MUSIC / Dressed to impress: Robert Maycock on Jessye Norman's gala performance with the London Symphony Orchestra at the Barbican Hall

Whoever called this gala concert 'Jessye Norman - Impressions' had the wrong idea about its impact. Nothing could be less vague, qualified, impressionistic. Impressive, on the other hand, is an understatement.

If you were expecting the usual kind of gala, something like Dame Kiri's 50th birthday, you were on the wrong planet. But then Norman isn't your usual star singer. You won't find her singing for the World Cup; a solo 'Marseillaise' in the Place de la Concorde is more her style, though her true element is the straight concert performance of an extended, serious work. The grand entry, the imposing presence, the resplendent orchestra, all are there, but at the centre it is one- to-one communication with that voice and those looks, a wholly musical experience of dramatic intensity and surprising intimacy.

Monday's was a solid programme of Benjamin Britten and Richard Strauss, to suit the solid fund-raising cause of the LSO's Endowment Trust, which provides for the orchestra's commissions of new pieces and its forays into musical education.

Sir Colin Davis, principal conductor elect, ensured the occasion kept its gravitas. The intriguing choice in the programme was Britten's cantata Phaedra, written at the end of his life for Dame Janet Baker and inevitably associated with vocal Englishness, a blend of the plaintive and the hard- edged born out of Handel opera and Shakespearian theatrical tradition.

Norman relished as far as she could its depiction of the dying queen spurned by the gorgeous youth; nothing wan or forlorn, all lyrical focus and direct emotion. It's a strange, cramped piece in comparison with Britten's finest operas. There is little any singer can do about the arid accompaniment for small orchestra, with its rattling harpsichord and shudders of drums, and Norman left a disconcerting sense of being too generous for it, of not being fully stretched.

What had packed the audience in was the chance to hear her sing the closing scene of Strauss's opera Capriccio, the outpouring of gentle erotic feeling in which the Countess, with a smile, fails to choose between her two lovers, who symbolise the priority of words or music in the making of opera itself. This was a fine match of composer's and singer's artistry. The old wizard's understanding of the female voice was rewarded in long spans of phrasing, unstinted tonal richness, and the reserves of physical power and musical concentration that could prepare the scene's distantly signalled peaks and climaxes, leading rather than following the subtleties of the vocal line as it headed now away, now around, finally straight for home.

Even this, though, was not the evening's only high point. You expect galas to be padded out with orchestral items while the singer rests. But here, with Britten's 'Sea Interludes' from Peter Grimes and Strauss's Don Juan, what the orchestra played alone was altogether greater music.

What's more, everything the LSO does with Davis right now seems to exist in a dimension of its own. In the Grimes pieces, they brought out sustained dark undercurrents as strongly as the sound and fury, a Sibelius-like experience of the vast and slow-moving simultaneously with the frantic and local.

A headlong Don Juan had room for expansive, full-hearted melody from horns and violins at the same time as it brought an improbable precision to the details in the string textures that usually sound a bit of a scramble. All this, and Davis is still only a guest conductor until the September after next. It's an inspiring prospect.

A further performance (at non-gala prices), takes place on Thursday, 7.30pm, at the Barbican Hall, London EC2

Haydn and Berlioz programme, 21 March, 7.30pm