Acid House is a subgenre of house music that originated in Chicago in the mid-1980s, defined by the deep, squelching basslines produced by the Roland TB-303 synthesizer. While pioneered by Chicago artists like Phuture, the genre became the catalyst for a massive youth counterculture movement in the United Kingdom during the "Second Summer of Love" of 1988–1989.

This movement was centered around illegal warehouse parties and influential clubs like Manchester's The Haçienda, where the music's hypnotic and psychedelic sound, often combined with the use of the drug MDMA, fostered a sense of euphoric unity among attendees. In Belgium, Acid House crossed over with the Electronic Body Music (EBM) scene, resulting in the homegrown New Beat movement.

The associated fashion of the Acid House scene was loose, baggy, and utilitarian, featuring dungarees, brightly colored t-shirts, and bucket hats. The most iconic visual element of the subculture was the yellow smiley face, which became a universal symbol of the scene's hedonistic and carefree ethos. Acid House was instrumental in bringing electronic dance music to a mainstream audience in Europe and laid the foundation for the global rave culture of the 1990s.

Before the term "acid house" became established, a form of bassline-driven electronic music known as "Hi-NRG" (high energy) existed, tracing its origins to disco . Giorgio Moroder's productions for Donna Summer exemplify this early style, which stripped away funk elements. The earliest recorded examples of acid house are subject to debate. Sleezy D's " I've Lost Control ," released on vinyl in 1986, is a significant early record, though its precise creation date remains unknown. Charanjit Singh's 1982 album " Synthesizing: Ten Ragas to a Disco Beat " has gained attention in the 21st century, featuring Indian ragas fused with disco. The album prominently utilizes the Roland TB-303, making Singh an early adopter of the instrument for commercial releases. This record predates Phuture's " Acid Tracks " by five years. Initially a commercial failure in India, it was later rediscovered and re-released in the 2010s, causing comparisons to acid house and suggestions that it might be the style's first example. Suns of Arqa's " Ark of the Arqans " (1985) also influenced early acid house.

The initial acid house records were produced in Chicago, Illinois. Phuture, consisting of Nathan "DJ Pierre" Jones, Earl "Spanky" Smith Jr., and Herbert "Herb J" Jackson, is credited with the first use of the TB-303 in house music. Prior uses of the TB-303 include Charanjit Singh's 1982 album, hi-NRG productions, and Alexander Robotnick's 1983 work. Phuture's 12-minute track " Acid Tracks " was recorded and played by DJ Ron Hardy at the Music Box. Hardy's repeated plays of the track contributed to its popularity. Chicago's house music scene faced police crackdowns on parties and events, leading to a decline in record sales by 1988. Simultaneously, acid house was gaining popularity in Britain.

London's Shoom club, opened in November 1987 by Danny and Jenny Rampling, was among the first to introduce acid house to the UK. The club's atmosphere, characterized by fog and dreamy ambiance, contributed to its exclusivity. This period marked the beginning of the "Second Summer of Love," a movement associated with a decrease in football hooliganism. Nicky Holloway opened Trip in June 1988 at the Astoria, catering specifically to the acid house scene. Trip was known for its late hours and frequent police attention. Due to anti-club laws, after-hours clubbing was illegal in London, leading to the emergence of raves in warehouses and other secret venues. Groups such as Sunrise and Revolution in Progress (RIP) organized these events. Sunrise held large outdoor events, while RIP was known for its warehouse parties. Promoters also moved raves into established clubs, continuing the scene.

Sunrise's large acid house raves attracted significant press attention, particularly regarding drug use. The association of acid house with drugs like ecstasy and LSD became prominent in the UK and Ibiza. This connection was also noted in New York City by late 1988. Mainstream press coverage increasingly focused on this association, despite differing accounts.

Acid house also became popular in Manchester. The Thunderdome was a central venue, giving rise to acts like A Guy Called Gerald and 808 State. Peter Ford and Richard Salt's " Oochy Koochy ," released as " Oochy Koochy (FU Baby Yeah Yeah) " by Baby Ford, is considered the first British acid house track. The genre was popular among football hooligans, providing a space for rival gangs to mix peacefully. The " Madchester " movement saw acid house influence the Manchester rock scene, with bands like the Stone Roses and Happy Mondays incorporating elements of the genre.

British news media devoted increasing coverage to the acid house scene, initially with positive promotion. However, coverage shifted to a negative viewpoint, focusing on the association with drugs. The Sun's coverage exemplified this shift, from promoting acid house to sensationalizing its connection to ecstasy. This coverage led to a crackdown on clubs and venues playing acid house. Records mentioning "acid," such as D Mob's " We Call It Acieed ," were removed from radio and television playlists. Despite this, " Stakker Humanoid " by Brian Dougans achieved mainstream success, reaching number 17 in the UK charts.

