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63-530: Larry DiMarzio began his career repairing guitars for professional musicians in Staten Island, New York, in the 1960s, often being asked to retrofit standard humbuckers into Les Paul Deluxes and Stratocasters . By the early '70s, DiMarzio felt alternatives were needed to the stock pickups being produced by major guitar manufacturers like Fender , Gibson , and Gretsch , all of which had been bought by large corporations that prioritized cutting costs at

126-401: A straight-line axis; for example, William Sturgeon 's electromagnet of 1824 consisted of a solenoid bent into a horseshoe shape (similarly to an arc spring ). Solenoids provide magnetic focusing of electrons in vacuums, notably in television camera tubes such as vidicons and image orthicons. Electrons take helical paths within the magnetic field. These solenoids, focus coils, surround nearly

189-492: A brighter ceramic magnet with smaller-gauge wire that allowed for more turns per coil, thereby significantly increasing its output. The pickup was designed to fit standard Gibson humbucker mounts to avoid installation problems and used open-coil, cream-colored bobbins, a style that was distinctive to DiMarzio pickups, and which the company later trademarked. The Super Distortion was quickly embraced by guitarists upon its release, with early adopters like Ace Frehley of Kiss —who

252-428: A constant hum or buzz. This is most noticeable when using distortion , fuzz, compressors , or other effects which, by adding gain to low-level signals, reduce the signal-to-noise ratio and therefore amplify the unwanted interference relative to the signal from the strings. Humbuckers work by pairing a coil that has the north poles of its magnets oriented "up" (toward the strings) with another coil alongside it with

315-450: A form factor that can be retrofit in place of a single coil. Many different kinds of "mini-humbuckers" are available from numerous manufacturers, and they produce a wide range of different tones. Not to be confused with the full size rail design. The origins of the hot rail/blade design are contested, with Joe Barden being quoted in Jan 1989 Guitar World magazine as claiming to having invented

378-471: A humbucker, and the patent USRE20070 describes the noise cancellation and current summation principles of such a design. This "Electric Translating Device" employed the solenoid windings of the pickup to magnetize the steel strings by means of switching on a short D.C. charge before switching over to amplification. In 1938, A.F. Knoblaugh invented a pickup for stringed instruments involving two stacked coils described in U.S. patent 2,119,584 . This pickup

441-496: A humbucking pattern beginning in late 1953 but dropped the design in 1954 due to the perceived distorted sound, which had stronger mid-range presence. The Gibson Les Paul was the first guitar to use humbuckers in large-scale production. Over the following decades, variants of practically every type of electric guitar have also been equipped with humbuckers, even types which are traditionally associated with single-coil pickups, like Fender Stratocasters and Telecasters . In particular,

504-444: A switch or within the pickup selector) so that only one coil is active. Slightly smaller than a traditional humbucker/double coil form factor. Many guitars feature cavities only for single-coil pickups. Installing full/double-sized humbuckers in this type of guitar requires additional routing of the woodwork, and/or cutting of the pickguard if the instrument has one. Many pickup manufacturers now produce humbucking pickup designs in

567-475: A uniform magnetic field in a volume of space when an electric current is passed through it. André-Marie Ampère coined the term solenoid in 1823, having conceived of the device in 1820. The French term originally created by Ampère is solénoïde , which is a French transliteration of the Greek word σωληνοειδὴς which means tubular . The helical coil of a solenoid does not necessarily need to revolve around

630-460: Is single coil . The "humbucking coil" was invented in 1934 by Electro-Voice , an American professional audio company based in South Bend, Indiana , that Al Kahn and Lou Burroughs incorporated in 1930 for the purpose of manufacturing portable public address equipment, including microphones and loudspeakers . The twin coiled guitar pickup invented by Arnold Lesti in 1935 is arranged as

693-443: Is a series/parallel switch, which in one position causes the coils to be connected in parallel rather than in series. This retains the humbucker's noise-cancellation properties, and gives a sound closer to that of two single-coil pickups used together. Coil splitting is often wrongly referred to as a "coil tapping". Coil taps are most commonly found on single coil pickups, and involve adding an extra hook-up wire during manufacture of

