hendrix were known to use them together to spectacular effect. His signal flow for live performance involved first plugging his guitar into

312-475: A variety of Fuzz Face units until this day. Several germanium and silicon models are available. In 2013, smaller versions with status LEDs and AC power jacks were introduced. In the late 1990s, Arbiter reissued the pedal. The circuit uses only a small number of components, plus a battery. Its sound is mostly dependent on the selection of transistors (type, h fe and leakage in case of germanium transistors). As germanium transistors are sensitive to temperature,

351-518: A variety of electronic effects, including the original Cry Baby wah-wah pedal, the Uni-Vibe phaser , Heil Talk Box , and the MXR and Way Huge lines of stompboxes . Dunlop Manufacturing founder Jim Dunlop Sr died on February 6, 2019, at the age of 82. Jeorge Tripps launched Way Huge in 1992. In late 1999 the company closed its doors when Tripps went to work for Line 6 . In 2008, Tripps and

390-464: A wah-wah pedal, then connecting the wah-wah pedal to a Fuzz Face, which was then linked to a Uni-Vibe , before connecting to a Marshall amplifier. Dunlop Manufacturing Dunlop Manufacturing, Inc. is a manufacturer of musical accessories, especially effects units , based in Benicia, California , United States. Founded in 1965 by Jim Dunlop Sr., the company grew from a small home operation to

429-459: Is 1), the amplifier is again a unity gain buffer ; this time known as a current follower because the output current follows or tracks the input current. As an example, consider a Norton source (current I A , parallel resistance R A ) driving a resistor load R L . Because of current division (also referred to as "loading") the current delivered to the load is only ⁠ I A R A / R L + R A ⁠ . However, if

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468-424: Is an ideal voltage source V A with zero Thévenin resistance. Typically a current buffer amplifier is used to transform a current signal with a low output impedance from a first circuit into an identical current with high impedance for a second circuit. The interposed buffer amplifier prevents the second circuit from loading the first circuit's current unacceptably and interfering with its desired operation. In

507-410: Is applied to the emitter node of the transistor by an AC Norton current source with Norton resistance R S . The AC output current i out is delivered by the buffer via a large coupling capacitor to load R L . This coupling capacitor is large enough to be a short circuit at frequencies of interest. Because the transistor output resistance connects input and output sides of the circuit, there

546-525: Is based on the shunt-series-feedback amplifier topology - a standard in engineering textbooks. Sola Sound and Vox had been using the same circuit topology for their Tone Bender pedals earlier in 1966. The Fuzz Face is particularly similar to the Sola Sound unit known today as the "Mk1.5" Tone Bender. The main difference is that the Fuzz Face is biased slightly colder, making it more usable in warm environments. The original instructions even described

585-409: Is clear. A voltage buffer amplifier is used to transform a voltage signal with high output impedance from a first circuit into an identical voltage with low impedance for a second circuit. The interposed buffer amplifier prevents the second circuit from loading the first circuit unacceptably and interfering with its desired operation, since without the voltage buffer, the voltage of the second circuit

624-537: Is expected. In this configuration, the entire output voltage (β = 1 in Fig. 2) is fed back into the inverting input. The difference between the non-inverting input voltage and the inverting input voltage is amplified by the op-amp. This connection forces the op-amp to adjust its output voltage to simply equal the input voltage (V out follows V in so the circuit is named op-amp voltage follower). The impedance of this circuit does not come from any change in voltage, but from

663-403: Is influenced by output impedance of the first circuit (as it is larger than the input impedance of the second circuit). In the ideal voltage buffer (Figure 1 top), the input impedance is infinite and the output impedance is zero. Other properties of the ideal buffer are: perfect linearity, regardless of signal amplitudes; and instant output response, regardless of the speed of the input signal. If

702-402: Is shown as the active device in these schematics (however, the current source these circuits may require transistors too). Using the small-signal circuit in Figure 4, the impedance seen looking into the circuit is (The analysis uses the relation g m r π = (I C /V T ) (V T /I B ) = β, which follows from the evaluation of these parameters in terms of the bias currents.) Assuming

