An electric guitar is a type of guitar that needs an amplifier to be heard clearly during performances, unlike an acoustic guitar, which produces sound on its own. It uses pickups to change the vibrations of its strings into electrical signals. These signals are then played through loudspeakers to create sound. The sound can be changed using amplifier settings or effects like reverb, distortion, and overdrive. Overdrive is especially important in styles like electric blues, jazz, rock, and heavy metal. Some guitars combine features of electric and acoustic guitars, such as semi-acoustic and acoustic-electric models.
The electric guitar was invented in 1932 and was first used by jazz musicians who wanted to play clear, single-note solos in large ensembles. Early musicians who recorded with electric guitars include Les Paul, Eddie Durham, George Barnes, Lonnie Johnson, Sister Rosetta Tharpe, T-Bone Walker, and Charlie Christian. During the 1950s and 1960s, the electric guitar became the most important instrument in popular music. It can create many different sounds and is used in genres like pop, rock, folk, country, blues, and jazz. It also helped shape the development of electric blues, rock and roll, rock music, and heavy metal.
Electric guitars come in many designs. The body and neck shapes vary, as do the bridges and pickups. Some guitars have a fixed bridge, while others have a spring-loaded bridge that allows players to change the pitch of notes or create vibrato effects. New playing techniques, such as bending strings, tapping, hammering-on, using audio feedback, or playing slide guitar, can also change the sound of an electric guitar.
There are several types of electric guitars. Early models were hollow-body semi-acoustic guitars, while later models became solid-body. Common string configurations include the six-string guitar (tuned E, A, D, G, B, E from lowest to highest), the seven-string guitar (with an extra low B string), the eight-string guitar (with an additional low E or F# string), and the twelve-string guitar (with six pairs of strings, like a mandolin).
In rock music, the electric guitar often plays two roles: rhythm guitar, which creates the beat and plays chords, and lead guitar, which plays melodies, solos, and fills. In small groups, one guitarist may switch between these roles. In larger groups, there is often a separate rhythm guitarist and lead guitarist.
History
Many experiments were done to make the vibrations of string instruments louder starting in the early 20th century. Patents from the 1910s show that telephone transmitters were adapted and placed inside violins and banjos to amplify the sound. Hobbyists in the 1920s used carbon button microphones attached to the bridge; however, these detected vibrations from the bridge on top of the instrument, resulting in a weak signal.
Electric guitars were first made by people who built acoustic guitars and other instruments. The need for amplified guitars began during the big band era; as orchestras grew larger, guitar players realized they needed louder and electric guitars. The first electric guitars used in jazz had hollow archtop acoustic guitar bodies with electromagnetic transducers.
The first electrically amplified stringed instrument sold commercially was a cast aluminum lap steel guitar nicknamed the "Frying Pan," designed in 1931 by George Beauchamp, the general manager of the National Stringed Instrument Corporation, and Paul Barth, who was vice president. George Beauchamp, along with Adolph Rickenbacker, invented the electromagnetic pickups. Coils wrapped around a magnet created an electromagnetic field that converted the vibrations of the guitar strings into electrical signals, which could then be amplified. Commercial production began in late summer of 1932 by the Ro-Pat-In Corporation (Electro-Patent-Instrument Company) in Los Angeles, a partnership of Beauchamp, Adolph Rickenbacker (originally Rickenbacher), and Paul Barth.
In 1934, the company was renamed the Rickenbacker Electro Stringed Instrument Company. That year, Beauchamp applied for a United States patent for an Electrical Stringed Musical Instrument, which was later issued in 1937. By the time it was patented, other manufacturers were already making their own electric guitar designs. Early electric guitar manufacturers include Rickenbacker in 1932; Dobro in 1933; National, AudioVox, and Volu-tone in 1934; Vega, Epiphone (Electrophone and Electar), and Gibson in 1935; and many others by 1936.
