Marco Polo is an opera like no other. The title role is taken by two singers, one Marco, the physical being, sung by a woman; the other Polo, representing memory, sung by a man. Other characters include Dante, Shakespeare, Mahler, Kublai Khan and Li Po (sung by a Peking Opera singer). The libretto is by Paul Griffiths, an English music critic whose novel Myself and Marco Polo persuaded Tan that he had found his ideal collaborator. The opera is not an adaptation of the novel, but explores certain preoccupations of both composer and librettist, "not like Western opera," says Tan, "and not like Eastern opera, but with many layers, many journeys across many cultures, many kinds of music."
This is imaginative history, and Tan's orchestra likewise stretches conventional boundaries, with a Western orchestra augmented by sitar, tabla, Chinese popa, Tibetan horns, singing bowls and bells. Tan's mixing has led some British critics to pooh-pooh his work as "crossover", but that takes no account of a life that could hardly fail to generate a synoptic approach to music. Tan was born in 1957 in Hunan province, China:" a place that almost no Western music had touched. It was too far from urban culture. Until I was almost 20 I had never heard Western composers, only my own culture, where music is part of life, in local kunqu theatre, or shamanistic ritual, mostly at weddings and funerals. I started playing Chinese folk instruments, bamboo flutes and the erhu two-string fiddle. Then when I was 10, I got a violin. Physically it was a violin, but culturally it was not, because it only had three strings, and as I had no money to replace the fourth string, I treated it as a three-string fiddle. In my early musical education there wasn't chamber music or symphonic music, only the theatre of rituals, real theatre in a ceremonial space, or beside a rice field, or in someone's home. To me making music is a theatrical thing. Whatever I write, I treat as part of an opera."
Living in rural China meant not only no Western music, but also a certain distance from Mao's Cultural Revolution, although Tan did spend two years of "re-education" in the rice paddies. "I was too young, I didn't understand what was happening," he says. "I didn't dare recall some of the things I saw until now. I remember when I was about nine years old, the Cultural Revolution had just started, and I was shopping with my grandmother in the city of Hunan. I suddenly saw a bunch of Red Guards join arms and jump from the top of a building crying, "Long live the Revolution, long live Chairman Mao." I simply did not understand what I was seeing."
The only music officially permitted during this period was propaganda opera and ballet, faint traces of which may have surfaced in his own work, notably Symphony 1997: Heaven Earth Mankind, composed for the reunification of Hong Kong with mainland China, and performed at this year's BBC Proms. Eventually, the Cultural Revolution subsided, more open-minded education became possible, and the Central Conservatory in Beijing re-opened. In 1978 Tan was among thousands who applied for a handful of places: "I was little more than a farmer; I had never seen a piano or any of those fancy instruments. I wasn't really competent. Some of the professors said. 'How can we accept him? He doesn't even know who Bach is'; another said, 'But he can improvise for three hours ...' At first they rejected me, and I cried, but a month later, I got a letter saying my case had been re-examined."
And so Tan travelled to Beijing to start a new life. "It was a 30-hour train journey, so my 'jet-lag' was terrible, but even worse was the culture- lag. I arrived in Beijing on the day that the Philadelphia Orchestra arrived to play Beethoven's Fifth Symphony. The professor who had argued on my behalf took me straight to the concert, and I dragged all my peasant- farmer baggage into the hall. I'd never heard of Beethoven. I'd never heard a Western orchestra before, and I'd never seen a conductor conduct so many musicians."
Initially that "jump" led him to abandon the traditions in which he'd grown up, but soon they reasserted themselves, as in his 1985 work On Taoism, which he recorded with the BBC SSO in 1992. The piece opens with Tan himself, howling and moaning like a Hunan shaman, before the orchestra enters with brooding power. Questions about whether it is an Eastern or Western work fade into irrelevance before the eerie insistence of the music, written to mark his grandfather's death. In 1986 Columbia University offered Tan a study-grant, and although he was at first forbidden to leave China, he eventually went to New York to take up his place.
Not that he knew what he was in for. "When I arrived, I took the subway from the airport to Manhattan, and I immediately understood that it wasn't at all the place I had imagined. I saw many people in the subway car, and they were all different colours. I asked myself, 'What country is this?' As Columbia was only paying my fees, I had to earn money to live, so I worked in restaurants and played my fiddles on the streets in Greenwich Village. That was my biggest classroom, and in some way it was very close to my village in China, with its ritual music and its religion. What I saw was a world culture of literature, poetry, painting, music, and that woke me up. I wanted to get away from the kind of depressing, bitter, atonal, selfish and super-intellectual post-post-whatever music I had been writing at Columbia."
Tan then began a series of works that revealed his unique vision, such as Paper Music (1993), "a ritual in sound and dance" written for an orchestra of recycled papers ("20 New York Times Magazines, 40 wax bread bags, two rolls of newspapers..."), stones and human voice. This is contemporary music that is bewitching, stimulating, even, heaven forbid, entertaining; music that, like Marco Polo, blurs distinctions between what is ancient and modern, between East and West. "It's not a question of following trends, or feeding trends," Tan says. "We are not trying to bring together the East and the West, but the East and the West pull us together: there is no other way."
Tan meanwhile has a cluster of new commissions, including, for Tokyo in 2002, an opera about the 7000-year history of tea: "the most important plant, an invisible bridge of communication, of harmony, of exchange" he says, and another work for New York's Metropolitan Opera in 2005. More immediately, he is writing a place for the very august New York Philharmonic, a Concerto for Water and Orchestra. Water is one of Tan Dun's favourite instruments. He incorporated it (alongside Bach and Chinese pipa in his Ghost Opera, written in 1994 for the Kronos Quartet; and in Peony Pavilion, his spectacular collaboration with director Peter Sellars, seen at London's Barbican Centre in September. In his work-room, there is a beautiful bowl filled with water, and as we talk he demonstrates how he deals with those moments in the creative process when the brain closes down; he dips his hand in the water, then allows it to trickle through his fingers, back into the bowl. The sound is as soothing, and as energising as a babbling brook. Tan Dun's work shares that sense of returning music to its elemental origins, and in so doing it suggests a way of discovering its future.
Tan Dun conducts 'Marco Polo': Huddersfield Town Hall (01484 430528), 22 November; Barbican, EC2 (0171 638 8891), 24 November; BBC Radio 3 broadcast 6.30pm 28 November. 'Marco Polo' is available on CD (Sony).