But he was also schizophrenic. Extreme boisterousness could be punctuated by moods of deep depression, which brought on mental collapses and unsuccessful suicide attempts, his outward robustness concealling a certain fragility of both body and mind. At a time when musical opinion was against him, he rejected the notion that the symphony was dead. “No more dead than the novel,” he once said. By the time symphony writing became popular once more, Arnold had already composed nine.

A lot of his gloom was caused, especially during his middle life, by the scorn with which his music was treated in many quarters. He was convinced that Sir William Glock, when Controller of Music at the BBC, pursued a vendetta against him. Certainly Arnold’s compositions, melodious, often jokey and lightweight, were little to Glock’s taste and far too mainstream for a battalion of eager young Third Programme producers busily championing Stockhausen and Boulez. The reaction of a number of music critics only deepened the gloom; the term “Malcolm Arnoldish” was considered by them deeply pejorative.

With such resentment in his mind, much of which was justified, Arnold would take off to the pub and seek solace in alcohol. That simply added to his reputation of being difficult, antiintellectual and prone to shooting himself in the foot — as he quite literally did on one unfortunate occasion.

Once after having conducted the Bournemouth Symphony Orchestra, some of the players found him at a pub piano knocking out tunes and wearing only his underpants. The story, of a musician going from hushed concert hall to bar-room chord-bashing, is analagous with Arnold’s output: a continuity between the serious and the light-hearted.

But no one could accuse Malcom Arnold of being anything other than extremely fluent as a composer. When he was at his peak during his thirties his output was as huge as it was varied. Between 1951 and 1957 he wrote the scores for more than 80 films, culminating in the famous whistling adaptation of the Colonel Bogey march in The Bridge on the River Kwai which won him an Academy Award. He once claimed that he only wrote film music so that he could conduct it himself and so gain experience in this area. He may just have been teasing, because many of these scores were highly effective. During this period he also composed three operas and three ballets as well as a quantity of works for the concert hall.

But the great white hope of British music eventually found himself turned into an ogre who, many believed, was best left ignored. Gimmicky pieces, such as the Grand Grand Overture (1956), commissioned for a Hoffnung concert and scored for three vacuum cleaners, floor polisher, four rifles and orchestra, amused the public and provided fodder for youth orchestras, but failed to impress the critics. A new Arnold composition billed for the second half of a concert often found them leaving at the interval. Among orchestral players he was more admired. As an ex-performer he was adept at writing for solo instruments and well knew what could and could not be demanded from their players.

He lived long enough to enjoy something of an Indian summer. In the void left by the absence of successors to Stockhausen et al, Arnold’s music found a new respectability during the 1990s. So too did the man, who had finally beaten the bottle in 1987. The determination to self-destruct had evolved into a determination to be cast, at last, as one of the grand old men of British music. As the 21st century dawned, music had come full circle: tunes and melodies were once again in demand, and Arnold was at last appreciated.

Malcolm Henry Arnold was the youngest of five children from a well-to-do Northampton Methodist family involved in the footwear business. As a child he was asthmatic and needed to be carefully looked after by his mother, who was a fine pianist and a dominant figure in his childhood. His father also played the piano and organ and the young Arnold, who was educated privately, was widely exposed to music from a young age.

At the Royal College of Music he studied composition with Gordon Jacob and trumpet with Ernest Hall, but by the time he had completed his studies he was aware of his tendency towards schizophrenia. He joined the trumpet section of the London Philharmonic Orchestra in 1941, becoming principal almost immediately.

Despite originally registering as a conscientious objector, Arnold left the LPO to join the Army in 1944 which did little for his emotional wellbeing. He was furious when, after rigorous infantry training, he was drafted into playing cornet in a military band: hardly a major contribution to the war effort and a lowly post in comparison with the one he had given up. In frustration he shot himself in the foot — potentially a serious offence — and was discharged on medical grounds.

When he recovered Arnold went to the BBC Symphony Orchestra as a trumpet player and then rejoined the London Philharmonic in 1946. The same year the LPO recorded an overture he had written, Beckus the Dandipratt.

