One of Frank Zappa’s most fascinating and divisive bands will be celebrated in a new box set, The Mothers 1971, out March 18.

The eight-CD package — an expansion on the 1971 live LP Fillmore East - June 1971 –  includes all four shows staged at New York City’s Fillmore East venue on June 5 and 6 of that year (including the famous encore with John Lennon and Yoko Ono) and a performance from London’s Rainbow Theatre on Dec. 10.

Zappa’s lineup at the Fillmore featured Zappa (vocals, guitar) with Ian Underwood (woodwinds/keyboards), Jim Pons (bass), Aynsley Dunbar (drums), Bob Harris (keyboards/vocals), vocalists Howard Kaylan and Mark Volman (aka “Flo & Eddie” of the Turtles) and guest keyboardist Don Preston. The finale show became one of Zappa’s most notorious for featuring Lennon and Ono during the encore, including a version of “King Kong” that led into an experimental jam later titled “Scumbag.”

The 100-track, 10-hour box also features a previously unreleased “hybrid concert” sampling shows from June 1 and June 3 in Scranton and Harrisburg, Penn., along with a homemade radio spot (plus related outtakes) and the rare single for “Tears Began to Fall” and its non-LP B-side “Junier Mintz Boogie” — the latter tunes re-released for the first time in 50 years.

The physical edition includes a 68-page booklet containing an interview with Mothers multi-instrumentalist Underwood (as conducted by Ahmet Zappa), along with recollections from Pons and others.

The Mothers 1971 will also be available to stream and download. Meanwhile, the material will also be issued as two separate three-LP vinyl releases: Fillmore East 50th Anniversary Edition and Rainbow Theatre. Pre-order details and track listings are available at the Zappa site.

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