All Guitars & James Rogers

A single coil pickup is a type of magnetic transducer for the electric guitar and the electric bass. It electromagnetically converts the vibration of the strings to an electric signal. This article focuses on single coil only pickup designs, for more information about pickups in general, see pickup article.

Contents
1 History
1.1 Beauchamp
1.2 Gibson
2 Sound
3 Common designs
3.1 Gibson P-90
3.2 Telecaster design
3.3 Stratocaster design
4 Noise problems
5 Notable single-coil pickups
 

History
In the mid 1920s George Beauchamp, a Los Angeles, California guitarist, began experimentation with electric amplification of the guitar. Originally using a phonograph pickup assembly, Beauchamp began testing many different combinations of coils and magnets hoping to create the first electromagnetic guitar pickup. He wound his earliest coils using a motor out of a washing machine, later on switching to a sewing machine motor, and eventually using single coiled magnets.

Beauchamp was backed in his efforts by Adolph Rickenbacker, an engineer and wealthy owner of a successful tool and die business. Beauchamp eventually produced the first successful single coil pickup. The pickup consisted of two massive “U” shaped magnets and one coil and was known as the “horseshoe pickup”. The two horseshoe-shaped magnets surrounded the strings that passed over a single core plate (or blade) in the center of the coil.

Beauchamp outfitted the pickup in a custom built lap slide guitar. The production model based on this prototype became the Hawaiian Electro lap steel guitar, nicknamed the “Frying Pan” for its round, flat body.

In 1931 Beauchamp founded the Ro-Pat-In Company with Rickenbacker and his associates. Ro-Pat-In eventually became The Electro String Instrument Corporation and subsequently the Rickenbacker International Corporation. The company introduced its first “Electro-String Instruments” to the public in 1932.

Gibson
Main article: Charlie Christian pickup
The Gibson Guitar Corporation introduced the “bar pickup” in 1935 for its new line of Hawaiian lap steel guitars. The pickup’s basic construction is that of a metal blade inserted through the coil as a shared pole piece for all the strings. A pair of large flat magnets were fastened below the coil assembly.

In 1936 Gibson introduced the ES-150, its first electric Spanish styled guitar. The ES-150 was outfitted with the bar pickup. Jazz guitar innovator, Charlie Christian, began playing an ES-150 in the late 1930s with the Benny Goodman Orchestra. This caused the popularity of the electrified guitar to soar. Due to Christian’s close association with the ES-150 it began being referred to as the “Charlie Christian Model” and Gibson’s now famous bar pickup as the “Charlie Christian pickup” or “CC unit”.

Sound
The sound of a single coil pickup can range from the dark and fat midrange sound of the Gibson P-90 to the bright and clear Fender Telecaster single-coil tone.

Common designs
Gibson P-90
 
P-90s on Epiphone Casino, “dog-ear” variety.Main article: P-90
The P-90 is a single coil pickup designed by the Gibson Guitar Corporation. These pickups have a large flat coil with adjustable steel screws as pole pieces, and a pair of flat alnico bar magnets lying under the coil bobbin. The adjustable pole pieces pick up the magnetism from the magnets. Moving the screw closer or further away from the magnet determines signal strength, thus tone as well. There are 2 variations of P-90 pickup that differ mainly by mounting options:

Soap bar casing has true rectangular shape and the mounting screws are contained within the coil perimeter, positioned between the pole pieces, between strings 2-3 and 4-5, thus creating irregular and somewhat unusual pattern. Occasionally they are mistaken for pole pieces, thus sometimes P-90 is erroneously said to have 8 pole pieces. The “soap bar” nickname most probably comes from its predominantly rectangular shape and proportions resembling a bar of soap, and the fact that the first P-90s on the original Gibson Les Paul Model of 1952 were white.
Dog ear is a casing type with extensions at both sides of pickup that somewhat resemble dog’s ears. These are extensions of the predominantly rectangular cover that encompass the outlying mounting screws. Dog-ear P-90 pickups were commonly mounted on Gibson’s hollowbody guitars like the ES-330 and occasionally on solid body models like the Les Paul Junior. The same pickups were also available on Epiphone models (since Gibson was building Epiphone guitars in the 1950s) and the design is best remembered for its appearance on the hollow body Epiphone Casino of the mid to late 1960s.
The sound of a P-90 is somewhat brighter and more transparent than Gibson’s later humbucker pickup, and everybit as crisp and snappy as Fender’s single coil pickups despite its high output and big sound.