By early-mid 1935, Electro String Instrument Corporation had success with the "Frying Pan" and released the Electro-Spanish Model B and the Electro-Spanish Ken Roberts, which was the first full 25-inch scale electric guitar ever produced. The Electro-Spanish Ken Roberts was revolutionary for its time, providing players a full 25-inch scale with easy access to 17 frets free of the body. Unlike other lap-steel electrified instruments of the time, the Electro-Spanish Ken Roberts was designed to be played while standing upright with the guitar on a strap, like acoustic guitars. It was also the first instrument to feature a hand-operated vibrato as a standard arrangement, a device called the "Vibrola," invented by Doc Kauffman. It is estimated that fewer than 50 Electro-Spanish Ken Roberts were made between 1933 and 1937; fewer than 10 are known to survive today.
A solid-body electric guitar is made of solid wood without air spaces that help produce sound. The first solid-body Spanish standard guitar was offered by Vivi-Tone no later than 1934. This model had a guitar-shaped body made of a single sheet of plywood attached to a wood frame. Another early, mostly solid Spanish electric guitar, called the Electro Spanish, was sold by the Rickenbacker guitar company in 1935 and made of Bakelite. By 1936, the Slingerland company introduced a wooden solid-body electric model, the Slingerland Songster 401 (and a lap steel counterpart, the Songster 400).
Gibson's first electric guitar, sold in 1936, was the ES-150 model ("ES" for "Electric Spanish" and "150" for the $150 price of the instrument, along with a matching amplifier). The ES-150 had a single-coil, hexagonally shaped "bar" pickup, designed by Walt Fuller. It became known as the "Charlie Christian" pickup, named for the jazz guitarist who was among the first to use it. The ES-150 gained some popularity but had uneven loudness across the six strings.
A working solid-body electric guitar was designed and built in 1940 by Les Paul using an Epiphone acoustic archtop as an experiment. He created a "log guitar"—a wood post with a neck attached and two hollow-body halves attached to the sides for appearance only. Gibson initially rejected these designs, which inspired the 1952 Gibson Les Paul, designed by Ted McCarty.
Feedback problems with amplified hollow-bodied electric guitars were understood early in the production of electric guitars. Gage Brewer's Ro-Pat-In of 1932 had a top so heavily reinforced that it functioned similarly to modern semi-hollow bodies.
Types
Solid-body electric guitars differ from acoustic guitars because they do not have a vibrating soundboard to amplify string vibrations. Instead, they use electric pickups, an amplifier, and a speaker. The solid body helps ensure that the amplified sound only comes from the strings, avoiding unwanted sounds like wolf tones and feedback that can occur with amplified acoustic guitars. These guitars are usually made from hardwood covered with a hard polymer finish, such as polyester or lacquer. In large factories, the wood is stored for three to six months in a wood-drying kiln before being shaped. High-quality custom guitars often use older wood that is fully dried, cured, and stable, making it less likely to warp.
One of the first solid-body guitars was invented by Les Paul. Gibson did not share their early Gibson Les Paul prototypes with the public because they believed the design would not be popular. Another early solid-body guitar, similar to the future Gibson Les Paul, was created in 1941 by O.W. Appleton of Nogales, Arizona. Appleton tried to share his "App" guitar idea with Gibson and Fender but was not successful. In 1946, Merle Travis asked steel guitar builder Paul Bigsby to create a solid-body Spanish-style electric guitar, which Bigsby completed in 1948. The first mass-produced solid-body guitars were the Fender Esquire and Fender Broadcaster (later called the Fender Telecaster), made in 1950, five years after Les Paul’s prototype. The Gibson Les Paul soon followed to compete with the Broadcaster. Another famous design is the Fender Stratocaster, introduced in 1954. It became very popular in the 1960s and 1970s because of its wide range of sounds and comfortable shape. Different guitar styles use various pickup types, such as 2 or 3 "single-coil" pickups or a "double humbucker," with the Stratocaster having three single-coil pickups.
