On June 1, 1974, several leaders on the British underground rock scene -- Soft Machine bassist Kevin Ayers, John Cale, Brian Eno and Nico -- joined forces for one memorable evening at the Rainbow Theatre in London. Thankfully, the show was recorded for the rest of the world to enjoy as well.

The idea for the concert came from Island Records A&R man, Richard Williams, who suggested it would be a interesting mix of artists and would help generate interest in the label which had, up to then, been associated primarily with reggae."I came up with the idea of doing a showcase concert at the Rainbow, and putting out a live album in record time," Williams told author Richie Unterberger in the book, 'White Light/White Heat: The Velvet Underground Day by Day.' Indeed, it was released less than a month later on June 28.

“They had all these cult people on the label," said Cale in a 1974 press release. "The idea was that if you put them all together you might sell enough to justify their presence.” All four artists were part of the Island stable. "I signed Cale and Nico to Island, and invited Eno and Phil Manzanera [Roxy Music] to work on Cale's album," Williams said.

Eno was a founding member of Roxy Music, and though he left after their second album in 1973, his influence has never left the group. Eno went solo, issuing two of the 1974's most eclectic and exciting albums, 'Here Come the Warm Jets' and 'Taking Tiger Mountain by Strategy.' A year earlier, he released the groundbreaking 'No Pussyfooting' album with King Crimson's Robert Fripp the previous year.

Ayers had first come into public view as a member of the Soft Machine, who shared stages with Pink Floyd in 1967 at places like the UFO Club. He left the Soft Machine following the release of their debut album, and, by 1974, had a clutch of great albums to his credit. Cale, meanwhile, had also left his first real home, the Velvet Underground, around the same time, also carving out a trail of his own great solo discs. Another Velvets associate, Nico, was also making unique and very personal records. In retrospect, it seems like a natural melding of styles and personalities for this concert.

Joining the four were future touring Who member John 'Rabbit' Bundrick on keyboards and guitarist Mike Oldfield, who was in the midst of huge solo success with his 'Tubular Bells' album. Former Soft Machine drummer and vocalist Robert Wyatt was also on hand. Coincidentally, the concert was exactly one year to the day that Wyatt tragically fell out of a window, leaving him paralyzed from the waist down.

The concert featured material from all the key players, with side one split between Eno, Nico and Cale. Eno and company deliver great renditions of 'Driving Me Backwards' and a blistering 'Baby's On Fire.'  Cale's haunting rendition of the Elvis Presley classic 'Heartbreak Hotel' took the song into an entirely different world than Presley had ever dreamed of. A certain incident (see below) may have helped supply the venom this night.

Nico's incredible take on the Doors' 'The End' is a hypnotic trip. Ayers is well-represented here with all of side two dedicated to his songs. Two of his finest, 'Shouting in a Bucket Blues' and 'Stranger in Blue Suede Shoes,' are show-stealers with the incredible guitar work of Ollie Halsall taking things skyward.

But the event was not without its own soap opera. Ayers had became involved with Cynthia Wells, Cale's wife. Wells had once been a famous groupie (under the nickname "Miss Cynderella") and, along with the more infamous Pamela Des Barres, a member of the GTO's. Cale learned of their fling shortly before they took the stage that fateful night.

Cale would preserve the incident on his next album 'Slow Dazzle' in the song 'Guts,' which features the opening line, "The bugger in the short sleeves f---ed my wife, did it quick and split." The two eventually mended fences and continued to work together over the years.

The album is only a teaser of what the entire show offered up, as much more material by one and all was performed that night. Ayers set also, coincidentally (?) included the dramatic 'It Begins with a Blessing, But It Ends with a Curse,' and the rollicking 'I've Got a Hard-On for You Baby,' featuring Cale on backing vocals.

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