Jam session in the context of "Descarga"

Acid rock is a loosely defined type of rock music that evolved out of the mid-1960s garage punk movement and helped launch the psychedelic subculture. While the term has sometimes been used interchangeably with "psychedelic rock", acid rock also specifically refers to a more musically intense, rawer, or heavier subgenre or sibling of psychedelic rock. Named after lysergic acid diethylamide (LSD), the style is generally defined by heavy, distorted guitars and often contains lyrics with drug references and long improvised jams.

Compared to other forms of psychedelic rock, acid rock features a harder, louder, heavier, or rawer sound. Much of the style overlaps with 1960s garage punk, proto-metal, and early heavy, blues-based hard rock. It developed mainly from the American West Coast, where groups did not focus on the novelty recording effects or whimsy of British psychedelia; instead, the subgenre emphasized the heavier qualities associated with both the positive and negative extremes of the psychedelic experience.

A jazz club is a venue where the primary entertainment is the performance of live jazz music, although some jazz clubs primarily focus on the study and/or promotion of jazz-music. Jazz clubs are usually a type of nightclub or bar, which is licensed to sell alcoholic beverages. Jazz clubs were in large rooms in the eras of Orchestral jazz and big band jazz, when bands were large and often augmented by a string section. Large rooms were also more common in the Swing era, because at that time, jazz was popular as a dance music, so the dancers needed space to move. With the transition to 1940s-era styles like Bebop and later styles such as soul jazz, small combos of musicians such as quartets and trios were mostly used, and the music became more of a music to listen to, rather than a form of dance music. As a result, smaller clubs with small stages became practical.

In the 2000s, jazz clubs may be found in the basements of larger residential buildings, in storefront locations or in the upper floors of retail businesses. They can be rather small compared to other music venues, such as rock music clubs, reflecting the intimate atmosphere of jazz shows and long-term decline in popular interest in jazz. Despite being called "clubs", these venues are usually not exclusive. Some clubs, however, have a cover charge if a live band is playing. Some jazz clubs host "jam sessions" after hours or on early evenings of the week. At jam sessions, both professional musicians and amateurs will typically share the stage.