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756-424: Is also found in the balanced lines used in audio equipment. By convention, both humbucker coils are wound counterclockwise. The coils can be connected in series or in parallel in order to achieve this hum-cancellation effect, but humbucker pickups tend to be connected in series because that doubles the signal of the strings while keeping the hum reduced. Some types of humbucker pickups can be manually split (with

819-405: Is independent of current. Similar analysis applies to a solenoid with a magnetic core, but only if the length of the coil is much greater than the product of the relative permeability of the magnetic core and the diameter. That limits the simple analysis to low-permeability cores, or extremely long thin solenoids. The presence of a core can be taken into account in the above equations by replacing

882-425: Is just air (which behaves much like free space). In that scenario, the full effect of the high permeability material is not seen, but there will be an effective (or apparent) permeability μ eff such that 1 ≤  μ eff  ≤  μ r . The inclusion of a ferromagnetic core, such as iron , increases the magnitude of the magnetic flux density in the solenoid and raises the effective permeability of

945-429: Is magnetically isolated. The inverted signal of this coil only serves to cancel out the hum picked up by the other coil, with the actual string signal remaining unaffected. This is often used on bass guitars , where the type of pickup used has a greater effect on the instrument's overall sound, and the lower range of notes and their fundamental frequencies can match frequencies typically more heavily affected by hum. This

1008-591: Is no hum canceling effect. Usually, this feature is activated using a miniature toggle switch or a DPDT push-pull switch mounted on a potentiometer . Some guitars (e.g., the Peavey T-60 and the Fender Classic Player Jaguar HH) make use of a variable coil split circuit that allows the guitarist to dial a variable amount of signal from the second coil, from purely single coil to full humbucker and everything in-between. A similar option

1071-407: Is often called a "stacked" pickup, because the coils are most often "stacked" vertically, with the coil containing magnets placed closer to the strings. Another design known as the rail humbucker features a single magnetic component spanning across the entire string width of the instrument. These pickups are similar in size to single and double coil pickup, replacing the 6 slugs/magnets per coil. This

1134-408: Is often referred to as a "split coil" pickup, which should not be confused with the possibility of "coil-splitting" a regular humbucker, as discussed above. Both coils see nearly identical extraneous electromagnetic disturbances, and since they are wired in humbucking fashion, can effectively cancel them. However, the majority of the sound signal of any single note will mostly be generated by just one of

1197-404: Is sometimes expanded into a double sized "quadrail", or double humbucker, effectively combining 4 coils connected together to produce an extremely high-output pickup. The Kent Armstrong "Motherbucker" is an example of such an overpowered pickup. The same type of rails can also be found in a normal-size humbucker. Heavy metal guitarist Dimebag Darrell made heavy use of this type of pickup wired in

1260-476: Is the magnetic constant , N {\displaystyle N} the number of turns, I {\displaystyle I} the current and l {\displaystyle l} the length of the coil. Ignoring end effects, the total magnetic flux through the coil is obtained by multiplying the flux density B {\displaystyle B} by the cross-section area A {\displaystyle A} : Combining this with

1323-424: Is the magnetic flux density , l {\displaystyle l} is the length of the solenoid, μ 0 {\displaystyle \mu _{0}} is the magnetic constant , N {\displaystyle N} the number of turns, and I {\displaystyle I} the current. From this we get This equation is valid for a solenoid in free space, which means

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1386-482: The Fender Jazz Bass , introduced in 1960, which used a pair of single-coil pickups, one near the bridge and another about halfway between the bridge and the neck, and many Stratocaster style guitars, which often have 3 pickups with the middle one reversed electrically and magnetically. The usual five-way selector switch provides two humbucking settings, using the reversed middle pickup in parallel with either

1449-576: The Lace Sensor pickup, which uses proprietary screened bobbins to reduce hum while preserving single-coil tone. In the early 1980s DiMarzio introduced replacement pickups for Stratocaster and Telecaster guitars. These were of the stacked humbucker design, where the lower pickup coil functions solely to cancel hum. The DiMarzio "Super Distortion" pickup, introduced in 1972, was the first after-market replacement guitar pickup. With its much-increased output compared to humbuckers installed in guitars of

