Classical music
Schumann Revealed

The Barbican Centre, London

Peter Cropper, leader of the Lindsay Quartet, has described Haydn as "the most neglected of all the great composers". It's a usefully provocative label. But is Haydn uniquely neglected? Surely Robert Schumann could run him close. Sunday's final instalment of John Eliot Gardiner's "" weekend contained two concerts, both full of wonderful music, in which only one work - the Piano Quintet - could truly be described as core repertoire. Well, yes, inquisitive viola-players (they do exist) do sometimes try out the Marchenbilder ("Fairy-tale pictures") for viola and piano. But it's hard to remember any London performances of the G minor Piano Trio in recent years, and as for the choral and theatre pieces in the main evening concert, it is simply astonishing to see them done at all.

Why the neglect? Two received opinions get in the way. First, we are told that Schumann, a natural when it came to Lieder and solo piano works, was a very big fish out of water when it came to anything else. His orchestration is erratic, his choral writing unadventurous and his handling of large forms precarious. Second, there's his failing mental health and final mental collapse: the later works are intermittently inspired, but more often obsessive, repetitive - evidence of a mind in decline. Arguments like that have been used to damn the G minor Piano Trio. But Sunday's performance, by Daniel Phillips (violin), Steven Isserlis (cello) and Robert Levin (19th-century piano), revealed it as impassioned, unpredictable and almost shamefully tuneful. The Barbican Hall isn't the ideal location for chamber music: from the centre of the stalls it can sound as if the performance is taking place in an adjoining room. But the Piano Trio came across directly, with plenty of fire in its belly, as if the music were indignant on its composer's behalf. The Piano Quintet too was glorious - but no surprise there.

The evening concert, by the Monteverdi Choir, Hannover Boys' Choir and Orchestre Revolutionaire et Romantique, was one long surprise, even to those of us who thought we knew some of this music. Nachtlied ("Song of the Night"), a setting of a short mystical poem by Friedrich Hebbel, has moments like a Caspar David Friedrich nightscape realised in sound. Requiem for Mignon is deeply touching, not least in its writing for boys - sweet, but never cloying; its humanistic "return to life" ending is more effective than the Goethe-derived text would lead one to expect.

Even shorn of its theatrical context, the Manfred music is strangely effective, especially the Overture, one of the great pre-Lisztian symphonic poems (who says Schumann couldn't orchestrate?). As for the Final Scene from Goethe's Faust, this is, of course, far less spectacular than Mahler's setting in the Second Part of his Eighth Symphony, but Schumann makes sure you hear the words and follow Goethe's meanings. And even Mahler doesn't quite rise to Schumann's level in Doctor Marianus's ecstatic hymn - sung ecstatically here by baritone William Dazeley.

Thank providence for John Eliot Gardiner, one of those few conductors whom stardom has made more - not less - adventurous. He directed this music as though his interpretations had been ripening for years; too often such rarities get one run-through before they're pushed out on to the stage and effectively left to fend for themselves. Thanks above all to him, Schumann was indeed "revealed".

Stephen Johnson