Guitar World magazine has summarized the history of electric guitars. The earliest guitar on their list is the Ro-Pat-In Electro A-25 "Frying Pan" (1932), described as the first fully working solid-body electric guitar sold. It was used in a public performance by Gage Brewer in Wichita, Kansas, in October 1932. The most recent guitar on the list is the Ibanez JEM (1987), which had 24 frets, an extremely thin neck, and was designed for fast playing. Other important guitars on the list include the Gibson ES-150 (1936), Fender Telecaster (1951), Gibson Les Paul (1952), Gretsch 6128 Duo Jet (1953), Fender Stratocaster (1954), Rickenbacker 360/12 (1964), Van Halen Frankenstrat (1975), and Paul Reed Smith Custom (1985). Many of these guitars were improvements on earlier designs. Over time, electric guitars became culturally significant and visually recognizable, with companies selling small model versions of famous guitars, such as the Gibson SG used by Angus Young of AC/DC.
Some solid-body guitars, like the Gibson Les Paul Supreme, PRS Singlecut, and Fender Telecaster Thinline, have hollow chambers inside the body. These chambers are placed away from the bridge and string anchor point to avoid affecting the guitar’s structure. These are called "chambered bodies" by Gibson and PRS. The reasons for this design include reducing weight or achieving a semi-acoustic tone (explained below), or both.
Semi-acoustic guitars have a hollow body like acoustic guitars and electromagnetic pickups built into the body. They work similarly to solid-body electric guitars, but the hollow body also vibrates, so the pickups capture both string and body vibrations. Many models, called "semi-hollow bodies," include a solid block in the middle of the soundbox to reduce feedback. These guitars are not loud enough for live performances but can be played unplugged for quiet practice. They are known for producing soft, emotional, or funky tones and are used in genres like jazz, blues, funk, 1960s pop, and indie rock. They often have cello-style F-shaped sound holes, which can be blocked to reduce feedback. Unlike chambered guitars, which are made from a single block of wood, semi-acoustic guitars are made from multiple pieces of wood in an "archtop" shape, a construction method different from typical steel-string acoustic guitars. The top of a semi-acoustic guitar is made from a thick piece of wood that is carved into a curved shape, unlike the flat top of conventional acoustic guitars.
Some steel-string acoustic guitars have built-in systems to amplify their sound without changing their tone. These systems may include piezoelectric pickups under the bridge or a small microphone inside the guitar that converts body vibrations into electrical signals. Some guitars use both types of pickups with a built-in mixer or equalizer. These instruments are called electric acoustic guitars. They are considered acoustic guitars because the pickups capture vibrations from the guitar body, not directly from the strings. Amplification increases volume but does not alter the tone.
Construction
Electric guitar design and construction vary in the shape of the body and the arrangement of the neck, bridge, and pickups. However, many parts are common on most guitars. The image below shows the different parts of an electric guitar. The headstock (1) holds the metal machine heads (1.1), which use a worm gear to adjust tuning. The nut (1.4)—a thin, strip-like piece made of metal, plastic, graphite, or bone—supports the strings at the headstock end. The frets (2.3) are thin metal strips that stop the strings at the correct pitch when the player presses them against the fingerboard. The truss rod (1.2) is a metal rod (usually adjustable) that helps keep the neck straight by balancing the tension of the strings. Position markers (2.2) help the player locate their position on the fingerboard.
The neck and fretboard (2.1) extend from the body. At the neck joint (2.4), the neck is either glued or bolted to the body. The body (3) is usually made of wood with a hard, polymerized finish. When the strings vibrate near the magnetic pickups (3.1, 3.2), they create an electric current in the pickup winding. This current travels through the tone and volume controls (3.8) to the output jack. Some guitars use piezo pickups instead of or in addition to magnetic pickups.
Some guitars have a fixed bridge (3.4). Others have a spring-loaded hinged bridge, also called a vibrato bar, tremolo bar, or whammy bar, which allows players to change the pitch of notes or chords or create a vibrato effect. A plastic pickguard on some guitars protects the body from scratches or covers the control cavity, which holds the wiring. The impact of wood and material choices on the sound of the amplified signal is debated. Some believe it is very important, while others think the differences are small. In acoustic and archtop guitars, wood choices clearly affect tone.
