In 1977, Samuel Beckett supplied the 16-line text for Morton Feldman's only opera, the monodrama Neither. Eight years later, Beckett suggested that the composer be asked to supply a new score for the writer's radio piece Words and Music, which had been broadcast by the BBC in the early 1960s but then withdrawn.

It was one of Feldman's last works - recorded in March 1987, six months before he died - and has become one of his most neglected. But a concert performance of Words and Music is the main work in the programme the Birmingham Contemporary Music Group, under Finnish conductor Susanna Malkki, is currently touring for the Arts Council's Contemporary Music Network.

Beckett's terse, unresolved power game between words and music is personified by the characters Joe and Croak, played by David Sibley and Clive Merrison. Their disembodied voices are projected over the ensemble via loudspeakers. The music is the third protagonist. Feldman's score may seem like a series of wisps and fragments - a few bars here, another phrase there - but it is always instantly identifiable as Feldman, and offers the extra dimension, the non-verbal realm, that Joe and Croak are unable to express. It is a gripping, teasing half-hour.

Two of Gerald Barry's ensemble pieces offer a 50th birthday tribute and provide sharp contrast to the Beckett/ Feldman work. Wiener Blut (which BCMG commissioned two years ago) and Bob (from 1989) have such energy and unvarnished emotional directness that the latest BCMG commission, from French composer Marc-André Dalbavie, seems redundant. Dalbavie's Palimpseste is such an anodyne piece - trickling scales for strings and piano, negligible antiphonal effects - that it seems unlikely to make much impact in any context.

At the Union Chapel, London, tomorrow. Box office: 0870 120 1349.