Despite its tonal qualities the P-90 fell out of favor with Gibson in the early 1950’s as a consequence of guitar players complaining about the amount of hum (noise) it put out. Gibson employee Seth Lover solved the hum problem by designing a hum-canceling pickup known as a humbucker, it was supposed to sound like a P-90 but in fact has quite a different sound. It nevertheless became Gibson’s mainstay pickup from that point on. The P-90 probably did not become as popular for that reason although its sound is widely considered to be more toneful.

The hum problem proved extremely difficult to solve and despite numerous attempts by Gibson with their P-100, and the larger aftermarket pickup manufacturers with their stacked and sidewinders noiseless designs, hum-canceling P-90 pickups lost most of their favored tonal characteristics and generally did not gain acceptance among guitar players.

In October 2009 Kinman Guitar Electrix, a boutique manufacturer specializing in the design and manufacture of hum-canceling pickups and run by inventor Chris Kinman, released a hum-canceling P-90 that has new ‘patent applied for’ technology that results in a 600 Ohm noise sensing coil. This new technology allows authentic P-90 sound with unchanged tonal qualities and has no noise hum.

Telecaster design
 
Two pickups on a TelecasterThe Fender Telecaster features two single-coils. The neck pickup produces a mellower sound, while the bridge pickup produces an extremely twangy, sharp tone with exaggerated treble response, because the bridge pickup is mounted on a steel plate. These design elements allow musicians to emulate steel guitar sounds, making it particularly appropriate for country music.

Pickups are selected with a 3-position switch, and two wiring schemes exist:

Vintage: 1) neck pickup with treble cutoff for a bassier sound; 2) neck pickup only; 3) bridge pickup only.
Modern: 1) neck pickup only, with no treble cutoff; 2) neck and bridge; 3) bridge pickup only.
The Fender Esquire has a variation to the Vintage wiring scheme by using the scheme on a single pickup. This gives a treble cutoff in the neck position, normal in the middle position, and a tone control cutoff in the bridge position.

Stratocaster design
 
Stratocaster pickups, viewed along the neck profile. Note that the poles are of different heights.The traditional Stratocaster design guitar features three single-coils. The guitarist can control which pickup or combination of pickups are selected with a lever switch. The pickup positions are usually referred to as the bridge, middle and neck pickups based on their proximity to those parts of the instrument.

Pickup position, number of coil winds, type of magnet wire, magnets and other factors shape the sound. A given pickup in the neck position will give louder, mellower and warmer sound, while an identical pickup in the bridge position will have lower output and produce a brighter, sharper sound. The reason the neck pickup has the most output is that the string’s vibration has a higher amplitude at the neck position, being near the middle of the string length. Some manufacturers overwind the bridge pickup for more output to compensate for this difference.

The magnet poles have different heights. This is called a magnet stagger and is done to compensate for the different outputs of the string for two reasons. The first reason is that the fretboard has a radius (also called camber) of between 7 and 12 inches usually. Naturally the strings will follow the radius of the fretboard and so must the top surface of the magnets, generally speaking. The second reason is that some strings have naturally higher output, the plain or non-wound G string being the most significant and this calls for the corresponding magnet to be further compensated, resulting in an apparent odd looking stagger. Fender Strat pickups generally follow the traditional design and have the G string’s magnet pole piece as tall as the D string’s, but this causes the G string of modern string sets to be excessively loud and dominate all the other strings. This comes about because Stratocaster pickups were designed in the 1950s when string sets came with a wound G string, but modern rock and blues players fount it difficult to stretch or bend wound G strings across the fretboard because of their inherently higher tension. In the 1970s, string manufacturers responded and introduced the now standard plain aka non-wound G string which has lower tension and can be stretched more easily, but which produces much higher output. In order for the G string to have the same output the corresponding magnet pole should have the greatest gap between the string and the magnet pole piece, thus different strings have magnets with differently compensated heights.