Common woods used in solid-body electric guitars include alder (bright but balanced), swamp ash (similar to alder but with stronger high and low tones), mahogany (dark, bass-heavy, and warm), poplar (similar to alder), and basswood (neutral). Maple, a very bright tonewood, is also used but is heavy, so it is often used as a "cap" on guitars made of other woods. Cheaper guitars often use less expensive woods like plywood, pine, or agathis, which are not true hardwoods and may affect durability and tone. While most guitars are made of wood, other materials like plastic, metal, or cardboard have also been used in some instruments.
The guitar output jack usually sends a monaural signal. Some guitars with active electronics use a jack with an extra contact, typically used for stereo signals. These guitars use the extra contact to disconnect the battery from ground when the guitar is not in use, saving battery life. A standard mono plug is needed to complete the connection and activate the battery. Most guitar cables use a high-impedance 1⁄4 inch (6.35 mm) mono plug, which has a tip and sleeve, called a TS phone connector. The voltage is usually about 1 to 9 millivolts.
A few guitars, like Rickenbacker models with Rick-O-Sound, have stereo output. Stereo effects are often achieved by sending signals from the neck and bridge pickups to separate outputs. These systems use a high-impedance 1⁄4 inch plug with a tip, ring, and sleeve, called a TRS phone connector. Some studio guitars, like certain Gibson Les Paul models, use a low-impedance three-pin XLR connector for balanced audio. Other specialized connectors support features like MIDI and hexaphonic pickups.
The bridge and tailpiece, though separate, work together to influence playing style and tone. There are four main types of bridge and tailpiece systems on electric guitars, each with many variations.
A hard-tail bridge anchors the strings at or near the bridge and is fixed to the top of the instrument. These are common on carved-top guitars like the Gibson Les Paul and Paul Reed Smith models, as well as slab-body guitars like the Music Man Albert Lee and Fender models without a vibrato arm.
A floating or trapeze tailpiece (like a violin’s) is attached to the body at the bottom of the guitar. These are found on Rickenbackers, Gretsches, Epiphones, archtop guitars, and the 1952 Gibson Les Paul.
A tremolo arm or vibrato tailpiece system uses a lever attached to the bridge to temporarily loosen or tighten the strings, changing the pitch. This allows players to create vibrato or portamento effects. Early vibrato systems were often unreliable and caused tuning issues. Later Fender designs improved reliability, but Fender held the patent for many years, so other companies used older designs for a long time.
After Fender’s patent on the Stratocaster-style vibrato expired, improvements to the system became available. Floyd Rose introduced one of the first major advancements in the 1970s with "locking" nuts and bridges that help maintain tuning during heavy use of the vibrato arm.
The fourth system uses string-through body anchoring, where the strings pass over the bridge saddles, through holes in the guitar body, and are secured at the back with metal ferrules. Some believe this design improves sustain and tone. Examples include the Fender Telecaster Thinline, Fender Telecaster Deluxe, B.C. Rich IT Warlock, Mockingbird, and Schecter Omen 6 and 7 series.
Unlike acoustic guitars, which have hollow bodies, electric guitars produce less audible sound when plucked. They are usually connected to an amplifier and speaker. When played, string movement generates a small electric current in the magnetic pickups, which are magnets wrapped with fine wire. The signal travels through the tone and volume controls to the output jack, then through a cable to an amplifier. The current’s strength depends on factors like string density and movement over the pickups.
Magnetic pickups can pick up unwanted electromagnetic interference, causing a hum at 50 or 60 cycles per second, depending on the local power supply frequency. This hum is strongest with single-coil pickups. Double-coil or "humbucker" pickups were created to reduce this hum by opposing it, hence their name. The combined inductance of the two coils also produces a fuller, richer tone.
Electric guitar necks vary in shape and materials. The main measure of a guitar neck is the scale length, which is the distance between the nut and bridge where the strings vibrate. A typical Fender guitar uses a 25.5-inch (65 cm) scale length.