Before the National Youth Jazz Orchestra (NYJO) became an entity in 1965, aspiring young British jazz musicians often had little alternative but to create their own opportunities. It took the visionary zeal of the orchestra’s founder, Bill Ashton, who has died aged 88, to change the landscape of possibilities.

Once the NYJO had been set up, any ambitious youngster under the age of 26 could turn up at one of its weekly open rehearsals in London, take a turn on the bandstand and, if good enough, come back again, with any luck on a regular basis.

As well as honing their jazz solo skills, new arrivals would also learn how to meld effectively into a big band ensemble, while handling challenging music. They often made lifetime friendships too. Some began to write for the band, their experimental arrangements often needing adjustment, trial and error an invaluable aid to improvement and the knowledge acquired carried over into their later professional work.

One can spot ex-NYJO players in almost every facet of present-day British jazz and in many theatrical pit bands and session orchestras. Their overall competence is a testament to the training that the orchestra has afforded them, and Ashton was rightly proud of that.

Bill was born in Blackpool, Lancashire, where his father, Eric Ashton, ran the family’s baker’s sundries business. His mother, Zillah (nee Miles), died when Bill was seven, after which he was dispatched to a prep boarding school in Yorkshire that was run on austere lines; a generally dismaying experience. Along with his younger brother, Brian, Bill later boarded at Rossall school in nearby Fleetwood, where he began to play the saxophone and clarinet, having first come across a C-Melody saxophone which his father, an amateur musician, kept at home.

Ashton continued to play during his national service in the RAF, where he spent a year on the joint services Russian language course, exploiting a gift for linguistics that later culminated in a modern languages degree from Oxford University. While he was at Oxford in the mid-1950s, his drive and enterprise led him to found the Oxford University Dance Band (the Ambassadors), the OU Modern Jazz Club and the Oxford University Big Band.

After graduation he taught in France from 1960 to 1961, before returning to Oxford in 1962 to take a diploma in education. After again spending time in France, in 1963 he made for London, where he met Kay Watkins, a student nurse, and they married in 1966.

Initially Ashton taught French at Highbury Grove school in north London, where with a colleague, Pat Evans, a science teacher, they set about forming the London Schools Jazz Orchestra in 1965 with the percussionist Frank Ricotti as their first star participant. Sure that there were other talented young jazz musicians in local schools, they found and recruited the saxophonists Stan Sulzmann and Bob Sydor and the drummer Bobby Worth to be founder members along with Ricotti.

The group was later renamed the London Youth Jazz Orchestra and then the National Youth Jazz Orchestra, and Ashton became its de facto director in 1973, giving up his teaching post at St Clement Danes school in Hammersmith to do so. From then on he embarked on a whirlwind of activity, finding players, hosting rehearsals, arranging up to 40 concerts a year and organising school workshops.

The orchestra’s base was at Ashton’s home in Harrow, north-west London, where he built up a substantial library of arrangements, about 600 of which were commissioned from British writers and all of which were made available to other youth orchestras.

As funds were initially short, Ashton, acerbic and indomitable, depended on the money coming in from Kay’s position as a lecturer in health education. But the situation improved as sponsorship deals began to accrue, to the point where Kay became his administrative assistant, dealing with all the red tape inherent in keeping the band going.

It is impossible to pinpoint or list all those who passed through NYJO but Ashton’s policy was clear: anyone good enough is old enough. The trumpeter and educator Gerard Presencer and the saxophonist Nigel Hitchcock joined aged 12 and stayed, while the trumpeter-bandleader Guy Barker was 14 and the virtuoso trombonist Mark Nightingale was 16. Each has gone on to attain international fame, as have so many others of NYJO’s putative stars, notably the trombonist Eliott Mason, now a salaried member of Wynton Marsalis’s Jazz at Lincoln Center Orchestra, the best of its kind in the world. One other noteworthy recruit was the vocalist Amy Winehouse, who sang with the band for a few months in 2000: Ashton told me he dealt with more press inquiries about her than anything else in the band’s history.

He also wrote songs and lyrics for the orchestra, laid on tours to the US, Russia, Oceania and Turkey, edited its stylish colour magazine and ensured that there were regular recordings on its own NYJO label, with his son Miles as the in-house sound engineer. There were also annual seasons at Ronnie Scott’s, with Ashton as a quick-witted and funny emcee, animatedly identifying soloists and plugging their home towns.

Ashton’s full-time role as musical director and booster-in-chief endured for more than 40 years, until questions began to be asked about the wisdom of the NYJO having all its eggs in one administrative basket. A new board was formed in 2009 and Ashton became a reluctant retiree, replaced by the trumpeter Mark Armstrong, a former star NYJO soloist. The orchestra is now supported by Arts Council England with professional staff members.

Named as life president on his retirement, Ashton then formed his own big band, which played occasional dates. But the orchestra was his life’s work, and with his raison d’être removed, he chose to spend his final years quietly – a change indeed for a man who had been so committed to the task he had set himself.

Ashton’s 1978 MBE for services to jazz was advanced to OBE in 2010.

He is survived by Kay, their three children, Grant, Miles and Helen, and seven grandchildren, Cameron, Georgia, Alexandra, Ella, Felix, William and Monty.

• William Michael Allingham Ashton, jazz educator and band director, born 6 December 1936; died 8 March 2025

• This article was amended on 25 March. An earlier version stated that Brian was Bill’s older brother when he was in fact younger; he did not go to the Yorkshire prep school that Bill attended.