The first Stratocasters had a three-way pickup selector switch, selecting either the neck, middle or bridge pickup. Innovative guitarists found they could get an interesting sound by carefully positioning the selector switch lever between detented positions, where any two adjacent pickups would be on simultaneously. Some players wedged a plectrum between the pickguard and the selector switch to lock it in these positions. Later on, Fender introduced the now standard 5 way selector switch, which uses additional detents between the original three positions to allow the combinations of any two adjacent pickups.

Modern Stratocasters have 5 position pickup selector switch. Positions 1, 3 and 5 activate only one pickup (bridge, middle or neck respectively), while positions 2 and 4 activate a combination of two pickups (bridge and middle, or middle and neck, respectively). Some pickup sets have a reverse wound and reverse polarity middle pickup that when in combination with the normal bridge or neck pickups will cancel electromagnetic interference (noise/hum) which single coil pickups suffer badly from. The sonic effect of positions 2 and 4 is sometimes referred to as a “quack” or “notch positions”, and some guitar notation includes directions to use these pickup combinations. One example is “Sultans of Swing” by Dire Straits which is played in position 2 (bridge and middle).

Noise problems
Fender Stratocaster and Telecaster pickups, being of the single coil type, output a type of noise known and mains hum or 50Hz / 60Hz hum. Mains hum has its origin in wiring of a building and electrical apparatus/appliances such as transformers, electric motors and lighting. Hum is objectionable because it pollutes the musical notes being played on the instrument with its own sound of fixed unchanging frequency or pitch (usually 50 or 60 hertz) which is discordant with the musical sounds. To address this undesirable situation various attempts to eliminate mains hum signal from Fender single coil pickups were made dating back to the early 1970’s. DiMarzio, Seymour Duncan and EMG manufactured what are commonly known as stacked single coils which canceled mains hum. Unfortunately these stacks also canceled string signal and had a detrimental effect on sound quality. EMG used active circuitry within the pickup to compensate for the losses caused by stacked coils by boosting and reshaping the damaged sound but this required an on-board battery with its attendant problems. The resultant sound was not authentic Fender trade mark sound but EMG pickups became popular for their own sound.

Actodyne General manufactured a low noise design of single coil pickup known as Lace Sensors, Don Lace being the inventor. The Lace Sensor pickup had a rubberized particle magnet and used ferrous shielding to reduce hum. Being the best at the time Fender installed Lace Sensors on the Strat Plus model for many years as a solution to the mains hum problem. However the Lace Sensor was a stop gap solution because the sound was not authentic Fender trade mark sound. Fender purists wanted the genuine sound of the original Fender pickups with Alnico rod magnets and Fender eventually discontinued Lace Sensors as their mainstay solution to mains hum circa 1998. Lace Sensors continue to be be used by many guitar players regardless.

The search for an acceptable solution to mains hum gained new impetus circa 1995 when guitar players were increasingly intolerant of degraded stacked single coil sound. Fender were researching new techniques to solve the loss of tone around that time and eventually came out with their Vintage Noiseless design circa 1998. [1]

Notable single-coil pickups
There are several well-known single-coil pickups that have a distinctive sound:

Rickenbacker pickups (including the original 1930s “horseshoe” pickup as used in lap steel and solidbody upright basses, and later 6 string electric guitars, pedal steels, and electric bass guitars; also the “Toaster” and “Hi-Gain”)
Gibson bar pickup (1935) — later called the Charlie Christian pickup (1938)
Gibson P-90 (1946)
Fender Telecaster, Stratocaster, Jazzmaster, Jaguar, and other pickups
Danelectro Lipstick
Gretsch pickups (including the “HiLoTron”)
DeArmond pickups (found on various 50s and 60s guitars by various manufacturers including Gretsch, Guild, Epiphone, Martin, Kustom, Harmony, Regal, Premier, and others, but produced by the Rowe – DeArmond company of Toledo, Ohio; the trade name is now owned by Fender; single coil models including the 200 aka Dynasonic, 2K, and 2000, “mustache”, various “gold foil” types, and many clip on, rail, or screw mount pickups designed for acoustic guitars and other instruments). The Fender “Tele-Sonic” featured large DeArmond single coils.
Epiphone “New York” pickups
Lace Sensor pickups (1987)
Kinman Hx, patented noiseless passive relacement pickups for Fender and Gibson guitars by Kinman Guitar Electrix (1997)
Fender Vintage Noiseless pickups (1998)

There are a few basic set-up procedures that can take your guitar to the next level of quality tone for very little cost.  First place I start is the nut.  Most cheap guitars have plastic nuts. They just suck. You need a bone nut, well there are other options that have good tone and sustain but for argument sake I prefer bone and it’s better than plastic.  Some may argue there is little difference and maybe only be noticeable on open strings AND my answer to that is you obviously don’t have the ears to tell the difference.  No offense but I’ve earned the right guitar wise over the past 22+ years to voice my opinion. Everything you do to a guitar will affect the tone and removing a plastic nut and replacing it with a bone will make a night and day difference in your tone.