He had been composing since childhood, inspired, he once said, by a chance meeting with Duke Ellington in a Bournemouth tea room. Louis Armstrong was another influence. John Hollingsworth told him that the British film industry was lacking in men who could write agreeable background music. Arnold found he could answer such a need with ease and there followed a mass of movie scores, ranging from The Captain’s Paradise to The Inn of the Sixth Happiness. But this was not a time when the music establishment took kindly to — or could even comprehend — the concept of crossover music.

Arnold pressed on regardless. In 1948 he won the Mendelssohn Prize for composition, and, though married with a small daughter, took off for Italy. Upon his return he dedicated himself full time to composing and conducting. The demand for film music kept him in continuous and exhausting work for many years, sometimes writing as much as 50 minutes of music in just ten days. It also made him extremely rich. Although the Colonel Bogey march remains his best-remembered, his own favourite was the music for Whistle Down the Wind: “It’s simple, sentimental and helps the picture,” he said.

In many respects he worked too hard and too fast, churning out music like a conveyor belt. And as an artist he was unclassifiable: one moment there would be traces of serialism, the next a frivilous meoldy. Even more disconcerting for those who like to pigeon-hole their artists were the works in which he explored his own despair through the music: “I had to write it as a study in blackness”, he once said of his Ninth Symphony.

By the Sixties Arnold had become, with Britten and Walton, the most successful of the contemporary British composers in terms of income. But in one respect he was different: they had prestige and acceptability. Malcolm Arnold had no inclination to try to ingratiate himself with those who thought his music too “popular”. He never surrounded himself with a coterie. When he was in rollicking mood he would eat enormous meals, usually with a similar quantity of wine, and as a result could behave badly. When he was in the glums he would curse those who deliberately turned deaf ears to the music he wrote with deep purpose.

In the latter category comes the Double Violin Concerto, commissioned by Yehudi Menuhin (1962), a number of his ballet scores, including Homage to the Queen and Solitaire, and some of his symphonies. The Seventh Symphony, whose premiere he conducted with the New Philharmonia in 1974, was a musical depiction of his three children and showed Arnold in reflective, even sombre mood. Even more sombre was the close of the Ninth, which was first performed by an amateur orchestra under Sir Charles Groves before an invited audience.

He was a prodigious concerto writer — but only with a soloist in mind, and then not always mainstream classical soloists. Benny Goodman was the recipient of a clarinet concerto and Larry Adler of an offering for harmonica.

In common with certain other composers Arnold suggested that nine was the number on which to end his symphonic writing. It was, he said, the story of his life: “I had been through hell.” There had been a grim procession of lawyers, doctors, pills and a court order denying him access to his autistic son — and that was on top of the critics who offered such savaging remarks as “lightweight Neo-Romantic confection”, “ivory tower conservatism”, and “a product of a creative mind in an advanced state of disintegration”. A drugs overdose failed to kill him and he was left to live in despair.

By the mid-1980s he had sunk completely. Given two years to live by his doctors in 1984, he suffered two broken marriages as well as a Court of Protection order claiming jurisdiction over his professional affairs. A supportive social worker died, and after a failed attempt by a subsequent guardian to gain control of the future rights of his music, he was physically assaulted and thrown out on the streets.

When the BBC Omnibus programme celebrated his 70th birthday with a sympathetic programme, discreetly suggesting that he had been shabbily treated, not least by Broadcasting House, Arnold looked frail. His body had shrunk, although some of his words carried a little of the old pugnacity when be declared roundly to the cameras that he “had lived quite long enough”. One commentator said that he appeared to be “a melancholy clown”.

However, he continued for another decade and more, his spirits renewed by the patience and companionship of his carer and personal assistant, Anthony Day. The pair moved into Day’s Norfolk home from where Day helped to restore the composer’s health and also his financial position. He was also active in promoting Arnold’s music and encouraging him to compose once more. By his 80th birthday, Arnold had finally become much respected: his lifetime’s work celebrated, albeit belatedly, with an extensive series of concerts on Radio 3 as well as in concert halls around the country.

Malcolm Arnold was appointed CBE in 1970 and knighted in 1993.

He married Sheila Nicholson in 1941. They had a son and a daughter. He married Isobel Gray in 1963. They had a son, but that marriage also ended in divorce. From 1984 Arnold was cared for by his companion, Anthony Day.

Sir Malcolm Arnold, composer, was born on October 21, 1921. He died on September 23, 2006, aged 84.