Acid rock

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. The style is generally defined by heavy, distorted guitars, lyrics with drug references, and long improvised jams. Its distinctions from other genres can be tenuous, as much of the style overlaps with '60s punk, proto-metal, and early heavy, blues-based hard rock. The term, which derives its name from lysergic acid diethylamide (LSD), is sometimes used interchangeably with "psychedelic rock", but may refer more specifically to a more musically intense subgenre or sibling to the psychedelic rock style. Acid rock distinguishes itself from other psychedelic styles by having a harder, louder, or heavier sound, and developed mainly from the American West Coast. Such American groups did not focus on novelty recording effects or whimsy as much as subsequent British psychedelia, and instead emphasized the heavier qualities associated with both the positive and negative extremes of the psychedelic experience. As the movement progressed into the late 1960s and 1970s, elements of acid rock split into two directions, with hard rock and heavy metal on one side and progressive rock on the other. In the 1990s, the stoner metal genre combined acid rock with other hard rock styles such as grunge, updating the heavy riffs and long jams found in acid rock and psychedelic-influenced metal.