1512-401: The permeability of the magnetic path is the same as permeability of free space, μ 0 . If the solenoid is immersed in a material with relative permeability μ r , then the field is increased by that amount: In most solenoids, the solenoid is not immersed in a higher permeability material, but rather some portion of the space around the solenoid has the higher permeability material and some

1575-434: The right hand grip rule for the field around a wire. If we wrap our right hand around a wire with the thumb pointing in the direction of the current, the curl of the fingers shows how the field behaves. Since we are dealing with a long solenoid, all of the components of the magnetic field not pointing upwards cancel out by symmetry. Outside, a similar cancellation occurs, and the field is only pointing downwards. Now consider

1638-439: The south pole of its magnets oriented up. By connecting the coils together out of phase , the interference is significantly reduced via phase cancellation : the string signals from both coils add up instead of canceling because the magnets are placed in opposite polarity. This dramatically improves the signal-to-noise ratio . The technique has something in common with what electrical engineers call " common-mode rejection ", and

1701-1293: The vector potential , which for a finite solenoid with radius R and length l in cylindrical coordinates ( ρ , ϕ , z ) {\displaystyle (\rho ,\phi ,z)} is A ϕ = μ 0 I π R l [ ζ ( R + ρ ) 2 + ζ 2 ( m + n − m n m n K ( m ) − 1 m E ( m ) + n − 1 n Π ( n , m ) ) ] ζ − ζ + , {\displaystyle A_{\phi }={\frac {\mu _{0}I}{\pi }}{\frac {R}{l}}\left[{\frac {\zeta }{\sqrt {(R+\rho )^{2}+\zeta ^{2}}}}\left({\frac {m+n-mn}{mn}}K(m)-{\frac {1}{m}}E(m)+{\frac {n-1}{n}}\Pi (n,m)\right)\right]_{\zeta _{-}}^{\zeta _{+}},} Where: Here, K ( m ) {\displaystyle K(m)} , E ( m ) {\displaystyle E(m)} , and Π ( n , m ) {\displaystyle \Pi (n,m)} are complete elliptic integrals of

1764-556: The " Superstrat " style of guitar. In any magnetic pickup, a vibrating guitar string, magnetized by a fixed magnet within the pickup, induces an alternating voltage across its coil. However, wire coils also make excellent antennas and are therefore sensitive to electromagnetic interference caused by alternating magnetic fields from mains wiring ( mains hum ) and electrical appliances like transformers, motors, and computer screens , especially older CRT monitors. Guitar pickups reproduce this noise, which can be quite audible, sounding like

1827-403: The bridge or neck pickup. If the pickups are wired in series instead of parallel, the resulting sound is close to that of a normal humbucker. It is even closer to a humbucker-type sound if the coils are placed closer together. In 1957, Fender introduced a split pickup to its Precision Bass , where one coil is serving the E and A strings, and the other one the D and G strings. This configuration

1890-423: The bridge position. These tend to have a higher output and bass response than the single coil-sized versions. DiMarzio has designed and sold many such pickups. Some guitars which have humbucking pickups feature "coil splits", which allow the pickups to act as "pseudo-single" coils by either short-circuiting or bypassing one coil. The electrical circuit of the pickup is reduced to that of a true single coil so there

1953-437: The coils, so that output level and tonal qualities are much closer to a regular single-coil pickup. The resulting "P-Style" pickup is usually regarded as the main ingredient of the "P-Bass" sound, and many variants on the design are offered by many manufacturers. The concept was later developed into G&L 's "Z-coil" pickup, which is used for standard guitars such as their Comanche model. In 1985, Lace Music Products introduced

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2016-400: The definition of inductance the inductance of a solenoid follows as A table of inductance for short solenoids of various diameter to length ratios has been calculated by Dellinger, Whittmore, and Ould. This, and the inductance of more complicated shapes, can be derived from Maxwell's equations . For rigid air-core coils, inductance is a function of coil geometry and number of turns, and

2079-475: The design in late 1983. The US patent for the L-500 attributes the hot rail design to Bill Lawrence. Two flat vertical magnetically conductive blades are placed side by side within half the width of a typical fender strat/telecaster sized single coil. Both "blades/rails" pass under all strings and placed lengthwise, each with its own winding around one rail/blade, and a magnet placed directly under and contacting

