BOBBY McFERRIN IN CONCERT

Music BOBBY McFERRIN IN CONCERT Royal Festival Hall, London

What happens when the world's most famous voice-as-instrument performer gets a whole orchestra of 65 real instruments to play with? Well, the orchestra get to sing for a start, or at least to hum along, on a rollicking instrument-free version of the William Tell overture. They also get to spend most of the evening with nothing to do. As McFerrin went through countless clever-clever routines, turning the London Phil into an Ernie to his Eric, you began to understand why, when you see Sir Edward Heath or Dudley Moore conducting on TV, their orchestras are so compliant, so ready to laugh out loud at the maestro's jokes, no matter how bad. They're getting paid. Even better, they've got very little to do for it.

Still, on Sunday night, the LPO was manfully up to the job and the players genuinely seemed to be enjoying themselves. When Bobby conducted them through the four movements of Mendelssohn's Fourth Symphony, it could have been a disembodied oven-glove holding the baton for all the notice they took of it, yet they dispatched the score with great elan. Indeed, you might almost think they could play it in their sleep.

This isn't to do McFerrin down, for he had the house in the grip of his oven-glove from the start. If audience-participation routines are usually cringingly embarrassing, McFerrin at least offers a winning persona in the Butlins Redcoat role, and the audience did him proud. As he pretended the front-of-stage was an enormous keyboard and instructed us to echo his lateral movements across the keys, almost everyone joined in, some with voices that could have graced the stage on their own.

The concept - high and low - comes from McFerrin's new album Paper Music, on which he adds vocal lines to well-worn classic themes. As a conceit, it seems wildly indulgent, but McFerrin at least has the vocal chops to carry it off. He is, as well as the body-resonating sound of television chocolate ads, the beautiful voice on the title track to the film Round Midnight, and he really can amaze with the eerie, Theremin-like tone of his vocalising.

In one of the many moments when the orchestra just sat back and watched, he delivered an a cappella ditty in which the percussive pulse was made by beating his chest, while an accompanying bass-line came from the microphone pressed into his cheekbone, as he added first one, then two, then three, sub-vocal melody and harmony lines. This was far more than a human beat- box and you could sense, behind the orchestra's eyeball-rolling bonhomie, real admiration.

When, for the encore, McFerrin cooed like a bird above a sweeter-than- sugar orchestral theme, the potential of the whole thing came alive; he really does sing like an angel and, with a voice like that, he should be able to do anything he likes. Too many Boston Pops, however, have taken their toll, preventing the performance from being entirely convincing. He should, you think, be improvising on Messiaen.

n `Paper Music' is on Sony CD and cassette