Experimental rock

Experimental rock (originally known as avant-garde rock or avant-rock) is a subgenre of rock music that emerged in the 1960s. The genre emphasizes innovation over commercial appeal, incorporating influences and ideas lifted from avant-garde music through traditional rock music instrumentation. It is primarily characterized by its use of unconventional song structures, musical techniques, rhythms and lyricism, usually deemed challenging, difficult, inaccessible or underground.

Experimental rock was originally referred to as "avant-garde rock and roll" by music publications throughout the mid- to late 1960s. The earliest known use of the term was in 1966, in an issue of Sing Out!, which labelled New York City band the Fugs an "avant-garde rock and roll group". That same year, Record Research also used the term "avant-garde rock" in an issue describing the musical catalog of radio station WPMU, while the following year Canadian publication Take One used the phrase to describe California's the Mothers of Invention and the Gas Company, as well as New York's the Velvet Underground. By the late 1960s and 1970s, several music publications contributed to the wider popularization of the term, which was now also referred to as "experimental rock".

Experimental rock incorporates influences and ideas lifted from avant-garde music through traditional rock instrumentation. It is characterized by the use of unconventional song structures, techniques, rhythms, and approaches to lyricism not typically found in traditional rock music, often emphasizing innovation over commercial appeal, with artists frequently associated with "underground music". Artists drew influences from contemporary art movements such as dadaism, conceptual art, pop art and surrealism.

Although not associated with the avant-garde, during the early years of rock and roll, several artists experimented with the medium, creating innovative techniques that would become staples of the genre. In 1930, Les Paul became an early innovator of overdubbing, originally creating multi-track recordings by using a modified disk lathe to record several generations of sound on a single disk, before later using tape technology, having been given one of the first Ampex 300 series tape recorders as a gift from Bing Crosby. During the early 1940s–1950s, labels such as King Records, Sun Records, and Stax played a crucial role in the development of jazz, rhythm and blues, and early rock and roll, which were initially sidelined by the major companies alongside pioneering musical and production techniques, with Atlantic being the first label to make recordings in stereo, while Sun's Sam Phillips and Chess introduced slapback echo and makeshift echo chambers. Additionally, independent labels were often the only platforms available for marginalized African-American musicians in the U.S. at the time.

At the time, guitar amplifiers were often low-fidelity, and would often produce distortion when their volume (gain) was increased beyond their design limit or if they sustained minor damage. Between 1935 and 1945 guitarists such as Bob Dunn, Junior Barnard, Elmore James and Buddy Guy, experimented with early distortion-based guitar sounds. In early rock music, Goree Carter's "Rock Awhile" (1949) and Joe Hill Louis' "Boogie in the Park" (1950) featured an over-driven electric guitar style similar to that of Chuck Berry's sound several years later. By 1950, electric guitarists began "doctoring" amplifiers and speakers to emulate this form of distortion, which was also inspired by the accidental damage to amps, featured in popular recordings such as Ike Turner and the Kings of Rhythm song "Rocket 88" released in March 1951, where guitarist Willie Kizart used a vacuum tube amplifier that had a speaker cone slightly damaged in transport. Subsequent developments in rock music distortion were pioneered by guitarists such as Willie Johnson of Howlin' Wolf's band, Guitar Slim, Chuck Berry, Pat Hare of James Cotton's band, Paul Burlison of the Johnny Burnette Trio, and Link Wray throughout the 1950s.

On March 26, 1951, Les Paul released "How High The Moon", performed with his then-wife Mary Ford, and spent 25 weeks (beginning on March 26, 1951) on the Billboard chart, which included 9 weeks at #1. At the time, the song featured a significant amount of overdubbing, along with other studio techniques such as flanging, delay, phasing and vari-speed. Les Paul's advancements in recording were seen in the adoption of his techniques by artists like Buddy Holly. In 1958, Holly released "Words of Love" and "Listen to Me", which were composed with overdubbing for added instrumentation and harmonies.

Subsequently, the single "Space Guitar" by Johnny "Guitar" Watson, released in April 1954, showcased over-the-top guitar playing and the heavy use of reverb and echo effects, which influenced artists such as Bo Diddley, Ike Turner, Frank Zappa, and Jimi Hendrix.

Although experimentation had always existed in rock music, it was not until the early to mid-1960s that the genre widely began to incorporate influences from contemporary art, the avant-garde, and the wider art world. English artists such as members of the Beatles, the Who, the Rolling Stones, the Kinks, 10cc, the Move, the Yardbirds, and Pink Floyd attended and drew avant-garde ideas from art school, which they incorporated into a traditional rock and roll framework. Pete Townshend's avant-garde ideas which he learnt in art school such as that of auto-destructive art, inspired his guitar smashing in the Who, while others such as Syd Barrett drew influence from avant-garde music movements like free improvisation, particularly the prepared guitar techniques of AMM's Keith Rowe, which he incorporated into his psychedelic free-form guitar playing in Pink Floyd through the use of a zippo lighter as a guitar slide. Additionally, rock musicians drew from previous counterculture movements such as the Beat Generation, as well as contemporaneous developments in experimental film, literature, and music. Other early influences included avant-garde and free jazz, musique concrète, and the works of composers Igor Stravinsky, John Cage, Karlheinz Stockhausen, and Luciano Berio. Subsequently, early attempts to merge the avant-garde with rock music were made by several underground music acts such as the Druds, the Fugs, the Daevid Allen Trio, the Mothers of Invention, the Velvet Underground, Nico, Nihilist Spasm Band, Soft Machine, the Godz, Red Krayola, Hapshash and the Coloured Coat, Silver Apples, the United States of America, Cromagnon, Fifty Foot Hose, the Sperm, Pärson Sound, and Pink Floyd, who incorporated elements of avant-garde music, sound collage, and poetry into their work. Commercially successful British acts such as the Rolling Stones, and the Beatles would also incorporate avant-garde influences into their music, with the latter's songs "Carnival of Light" and "Revolution 9".