No 20th-century composer or conductor moved more naturally between musical worlds than Leonard Bernstein, and Mass, written for the opening of the Kennedy Centre in Washington in 1971, is his most spectacular attempt to unite those worlds in a single work. Lasting more than 100 minutes, this "theatre piece for singers, players and dancers" is exuberant, ambitious and likable; if it fails to meet its ambitions, it does so magnificently.
Everything about Mass is large-scale: this rare performance, conducted with such energy and care by Marin Alsop, involved the London Symphony Orchestra and its chorus, three children's choirs, a marching band from the junior department of the Guildhall School, a bevy of soloists and a (rather antique-sounding) four-channel tape. James Robinson had directed the staging, making maximum use of the Barbican's aisles and entrances to pin down Mass's hybrid nature, and contain its heady mixture of styles.
As the title signals, Mass is built around the Roman Catholic liturgy. But that only provided the skeleton: around it Bernstein assembled as a narrative thread a collage of texts (some of it rather awful) from a huge range of sources. The central character is the Celebrant (a spectacular performance of a demanding role by the baritone Jubilant Sykes), who loses his faith only to have it restored in a final coda, delivered by a boy treble (the enviably secure Edward Phillips).
The seismic shifts under way in American society when the score was written - the Vietnam war, the civil rights movement - provide the undercurrent and a reminder that there are no simple solutions, even though the piece hankers for one.
The score contains passages recalling Messiaen, Stravinsky, Britten and Berio alongside Bernstein's Broadway and blues and rock. There's no coherence, that's the point. It's uneven, too, though the best music is a reminder of what a great melodist Bernstein could be, never afraid of sentimentality.
Mass needs a performance that matches Bernstein's driving belief, which is what Alsop provided, so for a moment you could almost believe in its easy way out.
· To be broadcast on BBC Radio 3 next Sunday.
