Wall of Sound (Grateful Dead)

The Wall of Sound was an enormous public address system designed specifically for the Grateful Dead's live performances in 1974. It was the brainchild of audio engineer Owsley "Bear" Stanley. The Wall of Sound fulfilled the band's desire for a distortion-free sound system that could also serve as its own monitoring system. The Wall of Sound was the largest concert sound system built at that time.

After Stanley got out of prison in late 1972, he, Dan Healy and Mark Raizene of the Grateful Dead's sound crew, in collaboration with Ron Wickersham, Rick Turner, and John Curl of Alembic combined six independent sound systems using eleven separate channels, in an effort to deliver high-quality sound to audiences. Vocals, lead guitar, rhythm guitar, and piano each had their own channel and set of speakers. Phil Lesh's bass was piped through a quadraphonic encoder that sent signals from each of the four strings to a separate channel and set of speakers for each string. Another channel amplified the bass drum, and two more channels carried the snares, tom-toms, and cymbals. Because each speaker carried just one instrument or vocalist, the sound was exceptionally clear and free of intermodulation distortion.

Several setups have been reported for The Wall of Sound:

This system projected high-quality playback at six hundred feet with an acceptable sound projected for a quarter mile, at which point wind interference degraded it. The Wall of Sound was the first large-scale line array used in modern sound reinforcement systems, although it was not called a line array at the time. The Wall of Sound was the perhaps the second-largest non-permanent sound system ever built. The Wall of Sound can be seen in The Grateful Dead Movie, a documentation of the series of shows played October 16-20, 1974 at the Winterland Ballroom.

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