2142-405: The distance from the axis nor on the solenoid's cross-sectional area. This is a derivation of the magnetic flux density around a solenoid that is long enough so that fringe effects can be ignored. In Figure 1, we immediately know that the flux density vector points in the positive z direction inside the solenoid, and in the negative z direction outside the solenoid. We confirm this by applying

2205-482: The expense of product quality. His first offering was the "FS-1," a pickup designed to reduce the often shrill nature of stock Stratocaster bridge pickups, and which found an early fan in Pink Floyd 's David Gilmour . Knowing many rock guitarists sought a way to create more distorted tones at lower volumes and without relying on fuzz pedals , DiMarzio released the "Super Distortion" humbucker in 1972. It combined

2268-405: The field is pointing upwards inside the solenoid, so the horizontal portions of loop c do not contribute anything to the integral. Thus the integral of the up side 1 is equal to the integral of the down side 2. Since we can arbitrarily change the dimensions of the loop and get the same result, the only physical explanation is that the integrands are actually equal, that is, the magnetic field inside

2331-416: The field outside must go to zero as the solenoid gets longer. Of course, if the solenoid is constructed as a wire spiral (as often done in practice), then it emanates an outside field the same way as a single wire, due to the current flowing overall down the length of the solenoid. Applying Ampère's circuital law to the solenoid (see figure on the right) gives us where B {\displaystyle B}

2394-1577: The first, second, and third kind. Using: B → = ∇ × A → , {\displaystyle {\vec {B}}=\nabla \times {\vec {A}},} The magnetic flux density is obtained as B ρ = μ 0 I 4 π 1 l ρ [ ( R + ρ ) 2 + ζ 2 ( ( m − 2 ) K ( m ) + 2 E ( m ) ) ] ζ − ζ + , {\displaystyle B_{\rho }={\frac {\mu _{0}I}{4\pi }}{\frac {1}{l\,\rho }}\left[{\sqrt {(R+\rho )^{2}+\zeta ^{2}}}{\biggl (}(m-2)K(m)+2E(m){\biggr )}\right]_{\zeta _{-}}^{\zeta _{+}},} B z = μ 0 I 2 π 1 l [ ζ ( R + ρ ) 2 + ζ 2 ( K ( m ) + R − ρ R + ρ Π ( n , m ) ) ] ζ − ζ + . {\displaystyle B_{z}={\frac {\mu _{0}I}{2\pi }}{\frac {1}{l}}\left[{\frac {\zeta }{\sqrt {(R+\rho )^{2}+\zeta ^{2}}}}\left(K(m)+{\frac {R-\rho }{R+\rho }}\Pi (n,m)\right)\right]_{\zeta _{-}}^{\zeta _{+}}.} On

2457-412: The flux density outside is practically zero since the radii of the field outside the solenoid will tend to infinity. An intuitive argument can also be used to show that the flux density outside the solenoid is actually zero. Magnetic field lines only exist as loops, they cannot diverge from or converge to a point like electric field lines can (see Gauss's law for magnetism ). The magnetic field lines follow

2520-430: The imaginary loop c that is located inside the solenoid. By Ampère's law , we know that the line integral of B (the magnetic flux density vector) around this loop is zero, since it encloses no electrical currents (it can be also assumed that the circuital electric field passing through the loop is constant under such conditions: a constant or constantly changing current through the solenoid). We have shown above that

2583-433: The intrinsic inductance and capacitance cannot be done using those for the conventional solenoids, i.e. the tightly wound ones. New calculation methods were proposed for the calculation of intrinsic inductance (codes available at ) and capacitance. (codes available at ) As shown above, the magnetic flux density B {\displaystyle B} within the coil is practically constant and given by where μ 0

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2646-402: The longitudinal path of the solenoid inside, so they must go in the opposite direction outside of the solenoid so that the lines can form loops. However, the volume outside the solenoid is much greater than the volume inside, so the density of magnetic field lines outside is greatly reduced. Now recall that the field outside is constant. In order for the total number of field lines to be conserved,