741-420: The 'Penny Saver Royale' and the 'Overrated Special'. Introduced in 1981, Tortex is the company's brand name for an acetal based line of plectra . The overall feeling of the picks is meant to mimic the feeling of vintage tortoise shell picks (as genuine tortoise shell picks have been banned since 1973). Buffer amplifier In electronics , a buffer amplifier is a unity gain amplifier that copies

780-572: The Fuzz Face as a "Tone-Bending" unit. Dallas Music Industries made a final batch of Fuzz Face units in 1976 or 1977, shortly after moving to the United States. The company bought Crest Audio in the 1980s and although it was operating under that name when it reissued the Fuzz Face in 1986, the units still bore the Dallas-Arbiter name. They made about 2000 Fuzz Faces until 1990. In 1993 Dunlop Manufacturing took over production, making

819-489: The Norton source drives a unity gain buffer such as that in Figure 1 (bottom, with unity gain), the current input to the amplifier is I A , with no current division because the amplifier input resistance is zero. At the output the dependent current source delivers current β i I A = I A to the load, again without current division because the output resistance of the buffer is infinite. A Norton equivalent circuit of

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858-406: The amount of leakage is variable. Thus the bias voltages will shift up and down, so the sound produced by a germanium Fuzz Face may change as the equipment heats up or cools down. Also, the battery is part of the circuit. Variances in voltage and internal resistance can make an audible difference. According to Jimi Hendrix ’s guitar tech Roger Mayer , Jimi would buy half a dozen Fuzz Faces and mark

897-463: The combined original Norton source and the buffer is an ideal current source I A with infinite Norton resistance. A unity gain buffer amplifier may be constructed by applying a full series negative feedback (Fig. 2) to an op-amp simply by connecting its output to its inverting input, and connecting the signal source to the non-inverting input (Fig. 3). Unity gain here implies a voltage gain of one (i.e. 0 dB), but significant current gain

936-650: The company moved to Dunlop Manufacturing and resurrected the Way Huge line, including the Swollen Pickle (a fuzz), Pork Loin (an overdrive), Fat Sandwich (a distortion), and Green Rhino (another overdrive). They have also recently reissued the much sought-after and often cloned Red Llama overdrive, notable for its volume boost and gain past 2 o'clock which results in a sound that is very distorted and has considerable mid-range presence. Way Huge has also collaborated with Joe Bonamassa on various drive pedals including

975-419: The ideal current buffer (Figure 1 bottom), the output impedance is infinite (an ideal current source) and the input impedance is zero (a short circuit). Again, other properties of the ideal buffer are: perfect linearity, regardless of signal amplitudes; and instant output response, regardless of the speed of the input signal. For a current buffer, if the current is transferred unchanged (the current gain β i

1014-452: The impedance seen looking into the circuit is no longer R L but instead is infinite (at low frequencies) because the MOSFET draws no current. As frequency is increased, the parasitic capacitances of the transistors come into play and the transformed input impedance drops with frequency. Some configurations of single-transistor amplifier can be used as a buffer to isolate the driver from

1053-457: The input and output impedances of the op-amp. The input impedance of the op-amp is very high (1 MΩ to 10 TΩ ), meaning that the input of the op-amp does not load down the source and draws only minimal current from it. Because the output impedance of the op-amp is very low, it drives the load as if it were a perfect voltage source . Both the connections to and from the buffer are therefore bridging connections, which reduce power consumption in

1092-400: The load. For most digital applications, an NMOS voltage follower (common drain) is the preferred configuration. These amplifiers have high input impedance, which means that the digital system will not need to supply a large current. A non-linear buffer amplifier is sometimes used in digital circuits where a high current is required, perhaps for driving more gates than the normal fan-out of

1131-695: The logic family used, or for driving displays, or long wires, or other difficult loads. It is common for a single package to contain several discrete buffer amplifiers. For example, a hex buffer is a single package containing 6 buffer amplifiers, and an octal buffer is a single package containing 8 buffer amplifiers. The terms inverting buffer and non-inverting buffer effectively correspond with high-current capability single-input NOR or OR gates respectively. The majority of amplifiers used to drive large speaker arrays, such as those used for rock concerts, are amplifiers with 26-36dB voltage gain capable of high amounts of current into low impedance speaker arrays where