Tusq, Graphite etc are a few other types and I encourage others to comment on their preferences.  Really there are no right or wrong answers.  Maybe for some unknown reason there is someone who prefers a plastic nut!??

Haha. Maybe! Ya, never know.

ROGERS pickups are made for guitar players by an active professional guitar player and are named after myself (your blogger James Rogers). I hand build every pickup.  Within this blog you will find all you can about ROGERS pickups and more.  I will personally answer your questions should you have any at all.  To find more info about myself, my business and products check out the links section to the right of this page, or simply comment and I will answer the best that I can.

These pickups are built from the ground up with vulcanized fibre flatwork and Alnico 5 and Alnico 2 (when requested) magnets.  I magnetize the magnets in house and test each magnet with a hand held magnetometer to make sure each magnet has the correct gauss and can set the polarity to NORTH or SOUTH, whatever you require to calibrate your existing set or whatever you reasons are for a specific polarity. I can wind them clockwise or counter-clockwise.  I offer 2 types of wire, the highest quality wire available.  Poly-coated or plain enamel single build wire. All pickups are potted in wax to stop the possibility of microphonics.   Microphonics is that squealing or knocking sound you hear when you tap on a pickup.

I will pot your pickups for $10 + all shipping fees to and from my shop.  This makes it easier and safer for most people to just sent me their pickups.  I use wax, 80% paraffin and 20% bees wax.  This can be a VERY dangerous thing to do if you don’t know what your doing.  I will blog more about this another time.

At All Guitars I offer a SC (single-coil) tap.  As a guitarist who has toured the world playing blues with some of the best blues guitarists in the world I know the importance of tone.  I am not a gear head guitar pedal type of player.  I have always been known as the RAW traditional sounding blues guy.  Guitars are meant to sound a certain way and the more pedals you plug in the more you lose the ‘true’ sound and tone of the guitar.  I will write more on how to avoid pedals and use your guitar to get many different sounds without affecting tonal loss.  Now, back to the SC tap. Typically SC pickups have a ground wire and a hot wire using 2 eyelets.  A SC tap has a third eyelet. What does the third eyelet do is what your thinking right?  Well, I wind the ground lead and the first hot lead as normal to get a traditional typical (so-to-speak) sound, to a desired resistance basically.  THEN, I keep winding to get a second amount of resistance.

Example:  First lead wire has say 8000 windings and a 6kohm resistance, then wind another 1000 windings to 750ohm resistance. Hypothetically speaking, these numbers are off the top of my head and not specific or accurate.

In the photo below you will see a third eyelet. 

What this does is gives the guitar player more tonal options. Now you can use your standard 5-way switch and have the ability to tap in and out of the tap which will alter the tone.  A basic rule is that the more windings a pickup has the more resistance, more resistance means more output (louder) but it comes at a cost.  The more resistance a pickup has the less brightness it will have.  The lower the resistance the weaker the output and the brighter the pickup will sound.  Of course many other variables will change tonal qualities such as size of wire, type of magnets, etc.  So to have a variety of pickups or to understand what sound you want and customize a pickup to find that tone will have your guitar sounding like a 1 of a kind.  You don’t have to spend thousands on a guitar to have it sound good.  I have taken $100 cheap crap guitars and redone the electronics from capacitors to pickups and made them sound better than $10,000+ vintage strats.  At the end of the day, it is the guitarist.  A tech like myself can only do so much to help you get the best tonal qualities out of an instrument but if you can’t play, enough said!  Keep wood sheddin’ and get good!  

Hope you enjoyed this blog.  More to come. Cheers – James

When string tension is placed on an instruments neck, the neck will naturally want to bow forward with the tension, truss rods help us control and adjust neck bow.

