The Mothers Of Invention
were at least three separate bands, depending on how you count them. The membership of the MOI over the years is in the dozens, but the band can be broken into three distinct periods.:
The band known as the Mothers Of Invention were originally a bar band known as the Soul Giants when guitarist Frank Zappa joined them and changed their name to The Mothers. They went through several minor line-up changes before signing as a five-piece with Verve. The name 'The Mothers' was considered too risque by the record company so 'out of necessity we became the Mothers of Invention'
The line-up on their first album, Freak Out! is Ray Collins (vocals), Frank Zappa (guitar), Elliot Ingber (guitar), Roy Estrada (bass) and Jimmy Carl Black (drums). Other than the departure of Ingber, and the occasional absence of Collins, this remained the core of the band that recorded Absolutely Free, We're Only In It For The Money, Uncle Meat, Cruising With Ruben And The Jets, Burnt Weeny Sandwich and Weasels Ripped My Flesh.
This band, often considered the period when Zappa did his best work, also featured at various times keyboard player Don Preston, multi-instrumentalist Ian Underwood, percussionists Billy Mundi and Art Tripp and horn players Bunk Gardener, Buzz Gardener and Motorhead Sherwood. This version of the band specialised in social satire, dadaist onstage pranks, and avant-garde instrumental music of astonishing complexity which would on a whim turn into doo-wop classics or Louie Louie.
This band disbanded in 1969, and Zappa went on to make the album Hot Rats with Underwood. Many of the rest of the band formed The Grandmothers, which was an on-off name for Preston, Bunk Gardener and Black, among others, for several decades.
The Flo & Eddie Years
On Zappa's next album after Hot Rats, Chunga's Revenge, he featured two vocalists, 'The Phlorescent Leech And Eddie' (later abbreviated to 'Flo & Eddie'). These were in fact Mark Volman and Howard Kaylan of The Turtles.
Zappa put together a new line-up of Mothers (from now on the band would sometimes be known as the Mothers of Invention and sometimes just the Mothers) around Flo & Eddie. The membership of this line-up shifted occasionally, but featured Aynsley Dunbar on drums as a constant. Most of the time the bass player was former Turtle Jim Pons, after earlier player Jeff Simmons quit, and the only members from the original MoI left were Underwood and Preston, who along with George Duke shared keyboard duties in the band, although all three players rarely played together. Jimmy Carl Black also made occasional guest appearances as a vocalist.
This band was more geared towards poppy comedy songs on the subject of sex, and is not a favourite among fans, but actually made some great music. They weren't together long however - after the film 200 Motels (in which Sherwood and Black appeared), they recorded only two more albums, both live (Filmore East 1971 and Just Another Band From L.A.) before Zappa was pushed off stage by a jealous fan, and hospitalised.
Flo & Eddie went off to have a career as a duo, taking Preston, Pons and Dunbar with them. This ended that line-up of the band and indeed the pretence that the band was a band as such rather than a vehicle for Zappa.
Ruth Underwood era
For the mid-70s, Zappa put out records as either solos or band efforts more or less at whim. Those put out as Mothers albums are Overnite Sensation, Roxy & Elsewhere, One Size Fits All and Bongo Fury (with Captain Beefheart). The band varied a lot more in those years than in earlier ones, but generally included Duke, drummer Chester Thompson, Bruce Fowler (bass) and Tom Fowler (trombone) (the Fowlers went on to join the Grandmothers, and rejoined Zappa for his last tour in 1988), Ian Underwood stayed for a few years, his wife Ruth Underwood became the mainstay of the band on percussion (her wonderful vibraphone playing is the best thing on many of the albums from this period) and saxophone player and vocalist Napoleon Murphy Brock was Zappa's onstage foil, effectively co-fronting the band.
This band, which many consider the tightest live band Zappa ever had, stayed together in various configurations until Zappa lost the rights to the Mothers' name temporarily in a contractual dispute, at which point he made a more or less clean break and went for a small 'rock group' for live work for many years.
Many of Zappa's archive releases from the late 80s and early 90s, while released as 'Zappa' albums, have a lot of 'Mothers' material on. Precisely what the difference is can only be settled by lawyers, but two releases that are entirely 'Mothers' are 'Ahead Of Their Time' (a live performance by the Estrada/Black/Preston version of the band) and 'Playground Psychotics' (a 2-CD set of Flo & Eddie- era material). You Can't Do That On Stage Any More vol 2 is a concert by the Underwood/Brock/Duke band, and a great one, but is a 'Zappa' album.