2709-782: The magnetic flux density through the centre of the solenoid (in the z direction, parallel to the solenoid's length, where the coil is centered at z =0) can be estimated as the flux density of a single circular conductor loop: Within the category of finite solenoids, there are those that are sparsely wound with a single pitch, those that are sparsely wound with varying pitches (varied-pitch solenoid), and those with varying radii for different loops (non-cylindrical solenoids). They are called irregular solenoids . They have found applications in different areas, such as sparsely wound solenoids for wireless power transfer , varied-pitch solenoids for magnetic resonance imaging (MRI), and non-cylindrical solenoids for other medical devices. The calculation of

2772-465: The magnetic path. This is expressed by the formula where μ eff is the effective or apparent permeability of the core. The effective permeability is a function of the geometric properties of the core and its relative permeability. The terms relative permeability (a property of just the material) and effective permeability (a property of the whole structure) are often confused; they can differ by many orders of magnitude. For an open magnetic structure,

2835-420: The opposite ends of the core, rather than the now more common top-bottom orientation. To overcome the hum problem for guitars, a humbucking pickup was invented by Seth Lover of Gibson under instruction of then-president Ted McCarty. About the same time, Ray Butts developed a similar pickup that was taken up by Gretsch guitars. Although Gibson's patent was filed almost two years before Gretsch's, their patent

2898-416: The original humbucker remains the most common noise-reducing pickup design, inventors have tried many other approaches to reducing noise in guitar pickups. Many instruments combine separate single-coil pickups in a hum reducing configuration by reversing the electrical phase of one of the pickups. This arrangement is similar to that of a humbucking pickup and effectively reduces noise. Examples of this include

2961-446: The pickup so the guitarist can choose to have all the windings of the pickup included in the circuit, for a fatter, higher output sound with more midrange, or switch the output to 'Tap' into the windings at a point less than the full coil for a brighter, lower-output and cleaner sound. For example: a full pickup coil may be 10,000 turns of wire and the "Tap" may be at 8000 turns. Because of the confusion between coil splits and coil taps—and

3024-452: The public imagination between the [trade]marks at issue and DiMarzio." Lawrence P. DiMarzio holds following US patents: Humbuckers A humbucker , humbucking pickup , or double coil , is a guitar pickup that uses two wire coils to cancel out noisy interference from coil pickups . Humbucking coils are also used in dynamic microphones to cancel electromagnetic hum. Humbuckers are one of two main types of guitar pickups. The other

3087-474: The rareness of coil taps in general—it is difficult to find tappable single-coil pickups for sale. However, pickup manufacturer Seymour Duncan offers tapped versions of many of their Telecaster and Stratocaster pickups. The split single coil may bear little resemblance to popular single coil pickups such as those made by Fender and the P-90 made by Gibson, owing to other differences in pickup construction. While

3150-676: The relationship between the effective permeability and relative permeability is given as follows: where k is the demagnetization factor of the core. A finite solenoid is a solenoid with finite length. Continuous means that the solenoid is not formed by discrete coils but by a sheet of conductive material. We assume the current is uniformly distributed on the surface of the solenoid, with a surface current density K ; in cylindrical coordinates : K → = I l ϕ ^ . {\displaystyle {\vec {K}}={\frac {I}{l}}{\hat {\phi }}.} The magnetic field can be found using

3213-408: The replacement of the bridge pickup in a Stratocaster-type guitar with a humbucker, resulting in a pickup configuration noted as H-S-S (starting at bridge pickup: H for humbucker, S for single coil) has gained much popularity. Guitars in this configuration are sometimes referred to as "Fat Strats", because of the "fatter", "rounder" tone offered by the humbucking pickup, and are also closely related to

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3276-432: The same form factor as a traditional single coil style. Though cancelling hum while preserving the original single coil appearance, stacked designs can sacrifice some of the "bite" in higher frequencies partially due to capacitative effect of closely/machine wound coils as well as other tonal differences resulting from the second coil having the magnet through it also. In some designs one of the coils simply has no magnet, or

3339-420: The solenoid is radially uniform. Note, though, that nothing prohibits it from varying longitudinally, which in fact, it does. A similar argument can be applied to the loop a to conclude that the field outside the solenoid is radially uniform or constant. This last result, which holds strictly true only near the center of the solenoid where the field lines are parallel to its length, is important as it shows that

