Acid Rock

Originating in the mid-1960s from the intersection of American garage rock, blues, and British psychedelia, Acid Rock is defined by its heavy, distorted, and guitar-centric sound. The genre foregrounds long, instrumental improvisations, often structured around a single modal jam, and is sonically characterized by the prominent use of effects like fuzz, wah-wah, and phasing. Lyrically, it moved beyond standard rock themes to explore surreal, drug-inspired, or socially conscious subject matter. Its commercial peak in the late 1960s was brief, but its amplification and improvisational ethos directly shaped the development of hard rock and heavy metal.