Shine on, you crazy diamond : ARTS : CLASSICAL MUSIC

IN JUNE 1943 a not very successful composer was on trial before Oxted magistrates for refusing to observe the conditions of his exemption from war service. That his name was Michael Tippett wouldn't have meant much to anyone at the time. But the c ase made news because he produced as a character witness the presiding genius of British music, Ralph Vaughan Williams, who told the court that Tippett's work was "a distinct national asset to increase the prestige of this country in the world".

As testimonials go it was impressive. But it failed to move the magistrates, and Tippett spent the next two months sewing mailbags in Wormwood Scrubs. Worse, it failed to move the British public, and Tippett spent the next 20 years trying to convince audiences, publishers, the BBC and (not always quick on the uptake) the critics that he was something more than a technically inept screwball. Given that he was approaching 60 before real recognition came, you could fairly call him a slow starter. And he bears comparison with Janacek in the way that he seems to have compensated for the delay by working on and producing major scores in extreme old age. For years now, every Tippett birthday has been marked by ritual surprise in newspapers and magazines that he could still look so comparatively young and still be writing with such energy and force.

But he was 90 earlier this month; and after the world premiere of his new orchestral score The Rose Lake at the Barbican in London on 19 February, there will, by his own admission, be no more. For years his eyesight has been weak, degenerating to the point where he could only write in an indecipherable scrawl on specially wide-spaced manuscript. Now he is nearly blind and can't even do that.

So the time has come for taking stock; and if you itemise it in print, Tippett's stock has an apparent conventionality. There are four symphonies, four concertos, three oratorios, five string quartets, five operas. His honours include a knighthood, Orderof Merit and Companion of Honour. And since the death in 1976 of Sir Benjamin Britten (whose incomparable genius overshadowed him as it does every British composer after Purcell), he has been the grand-master of music in this country: seer-like, wizardly, engagingly eccentric, and impossible to interview because like all true seers he rambles.

But despite the oratorios and honours, he has never been a creature of the Establishment. Any establishment. As a composer he has sidestepped both the avant garde and English tonal schools, with the result that each assumes him to be in league with the other. And in broader terms, he has set himself up as the ultimate Engish refusenik: a socialist, pacifist gay whose nonconformity embraces the laudably serious (his opera The Knot Garden was probably the first in history to feature an openly homosexual relationship), the childishly frivolous (give him an honorary degree and he'll turn up to the ceremony in plimsolls with inked-on hearts) and the downright perverse. At Oxted in 1943 there was no need for him to have gone to prison. Other conscientious objectors, such as Britten and Peter Pears, kept both their liberty and their integrity by observing the rules of the system. Tippett just didn't like the rules.

It was much the same with his response to music. Tippett's earlier scores, especially the string pieces of the 1930s, 1940s and 1950s, belong to English Tradition, reaching back through the pastoralism of the early 20th century to Purcell and beyond him the Tudor madrigalists. Like other British composers of his time, Tippett was concerned to mark out a home territory distinct from the Teutonic- dominated musicology of mainland Europe. But what he took from the past he then freed from its contextual restraints - the rule-book of form and structure - in frenzied outpourings of densely interwoven dancing rhythms and cascades of notes. Critics today describe it as "ecstatic", "transcendental". In the 1940s-50s it was "crazy", "overwrought", "incompetent","unplayable". There was a famous incident in 1958 when the first performance of his Second Symphony broke down soon after it had started - to the undisguised pleasure of the leader of the orchestra, who had publicly said the piece was impracticable. When The Midsummer Marriage premiered at Covent Garden, newspapers ran articles with headlines like "This Opera Baffles Us Too, Say Singers".

But Tippett's selling-point as a composer has always been his ability to reconcile his transcendental other-worldliness with a concern for modern social issues. Where some composers work hermetically and self-sufficiently, he hears his work as metaphor, responsible to something other than itself. "For Stravinsky," he once told me in an interview, "Belsen didn't happen. For me it did. It's something that I have to know about." Much of his music is music of protest: like the piece that first brought him fame, the 1940s oratorio A Child of Our Time.

This work is, in a sense, the crucible of Tippett's creativity. His best-known, best-loved and most approachable score was written in response to the oppression of the Jews in Nazi Germany. But the theme is universalised in a libretto, by Tippett himself, which singles out socio-cultural division as the supreme evil of world history. At every level, says the libretto, the pursuit of good is the pursuit of harmony and healing. And if there is one idea to which the entirety of Tippett's work pays court, it is the line in A Child of Our Time that reads: "I would know my shadow and my light, so s hall I at last be whole" - an idea annexed from Jungian therapy but acknowledged by Tippett as "the only truth I shall ever say".

In 50 years he hasn't tired of saying it, and score after score has carried the same message to the point where you could say that the pursuit of common ground between uncommon worlds and languages has been his life's work. As a writer of music he has accommodated English Pastoral to the transatlantic urban raunchiness of jazz, soul and rock. As a writer of words he has done much the same, making urban myths from an unlikely synthesis of highbrow literary allusion and the doggerel of prime-time television. He likes to say that apart from Blake and Shelley, he's devoted to The Kids from Fame and Cilla Black. Hear any of the recent operas and you can believe it.

Tippett's operas are a problem. He writes his own words, a habit he fell into when T S Eliot declined an invitation to supply the text for A Child of Our Time. Eliot has a lot to answer for: Tippett texts are offbeat, pretentious and embarrassing attempts to marry seer-like prophecy with street-cred language of the moment. The words and music in these scores come joined at the hip, inseparably interdependent. But even if the operas don't amount to his best work - the string quartets and song cycles, I think, claim precedence - they are certainly the chief landmarks in his creative life, stationed at regular intervals through the past half-century.

The Midsummer Marriage is the most immediately attractive: a 20th-century revisitation of Mozart's Magic Flute with a central couple required to undergo a ritual trial of wholeness - knowing their shadow and light - before they can achieve a true relationship. Making sense of Tippett's dense, allusive symbolism isn't easy (you get more out of The Waste Land first time round) but the music is beguiling: Tippett's richest vein of uncontainable, free-wheeling early Fifties lyricism.

With King Priam, later in the Fifties, Tippett's sound-world changed to something harder, more astringent, more controlled. But not for long. It was a cleansing of the palate prior to another fairly rich course called The Knot Garden, a psycho-sexual fable of broken characters in search of healing that comes across like Iris Murdoch with music. Completed in the Sixties, it filters the luxuriance of Midsummer Marriage through the starkness of Priam into a tight structure which is probably the peak of Tip pett's operatic achievement. Thereafter, alas, it's downhill to The Ice Break (East-West conflicts in an airport lounge) and New Year (space-age travellers help frightened orphan come to terms with urban jungle) where he tries too hard to play young and hip.

Tippett's triumphs and failures can probably be attributed to the same cause: the determination to engage his own time and sing its brute songs with a lyric voice. He set himself a hard task, and in addressing it hasn't exercised strict enough self-censorship. But at best the voice of Tippett has been balm. To know the still beauty of the Little Music for Strings, the ecstatic elevation of The Heart's Assurance or the moment in the Triple Concerto when a smokily exotic calm enshrouds the score like ritual blessing from some ancient god, is to understand why Tippett's birthday festival at the Barbican is called Visions of Paradise. It also explains why Tippett's autobiography opens with a quote from Nietzsche: "One must have chaos inside oneself to givebirth to a dancing star." That's me, says Tippett in the book. And so it is.

! `Visions of Paradise' opens at the Barbican on 5 Feb (071-638 8891). `King Priam' opens at the Coliseum, 3 Feb (071-632 8300).