POP / Sound tracks: Ryuichi Sakamoto - Edinburgh Playhouse

You never quite know what to expect from Ryuichi Sakamoto. Here is a man who will jump from composing for Bertolucci to recording with Iggy Pop. One minute he's arranging and conducting the music for the opening ceremony of the Olympics; then it's off to the studio with John Lydon. Live, he can be just as unpredictable.

With Yellow Magic Orchestra he would take to the stage in glasses and grey suit, a camera slung from his neck just like any other good Japanese tourist. In 1985, he performed TV WAR, a sci-fi spectacular incorporating video and computer graphics. So it came as no surprise when Japan's premier pop musician ambled on to a minimalist set at the Edinburgh Playhouse with just a cellist and violinist for company.

'I'm a little bit nervous,' he wavered. 'It's my first time in Edinburgh . . . (long, nervous pause) Er, nice to see you, all of you, thank you for coming.' Was the legendary techno-wizard sending up the traditional Western rocker's greeting of 'Hello Edinburgh'? Not a bit of it. He genuinely was suffering from an attack of nerves, the sweetie-pie, and spent the entire concert dropping things and forgetting names. At one point he even broke off mid- ramble, startled by a smoke machine. This, of course, only served to compound audience adulation. By the second number, the brooding theme from Almodovar's High Heels, they were entranced.

Sakamoto's best work is tinged with melancholy, none more so than the dark, slightly menacing score from Sheltering Sky. 'After I finished that,' he told us, barely suppressing the luvvie in him, 'I was so sad I couldn't do anything for six months . . . except watch CNN.' After the Oscar-winning theme from The Last Emperor, a gorgeous sweep of grand piano threaded through with oriental strings, came what he likes to call his 'pop pieces', which are, in fact, jazz-based. Take his composition about cats: a complex yet delicate arrangement packed with surprise turns, including a miaowing violin.

He then found himself in the unusual position of needing to plug his new CD, Sweet Revenge, yet being unable to dip into it since all but one of the tracks utilise guest singers. As he opened his larynx, the reason for the use of voices other than his own quickly became apparent. Sakamoto suffers from what you might call vulnerable vocals. This is a man who will spend up to 20 months in the recording studio perfecting his music, yet he can hardly hit a note. Nor is lyric honing his forte: 'Though I wish I could stay / I must be on my way / Say goodbye now / Don't cry now'.

Then, after 70 mostly exquisite minutes, he completed the recital with a beautiful rendition of his greatest hit, 'Merry Christmas, Mr Lawrence'. It had been a night of flawed genius.