Acid house parties, typically held in abandoned warehouses, featured acid house and acid techno music, characterized by the Roland TB-303's sound. Promoters like Energy, Biology, Genesis'88, Sunrise, and Weekend World organized these events. Information about the parties was spread through flyers and word of mouth. Entry fees were kept low, and some parties were opened for free when police intervened. The music featured the "squelching" bass of the TB-303 and repetitive beats. Notable tracks include " French Kiss " by Lil Louis and " I've Lost Control " by Sleezy D. The catchphrase "Can you feel it?" was common among partygoers.

The Second Summer of Love, beginning in 1988, saw the rise of acid house music and unlicensed raves. It was associated with outdoor gatherings and the underground club scene. Five DJs were inspired to start these events after visiting Ibiza in 1987. The smiley face became a symbol of the period. Baggy clothing and the provision of water and Lucozade were common features. Acid house and hip house were typical of the era. Pirate radio stations promoted the music. Ecstasy was the primary drug used, contributing to feelings of euphoria and reducing violence. Media coverage shifted from positive promotion to sensationalizing the association with drugs.

Acid house visuals were defined by distinctive flyers and the ubiquitous smiley face symbol. In 1988, Danny Rampling commissioned George Georgiou to design a flyer for his club night Shoom, stipulating the inclusion of a smiley face. Georgiou modified the symbol, rendering it three-dimensional and altering its expression, which was then interpreted as an allusion to the drug Ecstasy. Shoom is considered one of the first acid house club nights in Britain.

Flyers served as essential promotional tools in the pre-internet era, featuring basic designs with club names and addresses, or imagery taken from comic books. Genesis, a promoter of large-scale raves, used flyers to convey an appearance of legitimacy, despite their events being largely illegal. Paul Oakenfold's Spectrum night introduced full-color flyers, designed by Dave Little, incorporating elements of 1960s psychedelia . These flyers are now considered collectible, serving as tangible pieces of history of rave culture.

The flyers were integral to the acid house scene, facilitating communication about events and locations, especially for illegal raves. They acted as guides to parties in warehouses and other unconventional venues, and were often distributed at clubs or passed among attendees. Collectors like Dave of Phatmedia amassed extensive collections, recognizing the flyers' artistic and historical value. The designs varied widely, from futuristic landscapes to bold typography. The flyers documented the evolution of the scene, from small gatherings to large-scale events, and are seen as artifacts of a significant cultural movement.

Acid house fashion, which reached its peak popularity in the late 1980s and early 1990s, was characterized by a distinct style reflecting the era's music and culture. Key elements included the widespread use of the smiley face, symbolizing the movement's focus on happiness and euphoria. This symbol, popularized by clubs like Shoom, appeared on clothing and accessories. Bandanas and bucket hats were common accessories, with bandanas possibly linked to an association with an outlaw image. Dungarees, worn oversized, were a staple garment, often paired with baggy T-shirts. Clothing featuring the words "trip" or "acid" was also prevalent, reflecting the culture's connection to psychedelic experiences. Bright colors and patterns, including neon and tie-dye, were common, mirroring the music's style. Sunglasses were frequently worn, possibly due to the intense lighting at raves and the tendency for events to last until sunrise.

The fashion was not merely aesthetic; it served as a means of nonverbal communication among participants. Comfortable, loose-fitting clothing was preferred, allowing for ease of movement during extended periods of dancing. European labels like Chipie, Lacoste, and Naf Naf gained popularity, followed by American sportswear brands such as Russel Athletic and Champion. Trainers, including Adidas Torsions and Nike Cortez, became a central part of the attire. The inclusive nature of the acid house scene contributed to the breakdown of traditional sartorial barriers.

The influence of acid house fashion extended beyond the immediate era, contributing to a lasting shift in fashion norms. The relaxed, sportswear-influenced style that emerged became a lasting trend, influencing subsequent generations. The casualization of dress codes, including the acceptance of trainers and sportswear in various settings, is attributed in part to the cultural impact of acid house.

Acid house music is characterized by repetitive basslines generated by the Roland TB-303 synthesizer. The TB-303's sound is achieved through modulation of the filter cutoff frequency at high resonance, often with added distortion, producing a "squelching" sound. This sound is paired with a four-on-the-floor beat, typically from the Roland TR-808 drum machine.