The British classical music world is in shock after the sudden death of one of its most prolific talents.

Conductor Richard Hickox died, apparently of a heart attack, in his hotel room in Cardiff on Sunday. He was 60, the age at which it used to be thought conductors were coming into maturity.

He had been working with the BBC National Orchestra of Wales, of which he was a former principal conductor, on a recording of Holst’s Choral Symphony. Tomorrow night he was due to conduct the premiere of English National Opera’s new production of Vaughan Williams Riders to the Sea.

That gives a glimpse of the kind of workload Hickox would regularly take on. Since 2005 he was music director of Opera Australia, spending six months of the year there. He had apparently ruffled feathers among leading singers, which led to an unseemly squabble, yet had been offered a contract extension.

A runner-up in the famous 1974 conducting competition which launched Simon Rattle’s career, Hickox was a pro-active conductor who founded two orchestras, the City of London Sinfonia and the original instrument ensemble Collegium 90, with which he recorded the outstanding series of Haydn’s masses which he said gave him most pride and pleasure.

He is likely to be remembered above all as a champion of British music. His death, little more than two months after Sir Vernon Handley, means it has lost two of its high-profile interpreters.

The CBSO might be wondering about the curse of Vaughan Williams symphonies. Handley was due to conduct the Fifth only a few weeks ago, while Hickox was due here on December 17 to conduct the Birmingham premiere of the second, A London Symphony, in its original 1913 version.

Hickox’s recording of this, which won the coveted Gramophone  Record of the Year award in 2001, was startling. The symphony is 20 minutes longer than the familiar revised version and has a darker, more late-romantic feeling. He was given special permission to conduct it – initially on record only, by the composer’s widow.

He went on to record the complete cycle of Vaughan Williams’ nine symphonies and his interpretations were warmly welcomed by reviewers although, apart from the special case of A London Symphony, they were additions to an already well-supplied market.

His championing of the Williams operas, on the other hand, was truly pioneering. He succeeded in getting them out of cold storage, not only onto disc but more importantly the stage. I remember seeing him conduct The Pilgrim’s Progress in a semi-staged Royal Opera House production at Symphony Hall ten years ago. It was a revelation.

Hickox leaves a legacy of 300 recordings, most for the independent Chandos label. As well as helping to build the profile of such lesser lights as Rubbra and Alwyn, he recorded Tippett symphonies and Britten operas.