To put it simply, when strings are plucked they vibrate in somewhat of an elliptical pattern and that is truly oversimplifying it. Because this pattern is wider near the center of the neck and tighter where the strings are anchored, relief (bow) gives the strings room to vibrate without contacting the frets and causing a buzz. Because necks, playing styles, pick attack, truss rods and strings gauges vary, the “ideal” neck relief can also vary from one instrument to another.
I have repaired many instruments that played beautifully with a relatively small amount of relief but there will always be circumstances (the player, the string gauge, the guitar)  that make a very flat neck inappropriate.
As with all set ups I must determine what the player desires and what the instrument is capable of and bring the two together to arrive at the ideal adjustment.

Tightening a truss rod forces the neck back and should reduce forward bow. 
Loosening a truss rod decreases resistance and compression to the back side of the neck allowing the strings tension to pull more relief (forward bow) into the neck.

Dual action truss rods These rods can add relief as well as straighten a neck. When turned counter clock wise the rod bends forward creating forward bow (relief) to the neck. These rods have small hex nuts that are welded to the end of the rod and unlike a tradition rod, the nut can not be removed.

Dual / Double truss rods Don’t confuse these with dual action (meaning a rod that can be bent both directions). Dual or double truss rods are most commonly found on 12 string or bass guitars for additional strength and rigidity. They are two individual truss rods laid side by side in the neck.

Non-adjustable truss rods/ neck reinforcement – To strengthen the neck and control bowing, necks are usually inlaid with “something”, be it a steel rod, graphite or other material for additional stiffness but not all necks have adjustable rods.
 
Two examples of non-adjustable truss rods on earlier Martin guitars.

Checking Relief

 Check your necks relief- Here is a simply way to check the relief in the neck if one doesn’t have a straightedge handy… the instrument strung to pitch fret a string on the 1st fret and where the neck meets the body.

Checking Relief

By fretting a string on 2 points we can then use the fretted string as a type of straightedge and get a visual as to how much relief is in the neck.

Measuring the gap between top of fret and bottom of string gives us an indication of how much relief is in the neck.

Now observe the space between the fretted string and the point of greatest relief…usually the 6th or 7th fret depending on the length of the neck. This gap can be measured with a feeler gauge if need be (you can place a capo on the first fret to free up one hand). If there is no gap, this is an indication that the neck is either dead flat or in a backward bow.
If the gap is substantial the truss rod may need to be tightened to reduce excess relief.

Determining the ideal relief  The ideal relief for your instruments neck will depend on string gauge, playing style and the instrument itself. (I’ve probably said that like 3 times now ah?) So you’re starting to get the idea that one size does not fit all and you can’t take some arbitrary measurements and make them work for all instruments. But you gotta start some where…are we in the ballpark or way over the fence.
Light pickers, jazz musicians and the like may find .004/.006 gives the neck a very fast feel. The necks stiffness and willingness to flex can sometimes interfere with our desires though.
Those who have a moderate to heavy strum, like flappy extra light gauge strings, have a rounder f/b radius etc. may come to realize more relief (say .008-.012) may be necessary so that the strings can avoid buzzing.

Once you understand how and when to adjust a truss rod you will be able to make incremental adjustments to arrive at your ideal relief and keep the necks relief finely tweaked. Some necks will require more frequent adjustments than others.
Changes in string gauges (tension) and humidity create the need to readjust the instruments truss rod throughout the instruments lifetime.

Adjusting The Truss Rod

Adjusting your truss rod Word of caution:  While I do not feel adjusting a truss rod is rocket science you should be aware that a broken truss rod is very bad news and normally…a very expensive repair. On inexpensive instruments broken truss rods are usually the kiss of death unless the rod can be removed without removal of the fingerboard. I am not trying to scare anyone, understanding how a rod works can save you from a catastrophe.

