The Wall of Sound was an enormous sound reinforcement system designed in 1973 specifically for the Grateful Dead's live performances. The largest concert sound system built at that time, the Wall of Sound fulfilled lead designer Owsley "Bear" Stanley's desire for a distortion-free sound system that could also serve as its own monitoring system. Due to its size, weight and resulting expense, the full WoS was only used from March to October of 1974.

Augustus Owsley Stanley III was an American-Australian audio engineer and clandestine chemist. He was a key figure in the San Francisco Bay Area hippie movement during the 1960s and played a pivotal role in the decade's counterculture. Under the professional name Bear, he was the sound engineer for the Grateful Dead, recording many of the band's live performances. Stanley also developed the Grateful Dead's Wall of Sound, one of the largest mobile sound reinforcement systems ever constructed. Stanley also helped Robert Thomas design the band's trademark skull logo.