Wall of Sound (Grateful Dead)
Encyclopedia
The Wall of Sound was an enormous public address
system designed specifically for the Grateful Dead
's live performances by audio engineer Owsley "Bear" Stanley
. Used in 1974, 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.As Stanley described it,
, 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
.
The Wall of Sound consisted of 89 300-watt solid-state
and three 350-watt vacuum tube
amplifiers generating a total of 26,400 watts of audio power. 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 system
s , although it was not called a line array at the time. The Wall of Sound was the perhaps the second-largest* portable sound system ever built (although "portable" is a relative term). The Wall of Sound comprised two stages. One would go ahead to the next city to begin setup as soon as possible while the other was being used; the other would then "leapfrog" to the next show. 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 Roscoe 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. A recording of the performance was released in 2002 as Dick's Picks Volume 24
.
. This placed matched pairs of condenser microphones spaced 60 mm apart and run out of phase. The vocalist sang into the top microphone, and the lower mic picked up whatever other sound was present in the stage environment. The signals were added together using a differential summing amp so that the sound common to both mics (the sound from the Wall) was canceled, and only the vocals were amplified
Due to the lengthy installation time required for each venue, the Grateful Dead had three stages for the Wall of Sound. One would be in the process of being torn down from the previous concert, one would be in use, and the last would be in the next city being built as the present shows were being played. The three stages would thus leapfrog each other throughout touring. Four semi-trailer trucks and twenty-one crew members were required to haul and set up the 75-ton Wall.
The Wall was very efficient for its day, but it suffered from other drawbacks besides its sheer size. Synthesist Ned Lagin
, who toured with the group throughout much of 1974, never received his own dedicated input into the system, and was forced to use the vocal subsystem. Because this was often switched to the vocal mics, many of Lagin's parts were lost in the mix. Also, the Wall's quadraphonic format never translated well to soundboard tapes made during the period, as the sound was compressed into an unnatural stereo
format and suffered from a pronounced tinniness.
Public address
A public address system is an electronic amplification system with a mixer, amplifier and loudspeakers, used to reinforce a sound source, e.g., a person giving a speech, a DJ playing prerecorded music, and distributing the sound throughout a venue or building.Simple PA systems are often used in...
system designed specifically for the Grateful Dead
Grateful Dead
The Grateful Dead was an American rock band formed in 1965 in the San Francisco Bay Area. The band was known for its unique and eclectic style, which fused elements of rock, folk, bluegrass, blues, reggae, country, improvisational jazz, psychedelia, and space rock, and for live performances of long...
's live performances by audio engineer Owsley "Bear" Stanley
Owsley Stanley
Owsley Stanley also known as Bear, was an essential and transitional personality in the development of the San Francisco Bay counter-culture. Spanning the Beat-era years of Ken Kesey's Merry Pranksters scenes, he was equally pivotal to the explosion of 1960's Psychedelia culture...
. Used in 1974, the Wall of Sound fulfilled the band's desire for a distortion
Distortion
A distortion is the alteration of the original shape of an object, image, sound, waveform or other form of information or representation. Distortion is usually unwanted, and often many methods are employed to minimize it in practice...
-free sound system that could also serve as its own monitoring system
Foldback (sound engineering)
Foldback is the use of rear-facing heavy-duty loudspeakers known as monitor speaker cabinets on stage during live music performances. The sound is amplified with power amplifiers or a public address system and the speakers are aimed at the on-stage performers rather than the audience...
. The Wall of Sound was the largest concert sound system built at that time.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 from the stage without degradation." http://forum.lowcarber.org/showpost.php?p=6061756&postcount=1499
History
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 TurnerRick Turner
Rick Turner co-founded Alembic in 1970 and was involved in the design and construction of the Alembic instruments. He founded Rick Turner Guitars in 1979 and joined Gibson in 1988 where he served as president of Gibson Labs West Coast R&D Division.Turner left Gibson in 1992 and ran a guitar repair...
, and John Curl of Alembic
Alembic Inc
Alembic was founded in 1969 and is a manufacturer of high-end electric basses, guitars and preamps.-History:Ron and Susan Wickersham founded Alembic, Inc. in 1969...
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
Phil Lesh
Phillip Chapman Lesh is a musician and a founding member of the Grateful Dead, with whom he played bass guitar throughout their 30-year career....
