An electric guitar is a guitar that uses a pickup to convert the vibration of its strings into electrical impulses. The most common guitar pickup uses the principle of direct electromagnetic induction. The signal generated by an electric guitar is too weak to drive a loudspeaker, so it is amplified before sending it to a loudspeaker.
Electric guitars, especially the solidbody models, played a central role in the story of rock 'n' roll and its unassailable dominance of popular entertainment. Their flexibility as musical instruments, combined with low price and easy portability, marked a new era in the business of entertainment as well as its sound.
The modern electric guitar is a solid-body instrument, visually similar to the acoustic guitar, but thinner. It has no soundbox and no vibrating soundboard. It has six strings just like the acoustic guitar. It has a long neck like a guitar and typically fretted. The six strings are held in place with the tailpiece at one end of the instrument and by the tuning pegs at the end of the neck. The tuning pegs are mechanical screws. An electrical pickup is positioned under the strings near the bridge and turns the vibrations of the strings into electrical impulses that are sent to an amplifier. A 1/4" phono plug in the body of the instrument is used to connect to the amplifier. The electric guitar requires an amplifier to amplify the frequencies of the vibrating strings that are sensed by the pickup. The amplifier takes these signals and processes them into louder and often altered sounds that are then sent to a speaker so they can be heard. The amplifier and sound processors in the amplifier are what provides the range of sounds that make the electric guitar such a versatile instrument.
The electric guitar may be the most important and popular instrument of the last half-century in American music. Certainly its introduction brought a major change to American musical technology and has shaped the sound and direction of modern musical styles.
The selling point to musicians was volume. For the first time, a guitar could hold its own against the horn section, and guitarists could pick out melody lines instead of just strumming the rhythm. In the late 1930s, guitar pioneers Floyd Smith and Charlie Christian brought the electric guitar into the jazz world, and redefined the role of the guitar in the swing orchestra ensemble.
Electric guitar pioneers of the 1930s and 1940s included artists such as jazzmen Eddie Durham and Oscar Moore, country pickers Noel Boggs and Merle Travis, and blues masters T-Bone Walker and Muddy Waters. All experimented with the instrument's tonal and harmonic possibilities. In the process, other musicians, makers, and audiences started to pay attention to the new electric sound.
The idea of using electricity to create louder string instruments already existed by the end of the 19th century. But it was only during the 1920s and 1930s that engineers, makers, and musicians began to solve some of the challenges of electronic amplification.
A solid-bodied electric guitar, the Fender Stratocaster has steel strings and three magnetic pickups, the back, middle and front pickups. The back pickup, situated closest to the bridge, has an offset angle of about ten degrees towards the fingerboard underneath the lower strings to give them more fundamental content. Its treble pole angles toward the bridge to give those strings more high harmonic content. This gives a gradual brightening of tone across the strings from bass to treble. The Stratocaster has a switch that operates these pickups as individuals or in combination. This guitar is noted for its high pitched screams produced by the shape of the body and the single coil pickups.
Electric guitars are most often made with solid bodies since they depend upon electromagnetic pickups and amplifiers to produce the sound and are not dependent upon the resonance of the hollow body like the acoustic guitar.
Although the first solid-body electric guitar commercially available was the 1939 Slingerland, it wasn't until 1949 when the first successful solid-body electric guitar was sold by Leo Fender. The guitar was called the Esquire and later was renamed Broadcaster and finally took the name of Telecaster. Based on the success of the Esquire, the Gibson Guitar Company went back to famed guitarist Les Paul and looked at his designs that he had been promoting for over 10 years. Finally, in 1952 Gibson came out with (what would eventually be) the famous Les Paul model solid-body electric guitar. By the 1960's, the electric guitar reached maturity with the introduction of the semi-hollow body electric guitar (used by B.B. King and Chuck Berry) and the Fender Stratocaster (used by Jimmy Hendrix). Few major innovations in electric guitar design have been made since then.
The electric guitar is arguably the most prevalent and popular instrument of the last 50 years of American music. It has earned the dedication of millions of players who perform music ranging from Rock & Roll, Country, Blues, Jazz, Folk, Pop, Rap, Funk, and virtually every genre in between.