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The Plastic Ono Band is a band formed by John Lennon and Yoko Ono in 1969 as a vehicle for their collaborative and solo projects. Lennon and Ono had begun a personal and artistic relationship in 1968, collaborating on several experimental releases. Following their marriage in 1969, they decided that all of their future endeavours would be credited to a conceptual and collaborative vehicle, Plastic Ono Band. The band would go on to feature a rotating lineup of many musicians, including Eric Clapton, Klaus Voormann, Alan White, Billy Preston, Jim Keltner, Delaney & Bonnie and Friends, and Lennon's former Beatles bandmates George Harrison and Ringo Starr.

Lennon and Ono left the UK to settle in New York City during the fall of 1971. In Greenwich Village, the couple became more politically active and began writing protest songs. These songs became the basis for their next album, Some Time in New York City. As backing, they enlisted the help of New York band Elephant's Memory, consisting of guitarist Wayne 'Tex' Gabriel, bassist Gary Van Scyoc, saxophonist Stan Bronstein, keyboardist Adam Ippolito, keyboardist John La Boosca, and drummer Richard Frank, Jr. Phil Spector produced, and Jim Keltner also played on the album. The album was released on 12 June 1972, credited to "John & Yoko/Plastic Ono Band with Elephant's Memory plus Invisible Strings". Some Time in New York City included a second disc, entitled Live Jam, which included the recordings from the 1969 Peace for Christmas concert and the 1971 performance with Frank Zappa.  Ono and Lennon continued their work with Elephant's Memory throughout 1972, performing as the Plastic Ono Elephant's Memory Band (which also included Jim Keltner). On 30 August, they performed a pair of benefit concerts at Madison Square Garden. The benefit, entitled "One to One", was organised by Geraldo Rivera to raise money for children with mental challenges. By this time, La Boosca had departed the band, and the concert saw the addition of John Ward on bass. The concert was filmed and recorded, later released in February 1986 as the album Live In New York City. They also performed at the Jerry Lewis MDA Labor Day Telethon.  The last collaboration of the Plastic Ono Elephant's Memory Band was Ono's double album Approximately Infinite Universe. It was recorded throughout the fall of 1972, and was released in January 1973.
Plastic Ono Band