3402-471: The solenoid, far away from the ends ( l / 2 − | z | ≫ R {\displaystyle l/2-|z|\gg R} ), this tends towards the constant value B = μ 0 N I / l {\displaystyle B=\mu _{0}NI/l} . For the case in which the radius is much larger than the length of the solenoid ( R ≫ l {\displaystyle R\gg l} ),

3465-656: The symmetry axis, the radial component vanishes, and the axial field component is B z = μ 0 N I 2 ( z + l / 2 l R 2 + ( z + l / 2 ) 2 − z − l / 2 l R 2 + ( z − l / 2 ) 2 ) . {\displaystyle B_{z}={\frac {\mu _{0}NI}{2}}\left({\frac {z+l/2}{l{\sqrt {R^{2}+(z+l/2)^{2}}}}}-{\frac {z-l/2}{l{\sqrt {R^{2}+(z-l/2)^{2}}}}}\right).} Inside

3528-401: The time, it became an instant favourite of many hard-rock guitarists, and it remains a popular choice for a pickup upgrade decades later. Solenoid A solenoid ( / ˈ s oʊ l ə n ɔɪ d / ) is a type of electromagnet formed by a helical coil of wire whose length is substantially greater than its diameter, which generates a controlled magnetic field . The coil can produce

3591-447: The two blades. Similar to full/double size hum bucking designs, one coil is reverse wound to cancel hum. Fender came out with their Fender Noiseless Pickups , a stacked bobbin design, around 1998. Fender's Noiseless pickups utilize two separate coils one on top of another, wound with one coil reverse wound to cancel hum, around a common set of magnetic pole pieces commonly referred to as the "bobbin". These "stacked" humbuckers were in

3654-443: The whole length of the tube. An infinite solenoid has infinite length but finite diameter. "Continuous" means that the solenoid is not formed by discrete finite-width coils but by many infinitely thin coils with no space between them; in this abstraction, the solenoid is often viewed as a cylindrical sheet of conductive material. The magnetic field inside an infinitely long solenoid is homogeneous and its strength neither depends on

3717-401: Was first to use the double-cream bobbin design and that DiMarzio never had a right to the term "PAF," as it had no related patents, and that widespread use of "PAF" had rendered it generic and un-trademarkable. DiMarzio has opposed Gibson's claims, arguing Gibson is time-barred from challenging DiMarzio's trademarks and that Gibson had failed to make any allegations "related to the association in

3780-479: Was granted the trademark for " PAF " in 1978, with the company claiming to have been the first to use the term in commerce in 1976, in reference to their pickups recreating the original Gibson PAF sound. DiMarzio argued this marketing use was legally distinct from Gibson's use of the original "patent applied for" stickers. DiMarzio was also granted the trademark for its double-cream bobbin humbucker design. In 2023, Gibson filed to cancel these trademarks, arguing Gibson

3843-692: Was introduced to DiMarzio by DiMarzio's college classmate Gene Simmons —and Joe Perry of Aerosmith . In the '80s, the pickup was used by many metal and hard rock players, including Dimebag Darrell , Kerry King , and Randy Rhoads , while Kurt Cobain and Kim Thayil adopted it in the '90s. Emerging guitar companies like B.C. Rich , Charvel , and Hamer used the Super Distortion in their early guitars. As of 2016, DiMarzio offered nearly 200 pickup models, including traditional passive single coils and humbuckers, battery-powered active pickups, and models for seven- and eight-string guitars. DiMarzio

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3906-627: Was issued four weeks after Gretsch's. Both patents describe a reverse-wound and reverse-polarity pair of coils. A successful early humbucking pickup was the type which is nowadays known as the " PAF " (literally "Patent Applied For") invented by Seth Lover in 1955. Because of this, and because of its use on the Gibson Les Paul guitar, popularization of the humbucker is strongly associated with Gibson, although humbuckers had been used in many different guitar designs by other manufacturers before. Rickenbacker offered dual coil pickups arranged in

3969-480: Was to be used in pianos, since he was working for Baldwin Piano at the time. The 1939 April edition of Radio Craft Magazine shows how to construct a guitar pickup made with two identical coils wrapped around self-magnetized iron cores, where one is then flipped over to create a reverse-wound, reverse-polarity, humbucking orientation. The iron cores of these pickups were magnetized to have their north–south poles at

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