	If possible…first practice on a yard sale special. Tighten and loosen the nut and watch how it effects the necks relief. While I can certainly offer players some knowledge and understanding what I can’t give you is experience.
	You may wish to make a mark on the truss rod nut, when possible, so you can gauge your progress or return it to it’s previous position if necessary.
	Use the correct size Allen wrench or socket so you don’t damage the nut. Martin’s and many other acoustic guitars with truss rod nuts beneath the f/b extension use a 5mm allen head wrench. Gibson’s and others with a larger acorn style nut at the peghead use a 5/16″ nut socket. Taylor uses a smaller 1/4″ nut socket. Many Fender Electrics use a 1/8″ allen head wrench.
	Always start by loosening the nut first. If it is already as tight as it will go and you try to tighten it some more…pow! Adious truss rod, hello heartache.
	Make adjustments in small increments. A quarter of a turn would be allot of adjustment for most instruments. If your neck has a tremendous amount of relief in it and there is very little change after a good deal of tightening you’re  probably better off getting some advice.
	Adjustments to the truss rod are normally made with the instrument tuned to pitch. Without full tension on an instrument you can not judge your progress or effect. An exception would be Gotoh’s side adjuster. There are also instances where I will clamp the neck into a backbow before attempting to tightening the nut.
	If you encounter resistance, think twice about what you are about to do. It is so inexpensive to have a truss rod adjusted that it just doesn’t pay to take a big risk.
	Relief should be evaluated after each adjustment. Some necks take time to settle.
	Dry threads should be lubricated to prevent seizure.

Typical Truss Rod Wrenches

And another word of caution: I can not tell you how many people have been given the impression that the truss rod is some magic action lowering “key”, just turn it and the action gets lower.  Unaware of its true function they starting turning the rod until the strings get closer to the fingerboard, many times placing the neck into a backbow. If an instruments truss rod is properly adjusted and the action is high, adjustments to the nut and saddle are in order. Continuing to tighten a truss rod after the neck is dead flat serves no purpose as the instrument will simply buzz as the strings vibrate against the hump in the center of the board that has been created by backbowing the neck.

An Over-tightened truss rod – When a good deal of force is necessary to tighten a truss rod or if a neck fails to respond when the truss rod is tightened, its time to stop and ask for help. Greatly overtightening the rod can cause damage to the neck. I have seen some necks that were cracked at the truss rods anchor points (normally in the 1st to 3rd fret area). You should also bear in mind that excessive force may also merely be driving the truss rod nut into the wood (compressing it). When sensible measures have been taken without response it makes no sense to keep cranking away. Regardless of ones personal inability to stop and ask for directions…I would highly advise it at this juncture!

Truss Rod Adjustment Limitations and Problems

On most instruments adjusting the truss rod is a simple matter once you have an understanding of how it works, but inevitably there are going to be exceptions.
One such exception is when we have already arrived at a maximum adjustment and still have not removed (or added) enough relief. You may encounter a truss rod that is completely loose and the instruments still does not have enough relief or one that is as tight as possible and the neck still has way too much relief.
In both situations it is best to have it inspected to determine the best course of action.

When the neck is dead flat or in a backward bow I normally advise my clients to use a heavier gauge string in hopes that the additional tension may create the necessary relief. When heavier gauges will not do the trick it may be a candidate for a plane and refret. I can only determine the best course of action after inspecting it and undoubtedly, it is far easier for a luthier to straighten a neck with too much relief than it is to create relief in a neck that is bowing back.
Necks with far too much relief can sometimes be fixed by planeing and compression fretting. The use of fret wire with a larger tang causes a wedging effect and is sometimes enough to straighten or stiffen a neck.

Repairing a neck that is set in a backbowed position is a whole ‘nuther thing! I see this most often on 50’s-60’s Fender maple necks though they don’t have the corner on the market. The instrument will have to be inspected to determine whether planeing is an option and one should rarely expect necks in this condition to act perfectly normal.

Repairing Broken Truss Rods A stripped or broken truss rod is the kiss of death for most inexpensive instruments and the repair of such is usually only considered on instruments of value. In most cases, replacing a truss rod will require removal of the fingerboard.
The procedure can be quite time consuming on some instruments. The finish which is sprayed over the neck and fingerboard is chipped somewhat when separating the board from the neck. This can be a much bigger problem on necks with thick finishes or those with finishes that are more difficult to repair (i.e. U.V. cured finishes).
Because heat is required to soften the glue joint between the neck and board, celluloid inlays and binding can be damaged in the process, which will then require replacement. The heat may also cause the frets to spring free from their grasp.
Once the board has been removed I clamp it flat to reduce warpage or twist as it cools.
Depending on the instrument, some truss rods may be inlayed flush with the top of the neck, easily visible upon the boards removal or buried deeper and covered by a strip of wood.