They made some of the cleverest and most inventive music of the 70s, but split up at the height of their success. 10cc come together for the first time in 36 years to explain where it went wrong

Forget the Stone Roses' comeback and the mooted (and denied) Smiths reunion: another great Manchester band has reunited. True, it is solely for the purpose of being interviewed by the Guardian. But it is the first time all four members of 10cc have spoken to the same publication, for the same article, since their split in 1976.

The reason they have "reconvened" is to discuss Tenology, a five-CD box set focusing on the pioneering pop music they made between 1972 and 1976, when their fast-paced, action-packed hits made them one of the biggest bands in Britain.

"Yes, in a way we're back together," says Graham Gouldman. "Only we're in a box, not a studio. Help!"

With Tenology, 10cc should finally get their due as the Fab Four of the 70s. Songs such as Donna, Rubber Bullets and The Dean and I were melodically ingenious, sonically inventive, radical yet hugely commercial, crammed with ideas and hooks. As for the four albums the original foursome made together, from 1973's self-titled debut to 1976's How Dare You!, they posit 10cc as the missing art-pop link between the Beatles of the White Album and the Blur of Parklife.

"We took on the mantle of the Beatles," agrees Eric Stewart, nominally 10cc's guitarist even if, like all the members, he handled other instruments and sang. He also functioned as the band's own in-house George Martin, largely producing and engineering their records, albeit with help from the others. "We experimented on every song – you'll never hear two that sound alike."

Ensconced at their Strawberry Studios in Stockport, 10cc – Gouldman, Stewart, Kevin Godley and Lol Creme – didn't just include four singers and musicians who dabbled with the recording console. They also all wrote together, in various permutations, which probably explains the super-diverse nature of the material: a Gouldman-Stewart composition would differ wildly from a Godley-Creme one, while a Godley-Stewart or Creme-Gouldman track would take another tack entirely.

"I'd forgotten how avant-garde some of our music was," says Godley, the drummer and singer whose ethereal falsetto was used to striking effect, despite him being the only member not to sing on a 10cc No 1 – that's Stewart on I'm Not in Love and Creme on Rubber Bullets, while the basso profondo on Dreadlock Holiday is Gouldman's.

Godley is perhaps thinking of Une Nuit a Paris, the nine-minute, three-part mini-opera that opens 1975's The Original Soundtrack, and inspired Queen to make Bohemian Rhapsody. "One magazine recently described it as 'an overreach'," he says, "but we were constantly testing the waters of what we could and couldn't do."

Gouldman (bass, guitar, mandolin, autoharp) is annoyed by the pigeonholing of 10cc as a "guilty pleasure" when their so-called "soft rock" was artfully jagged: imagine what Frank Zappa might have achieved had he assembled a pop group in Manchester. They were the kid brothers of invention.

"People would ask: 'What sort of music is it?' But it's not prog, it's not art rock – it's 10cc music," Gouldman says. He brings up the song Clockwork Creep from 1974's Sheet Music: "Who else would write a song about a bomb on an airplane – from the position of the bomb?"

For all the rapier satire and hyper-kinetic approach to songcraft, 10cc became hugely popular. Creme (guitar, keyboards), who grew up wanting to be a comic artist and brought that cartoon vision to bear on the music, was stunned by the scale of their success. "In those days, records sold in their thousands," he says of 10cc's many chart forays. "You needed to sell 40,000 to 50,000 a week to get in the top 10. I used to try to imagine thousands of people going out of their homes or work, into a record shop, to buy our track. It used to boggle my mind."

It was Creme who, after lending his comically high falsetto to Donna, The Dean and I and Rubber Bullets, came closest to being 10cc's frontman, at least in the early days. But then, 10cc had three other frontmen, what with Godley's more austere charisma – not forgetting Stewart, who had sung on two worldwide No 1s in the 60s with the Mindbenders, and Gouldman who had written hits for the Yardbirds, Herman's Hermits and the Hollies. Any one of them could have legitimately claimed the spotlight for themselves.

