As the British counter-culture took shape in London in the mid-1960s, two bands were ever present at the various underground events and psychedelic happenings which marked its birth. One was Pink Floyd and the other was Soft Machine.

Hugh Hopper initially served as Soft Machine’s road manager and by the time he stepped up to become the bass player both groups were ready to move on from their roles as hippy house bands. While Pink Floyd went on to become mainstream rock stars, Hopper and Soft Machine pursued a less commercial but more progressive path to became the godfathers of British improvisational jazz-rock.

His compositions and virtuoso playing graced half a dozen seminal Soft Machine albums until 1973 when he left to pursue a variety of projects in the realms of experimental jazz and avant-garde art-rock.

In recent years he was reunited with other former Soft Machine members to tour and record variously as Soft Works and Soft Machine Legacy and continued to record and release a prolific string of solo albums until he was forced to cancel all engagements last year when he was given a diagnosis of leukaemia.

He had a phrase to describe his favourite musicians, whom he described as able to play the most avant-garde, improvised solos and yet bring a tear to the eye of the listener. He called them “hooligan romantics” and it was a billing he attempted to live up to throughout his career.

Born Hugh Colin Hopper in 1945 in Canterbury, Kent, by his mid-teens he had been drawn into a group of young musicians who shared a love of both American R&B and free jazz. They subsequently became known as “the Canterbury scene”, a rich seed bed that eventually produced not only Soft Machine but also Gong, Kevin Ayers & The Whole World, Caravan and Henry Cow.

The scene first stirred into life in 1963, when Hopper joined the Daevid Allen Trio, forming a rhythm section with the future Soft Machine drummer Robert Wyatt. Two years later he joined the Wilde Flowers which also included his brother Brian, Wyatt, Ayers and Richard Sinclair.

The group made little impact outside Canterbury but by 1966 had generated two spin-offs that were to have a major impact. Sinclair formed Caravan while Ayers and Wyatt teamed up with Allen and the organist Mike Ratledge to form Soft Machine.

Initially, Ayers, who was a strong singer and songwriter, took over the bass and Hopper found himself sidelined. But the Canterbury scene operated on a strong communal/collegiate ethic and Hopper became the band’s road manager, ever present as they joined Pink Floyd in providing the soundtrack at London’s earliest underground venues such as the UFO Club in Tottenham Court Road and Middle Earth and at events such as the 14 Hour Technicolour Dream, a key event in hippy folklore, held at Alexandra Palace in April 1967.

Hopper also contributed a composition to the group’s first album, released in early 1968. That year the group made two tours of America supporting the Jimi Hendrix Experience, but when Ayers left for a solo career at the end of the second tour, it appeared that Soft Machine would disintegrate.

However, partly they were contracted to record a second album, at the beginning of 1969 they had re-emerged as a trio comprising Ratledge, Wyatt and Hopper. Abandoning some of the surreal-Dadaist leanings of Allen and Ayers, the group moved into a more serious-minded fusion of jazz and rock that was defiantly uncommercial, but made them one of the first rock bands to be given kudos for their virtuosity as musicians. Their transition from dope-smoking heroes of the counter-culture to establishment-approved fusionists was completed in 1970 when they were invited to become the first rock band to appear at the BBC Proms.

Over the next few years various musicians came and went from the line-up. The arrival of the saxophonist Elton Dean and the reed player Karl Jenkins pushed them farther in a jazz-fusion direction, while the departure of Wyatt in 1971 to form Matching Mole diminished the group’s pop-rock leanings yet more.