1170-603: The one he liked best only to find out that he didn't like it in a different environment. Despite popular belief that Arbiter used randomly selected pairs of transistors, Dennis Cornell, one of the engineers who worked for Arbiter in the 1960s, described in a 2016 Guitarist magazine article how he auditioned them for their sonic properties. Early units used AC128 or NKT275 germanium transistors. Later on, BC183L, BC183KA, BC130C, BC108C, BC209C and BC239C silicon transistors were used. The American made versions used BC109C transistors. Arbiter reissues used AC128s. Hendrix also switched to

1209-637: The signal line. Simple unity gain buffer amplifiers include the bipolar junction transistor in common-base configuration, or the MOSFET in common-gate configuration (called a current follower because the output current follows the input current). The current gain of a current buffer amplifier is (approximately) unity. Figure 6 shows a bipolar current buffer biased with a current source (designated I E for DC emitter current) and driving another DC current source as active load (designated I C for DC collector current). The AC input signal current i in

Fuzz Face - Misplaced Pages Continue

1248-552: The silicon transistors, but they created additional difficulties on stage, since they are much more susceptible to receiving AM radio signals, which were then audible through the guitar amplifier. The Fuzz Face's continuing popularity and status as a classic may be explained by its many famous users, which include Jimi Hendrix , David Gilmour , Duane Allman , Stevie Ray Vaughan Pete Townshend , Eric Johnson , George Harrison . and Kevin Parker The Fuzz Face has

1287-444: The source, distortion from overloading, crosstalk and other electromagnetic interference . Other unity gain buffer amplifiers include the bipolar junction transistor in common-collector configuration (called an emitter follower because the emitter voltage follows the base voltage, or a voltage follower because the output voltage follows the input voltage); the field effect transistor in common-drain configuration (called

1326-424: The speakers are wired in parallel. A driven guard utilizes a voltage buffer to protect a very high impedance signal line by surrounding the line with a shield driven by a buffer to the same voltage as the line, the close voltage matching of the buffer prevents the shield from leaking significant current into the high impedance line while the low impedance of the shield can absorb any stray currents that could affect

1365-993: The toggle capo, and then worked with a local machine shop to build the first capo dies , manufacturing what eventually became the long running "1100 series" capo. Starting from his living room, Dunlop later moved construction to his garage, and then to a location outside the house. On March 19, 1972, he moved into the pick market, after reading every issue of Guitar Player magazine and noting musicians’ comments concerning what they liked and did not like about picks. He made his first picks from nylon , and continues to produce these. Also in 1972, Dunlop left his job at Dymo Industries to focus on his own company full-time. He moved his family to Benicia, California and set up shop in Benicia Industrial Park. A few years later, he outgrew that building and moved to Industrial Way. Dunlop products now range from capos and picks to slides , strings , fret wire, strap retainers, and

1404-401: The usual case where r O >> R L , the impedance looking into the buffer is larger than the load R L without the buffer by a factor of (β + 1), which is substantial because β is large. The impedance is increased even more by the added r π , but often r π << (β + 1) R L , so the addition does not make much difference Using the small-signal circuit in Figure 5,

1443-400: The voltage input to the amplifier is V A , and with no voltage division because the amplifier input resistance is infinite. At the output the dependent voltage source delivers voltage A v V A = V A to the load, again without voltage division because the output resistance of the buffer is zero. A Thévenin equivalent circuit of the combined original Thévenin source and the buffer

1482-412: The voltage is transferred unchanged (the voltage gain A v is 1), the amplifier is a unity gain buffer ; also known as a voltage follower because the output voltage follows or tracks the input voltage. Although the voltage gain of a voltage buffer amplifier may be (approximately) unity, it usually provides considerable current gain and thus power gain. However, it is commonplace to say that it has

1521-486: Was the Vibra-Tuner, a small device that attached to a guitar with a suction cup and displayed whether the guitar was in tune with the vibration of a small reed. While visiting music stores to sell his new product, someone told him that musicians needed a good capo , remarking that anyone who made a good capo that could handle a 12-string guitar would make a lot of money. Using his engineering background, Dunlop created

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