From Wikipedia, the free encyclopedia
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,
[1][2] 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.
History

Schematic drawing of the Grateful Dead's wall of sound
Stanley and
Dan Healy and Mark Raizene of the Grateful Dead's sound crew, in collaboration with Ron Wickersham,
Rick Turner, and John Curl of
Alembic designed the sound reinforcement system in an effort to deliver high-quality sound to attendees of Grateful Dead concerts, which were drawing crowds of 100,000 or more at the time. The Wall of Sound combined six independent sound systems using eleven separate channels. 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.
[2]
Several setups have been reported for The Wall of Sound:
- 604 total speakers, powered by 89 300-watt solid-state and three 350-watt vacuum tube amplifiers generating a total of 26,400 watts of power.[3]
- 586 JBL speakers and 54 Electro-Voice tweeters, powered by 48 600-watt McIntosh MC-2300 amplifiers generating a total of 28,800 watts of continuous (RMS) power).[4][5][2]
This system projected high-quality playback at six hundred feet (180 m) with an acceptable sound projected for one-quarter mile (400 m), at which point wind interference degraded it. Although it was not called a line array at the time, the Wall of Sound was the first large-scale
line array used in modern sound reinforcement systems.
[6] The Wall of Sound was perhaps the second-largest non-permanent sound system ever built.
There were multiple sets of staging and scaffolding that toured with the Grateful Dead. In order to accommodate the time needed to set up and tear down the system, the band would perform with one set while another would "leapfrog" to the next show. According to band historian Dennis McNally, there were two sets of scaffolding.
[7] According to Stanley, there were three sets.
[8] Four semi-trailers and 21 crew members were required to haul and set up the 75-ton Wall.
Though the initial framework and a rudimentary form of the system was unveiled at
Stanford University's
Maples Pavilion on February 9, 1973 (every
tweeter blew as the band began their first number), the Grateful Dead did not begin to tour with the full system until a year later. The completed Wall of Sound made its touring debut on March 23, 1974, at the
Cow Palace in
Daly City, California.
[2] A recording of the performance was released in 2002 as
Dick's Picks Volume 24.
As Stanley described it,
The Wall of Sound is the name some people gave to a super powerful, extremely accurate PA system that I designed and supervised the building of in 1973 for the Grateful Dead. It was a massive wall of speaker arrays set behind the musicians, which they themselves controlled without a front of house mixer. It did not need any delay towers to reach a distance of half a mile [800 m] from the stage without degradation.
[9]