Few conductors can claim to have carried out their profession since childhood, but Lorin Maazel, who has died aged 84, made his distinguished debut at the age of nine. Since then his various manifestations included violinist, composer, opera director, multilingual narrator and film-maker, and he claimed he could even have become a space scientist, but it is for an especially masterful art of conducting that he will always be remembered. Orchestral musicians may look back with less than the warmest affection, and a more collegial attitude in the world of music has turned its back on the title "maestro" by which Maazel liked to be referred, but he always maintained impressive results over one of the longest careers in the business.
In 1932, two years after his birth in Neuilly-sur-Seine, near Paris, Maazel's parents, Lincoln and Marie, moved the family back to their native America. It was there that the five-year-old began to study the violin with Karl Moldrem and conducting with Vladimir Bakaleinikoff, a friend of the musical family and associate conductor of the Los Angeles Philharmonic. Within a few years, the child was deemed ready for the podium and, after taking a rehearsal with Bakaleinikoff's orchestra, made his official debut with the University of Idaho Orchestra, conducting Schubert's Unfinished (Eighth) Symphony. "You had to rub your eyes to believe it," wrote a critic of a New York appearance, "this chubby little figure in a white linen suit pace-making for an orchestra of seventy, and giving every cue on the dot."
The 11-year-old Maazel was invited to conduct Arturo Toscanini's NBC Symphony Orchestra, and after a rebellious show of defiance, the players quickly respected a good ear for mistakes and a memory which became legendary.
As with most prodigies, a reaction set in during Maazel's teenage years. While studying mathematics, languages and philosophy at Pittsburgh University, he also engaged his violin skills to lead both the Pittsburgh Symphony Orchestra and an associated string quartet. In 1951 a Fulbright scholarship took him to Italy to study baroque music, and his adult conducting career spread from a last-minute replacement in Catania to other European cities. At the age of 30 he became the youngest conductor (and the first American) to appear at Bayreuth's Wagner festival, in Lohengrin, and a post at the Deutsche Oper, Berlin, followed in 1965.
In the same year, he even directed the work he was conducting in Rome, Tchaikovsky's Eugene Onegin, working out the co-ordination of stage action to music well in advance. In the early 1980s, he professed respect for only two directors – Joseph Losey, for whose groundbreaking film of Don Giovanni (1979) he conducted the soundtrack, and Filippo Sanjust. But he also went on to work on other films he admired – Francesco Rosi's Carmen (1984) and Franco Zeffirelli's controversial, much-cut Otello (1986). He made his own short movie, A Week in the Life of a Conductor, for French television.
Maazel shone in the Italian operatic repertoire and among the highlights of over 300 recordings are several instalments in his Puccini cycles, but here, as in so much else, he was passionately engaged in what he most admired and altogether more aloof when the score posed fewer challenges.
A classic case was the saga of two recordings following performances at La Scala, where he was especially welcome from 1983 onwards: a revelatory approach to the orchestral complexities of Puccini's La Fanciulla del West in 1991, for which the Milanese players thundered their approval, was succeeded by a less than loving Manon Lescaut. The Maazel who received interviewers in his room at the studios was a difficult customer – abrupt, sarcastic and adamant that there was nothing to say about the work – in total contrast to the animated figure of the previous year, clearly in love with Puccini's most detailed score.
The contradictions had already been well established in Maazel's operatic dealings elsewhere. His overdue debut at the Royal Opera, London, with Verdi's Luisa Miller in 1978, brought an enthusiastic response: the man whose slogan might have been "call me maestro" went out and had a T-shirt blazoned with "I love opera!" But at the same time, one rehearsal with Covent Garden musicians broke down because the players felt he was making unreasonable and unsympathetic demands. The sorry end to Maazel's artistic and general directorship of the Vienna State Opera, a four-year contract which he had undertaken with such buoyant optimism in 1982, but which was curtailed in 1984, was on the other hand not his fault: the city's notoriously intransigent musicians had already conflicted with more amenable figures.
In the orchestral repertoire, he made a strong start: his Decca recordings of the 1960s, chiefly his Sibelius and Tchaikovsky symphonies, still have an impulsive freshness, and at least two of his Mahler symphonies, made with the Vienna Philharmonic in the 1980s, remain among the most expressive and finely balanced versions. His relationship with the Vienna Philharmonic extended to appearances as both violinist and conductor at the New Year's Day concerts, most recently in 1999 and 2005.
Less impressive, and typical of his concern for detail at the expense of the whole, warm-blooded organism, were his Strauss recordings with the Bavarian Radio Symphony Orchestra, of which he took control in 1993 for eight years for a supposedly record-breaking fee. In America, his tenure of the Cleveland Orchestra (1972-82) was criticised by his successor, Christoph von Dohnányi, as marked by an over-preoccupation with authoritarianism and beating time rather than phrase-making, but again the discipline could hardly fail to impress.
Following the Vienna debacle, he achieved equally distinguished results with the Pittsburgh Symphony Orchestra, where he was first consultant and then chief conductor from 1988 to 1996, and he quickly settled in to his stride as the music director of the New York Philharmonic from 2002, featuring John Adams's memorial to the victims of 9/11, On the Transmigration of Souls, in his first season.
Only at the beginning of this year did Maazel have to start making cancellations in a still-full conducting schedule; the reason given was an unspecified illness, which would eventually lead to his death from complications due to pneumonia. Having already conducted one Mahler cycle with the Philharmonia orchestra decades back, he had embarked on another. Critics were mostly baffled by the uniformly slow tempi and lethargic approach, which made singing very difficult indeed for a great artist such as the mezzo-soprano Alice Coote in a vocally extraordinary interpretation of Das Lied von der Erde. In June Maazel resigned from his post as music director of the Munich Philharmonic Orchestra and ceded to Semyon Bychkov what would have been a lavish celebration around Richard Strauss's 150th birthday with the Berlin Philharmonic.
Maazel's own achievement as a composer remained on a level with his contemporary André Previn. In interview with Adams, he remarked that, for composers, "there is nothing new under the sun. Everything has been used and done, so it's not the means you use, but how you use them."
But perhaps because, like Previn, his appetite for music as a conductor was so all-encompassing, he rarely transformed his own ingredients into something truly original. In 2005, he was much criticised for "buying" Covent Garden for the premiere of his opera based on Orwell's 1984. The score, slick, superficial and wedded to a simplistic libretto which made a travesty of its source, impressed few of its listeners. But as an honourable rendering of a new work, the performance was beyond reproach; and Maazel's superbly controlled conducting ensured that his music, for all its derivativeness, always sounded well.
Yet if the sum invested in the production was generally judged ill-spent, Maazel was beyond reproach in his fundraising efforts for organisations such as Unesco and the Red Cross. He was actively associated with the World Wide Fund for Nature and undertook an extensive tree-planting programme on his estate in Virginia. Together with his third wife, the distinguished German actor Dietlinde Turban, he founded the Chateauville Foundation in 1997 "to nurture children, foster art and reclaim the human spirit". He was to the last a ferocious force for good, both through his music-making and his wider sympathies.
Dietlinde and their two sons and daughter survive him, along with a son and three daughters from previous marriages.
• Lorin Varencove Maazel, conductor, born 6 March 1930; died 13 July 2014
