MUSIC: Sweet Georgian brawn

BBC SO / John Nelson RFH, London

Sunday night is no time for surprises, but the BBC Symphony Orchestra brought two of them to the Royal Festival Hall: the UK premiere of Giya Kancheli's 1987 cantata Light Sorrow, and the harrowing contrast between its stark vision of childhood a nd the childhood innocence at the heart of Mahler's Fourth Symphony, given a lively reading by the American conductor John Nelson.

Kancheli himself already has a reputation here, albeit largely among CD-buyers. Georgian by origin, he is the author of music purveying a strange calm disrupted by awesome outbursts of terror. The instrumental language combines the violence of programmatic Shostakovich with the spiritual ambit of Gorecki. Some who find Schnittke overblown, or over-promoted, have offered Kancheli as a perfect antidote, mixing glimpses of the abyss with the serenity of Part or Tavener.

Light Sorrow proved typical of the composer. With Britten's War Requiem as a model, it blended texts from different sources - Shakespeare, Goethe and the Georgian poet Galaktion Tabidze - in a moving lament dedicated "to children, the victims of war". Two trebles, entering to the background of a prolonged organ note, were complemented by the voices of the New London Children's Choir, impeccably trained by Ronald Corp and arrayed both behind and within the orchestra.

As in Kancheli's seven symphonies, the music traversed the same landscape many times, though always from an individual perspective. There was an unmistakably personal presence in the sudden, ear-splitting climaxes and the grief-laden string lines in between, laced at one point with the cool sounds of harp and spinet. But it was the way of contrasting the two worlds that seemed most idiosyncratic, and most appropriate to a piece drenched in the sorrow of shattered childhood. Though time will prove the ultimate test of this idiom and of its power to rival either the ferocity of Schnittke or the calm of other "faith minimalists", Sunday's audience found its effect positive and immediate.

In Mahler's Fourth, too, the dream of innocence becomes, for a while, a nightmare. Butwhereas Kancheli conjures his vision from a few simple ideas, Mahler, as Deryck Cooke observed, offers "an endless supply of significant material". Nelson cut no corners in leading this flow to its concluding child's view of heaven, sung with warmth and purity by soprano Sylvia McNair. Refined woodwinds gave vivid reality to the first movement; and, while the Scherzo flagged, Nelson's strong, alert phrasing gave an added purpose to the sublime Adagio, with nothing overstated, every note in its proper place.