A classical chamber orchestra on the opening night of the London Jazz Festival with a Tunisian oud player? Purists on every side must have been steaming from all orifices. But this is the future of music. And it works, as this exhilarating fusion showed.

Nothing demonstrated that better than Arvo Pärt's 1977 minimalist classic, Fratres. It opened the concert, played “straight” by the excellent strings of the Britten Sinfonia under Joanna MacGregor's direction, with its elegiac refrain rising and falling over a drone like a sombre ritual. Then, at the end, it was repeated as an encore - but with a difference. This time the great Dhafer Youssef and the virtuoso percussionist Satoshi Takeishi added a subtle, shadowy patina of Arabic cries and whispers. It was as if the ancestral Estonian modes summoned by Pärt in Northern Europe had stirred strange, kindred echoes in North Africa. Pure musical magic.

And it wasn't the only heartstoppingly beautiful moment in this “East meets West meets North meets South” programme. Youssef's own pieces - gentle-spirited, syncopated improvisations in sophisticated metres, showcasing his stunningly pure voice (electronically enhanced with overlapping echoes), his shofar-like falsetto, and dextrous fingerwork on his Arabic lute - gained a dimension, sonically and expressively, when accompanied by the strings. Meanwhile, Takeishi, squatting beside his exotic drums and cymbals, supplied deft and supple solos, as did the ubiquitous jazz bassist Peter Herbert. And the Britten Sinfonia brought to the party some cool culture-hopping of its own. With MacGregor at the piano and Jacqueline Shave supplying fleet-fingered fiddle solos, it played three of MacGregor's exuberant arrangements of songs by the renowned Romanian gypsy singer Gabi Lunca.

Then Shave led two evocative pieces by Bartók. The Burletta from the Sixth Quartet was properly savage. But Pe Loc from the Romanian Folk Dances was the real show- stopper, with Youssef's voice and Takeishi's brushed drums again adding a mysterious and mystical subtext. No, Bartók didn't write it like that. But yes, that dedicated follower of folk fashion would have loved the intrusion.

Editor's choice

• Vote for the Breakthrough Award winner
• David Tennant back as Hamlet after back surgery
• Matt Smith is the new Dr Who