But there was hardly a rush to do that because in another sense they were all backroom boys – just before forming 10cc, they had been the session band for Neil Sedaka on his two "comeback" albums of the early 70s. They never intended to be pop stars, nor did they have much rock'n'roll in them – apart, Gouldman says, from the odd bit of creative vandalism when Godley and Creme, art-school graduates both, would doodle on paintings in hotel lobbies or lifts.

10cc at the height of their fame, in 1976 (left to right): Graham Gouldman, Eric Stewart, Lol Creme, Kevin Godley. Photograph: Erica Echenberg/Redferns

Rather, they were happiest in the studio, endlessly finessing their complex four-minute creations – the "professional wing" of Stewart and Gouldman would do their thing, and Godley and Creme would work their magic while stoned on lethal grass – what Stewart calls "their Benson & Hedges mindfuckers".

"Eric had already been a fully fledged pop star, but he wanted to get into production," Creme says. "We liked being backroom boys at Strawberry. I was horrified when we had to play live."

Really, 10cc were less rock stars than part of a Brill Building or Hollywood tunesmith tradition. "We weren't Zeppelin," Creme admits. "We were pop, albeit an extreme version. That's because we had four pretty odd minds. All sorts of things can happen when you're free and easy with ideas and encouraged by the other lunatics around you."

10cc peaked in the summer of 1975 with a supremely evocative piece of sustained mood music – all six minutes and 12 seconds of it – with a revolutionary soundbed of multitracked vocals and an ambiguous lyric that painted a sombre picture of young love. I'm Not in Love was a production milestone, one that has since won acclaim from Paul McCartney and Axl Rose, as well as 8m radio plays around the world. It also suggested the cerebral 10cc did have beating hearts.

Within a year, though, Godley and Creme had quit, to work on a guitar-based contraption called "the gizmo" and a triple album featuring comedian Peter Cook and jazz legend Sarah Vaughan, entitled Consequences. The bifurcation of 10cc revealed much about their component parts. By 1981 Godley and Creme's music had more in common with the brainiac funk of Talking Heads, and within a couple of years they had become video pioneers, directing promos for Frankie Goes to Hollywood and Peter Gabriel. Meanwhile, the smoother pop axis of Gouldman-Stewart continued as 10cc, enjoying considerable success with Deceptive Bends (1977) and Bloody Tourists (1978), although by the early 80s Stewart had lost an eye in a car crash and the music had lost much of its edge.

All agree they should have been adult enough to accommodate Godley and Creme's extracurricular activities and welcomed them back as and when they were ready to record as 10cc. But that didn't happen, and although Godley and Gouldman remain friends and Creme and Stewart keep in touch (they are brothers-in-law), Godley and Creme's partnership dissolved after 27 years in the late 80s and Stewart and Gouldman's relationship broke down soon after that.

A full-scale reunion, then, seems unlikely. And yet not reforming is more in keeping with 10cc's original spirit of adventurism and risk-taking.

"I remember seeing a programme on VH1 that brought dead bands back to life, and it was toe-curlingly embarrassing," says Godley. "If I didn't see a future, creatively, then I might be one of those people who dream about the past, but I'm not. It was fantastic for its time, but I have no delusions about recreating it." Consequently, he's now working on a music-sharing app.

Today, Creme (the only survivor of the 60s "beat boom" to become a member of a sampling/techno band, as he did when he joined Art of Noise in 1998) is in the Producers with Trevor Horn, Gouldman still tours as 10cc, and Stewart – arguably the one most affected by the fall-outs – makes music from his home studio in France.

They agree it was their lack of a coherent image that has meant 10cc have been replaced by Queen as representatives of 70s rock's giddily inventive wing. As Godley puts it: "We only had 50% of what's required for a successful cultural moment. We had The Noise, not The Look." Not that there are any hard feelings about Queen having picked up their baton. "I'd like to ram the baton up their backside," says Gouldman with some relish. He's joking, of course, but he is more serious when he says: "It's a tragedy that we didn't stay together. It was a flame that burned incredibly brightly, but we could have lasted so much longer." He allows himself a chuckle. "If you'll forgive the expression, we had quite long candles."