's bass was piped through a quadraphonic
Quadraphonic
Quadraphonic sound – the most widely used early term for what is now called 4.0 surround sound – uses four channels in which speakers are positioned at the four corners of the listening space, reproducing signals that are independent of one another...
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
Intermodulation
Intermodulation or intermodulation distortion is the amplitude modulation of signals containing two or more different frequencies in a system with nonlinearities...
.
The Wall of Sound consisted of 89 300-watt solid-state
Solid state (electronics)
Solid-state electronics are those circuits or devices built entirely from solid materials and in which the electrons, or other charge carriers, are confined entirely within the solid material...
and three 350-watt vacuum tube
Vacuum tube
In electronics, a vacuum tube, electron tube , or thermionic valve , reduced to simply "tube" or "valve" in everyday parlance, is a device that relies on the flow of electric current through a vacuum...
amplifiers generating a total of 26,400 watts of audio power. 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
Line array
A line array is a loudspeaker system that is made up of a number of loudspeaker elements coupled together in a line segment to create a near-line source of sound...
used in modern sound reinforcement system
Sound reinforcement system
A sound reinforcement system is the combination of microphones, signal processors, amplifiers, and loudspeakers that makes live or pre-recorded sounds louder and may also distribute those sounds to a larger or more distant audience...
s , although it was not called a line array at the time. The Wall of Sound was the perhaps the second-largest* portable sound system ever built (although "portable" is a relative term). The Wall of Sound comprised two stages. One would go ahead to the next city to begin setup as soon as possible while the other was being used; the other would then "leapfrog" to the next show. 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
Stanford University
The Leland Stanford Junior University, commonly referred to as Stanford University or Stanford, is a private research university on an campus located near Palo Alto, California. It is situated in the northwestern Santa Clara Valley on the San Francisco Peninsula, approximately northwest of San...
's Roscoe Maples Pavilion on February 9, 1973 (every tweeter
Tweeter
A tweeter is a loudspeaker designed to produce high audio frequencies, typically from around 2,000 Hz to 20,000 Hz . Some tweeters can manage response up to 65 kHz...
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
Cow Palace
Cow Palace is an indoor arena, in Daly City, California, situated on the city's border with neighboring San Francisco, notable as a sporting arena.-History:...
in Daly City, California. A recording of the performance was released in 2002 as Dick's Picks Volume 24
Dick's Picks Volume 24
Dick's Picks Volume 24 is the twenty-fourth installment of the popular Grateful Dead archival series. It documents most of the concert from 3/23/74 at the Cow Palace in Daly City, California. The two-disc vault release is mastered in HDCD...
.
Technical challenges
The Wall of Sound acted as its own monitor system, and it was therefore assembled behind the band so the members could hear exactly what their audience was hearing. Because of this, Stanley and Alembic designed a special microphone system to prevent feedbackAudio feedback
Audio feedback is a special kind of positive feedback which occurs when a sound loop exists between an audio input and an audio output...
. This placed matched pairs of condenser microphones spaced 60 mm apart and run out of phase. The vocalist sang into the top microphone, and the lower mic picked up whatever other sound was present in the stage environment. The signals were added together using a differential summing amp so that the sound common to both mics (the sound from the Wall) was canceled, and only the vocals were amplified
Due to the lengthy installation time required for each venue, the Grateful Dead had three stages for the Wall of Sound. One would be in the process of being torn down from the previous concert, one would be in use, and the last would be in the next city being built as the present shows were being played. The three stages would thus leapfrog each other throughout touring. Four semi-trailer trucks and twenty-one crew members were required to haul and set up the 75-ton Wall.
The Wall was very efficient for its day, but it suffered from other drawbacks besides its sheer size. Synthesist Ned Lagin
Ned Lagin
Ned Lagin is an American avant-garde keyboardist.Lagin is considered a pioneer in the development and use of minicomputers in real-time stage and studio performance. This included running analogue to digital converters and doing digital signal processing to generate music in the era before digital...
, who toured with the group throughout much of 1974, never received his own dedicated input into the system, and was forced to use the vocal subsystem. Because this was often switched to the vocal mics, many of Lagin's parts were lost in the mix. Also, the Wall's quadraphonic format never translated well to soundboard tapes made during the period, as the sound was compressed into an unnatural stereo
Stereophonic sound
The term Stereophonic, commonly called stereo, sound refers to any method of sound reproduction in which an attempt is made to create an illusion of directionality and audible perspective...
format and suffered from a pronounced tinniness.