Stephen Layton has come up with a most attractive programme of a cappella choral pieces by twentieth century American composers.

I think it's fitting that there's a substantial focus on Samuel Barber for he was arguably the best American writer for voices of his generation. Agnus Dei is his own arrangement of the slow movement from his String Quartet, which acquired even greater celebrity when he arranged it for string orchestra. I prefer the string orchestra version to the choral arrangement—only the strings, I think, can do the fullest possible justice to Barber's long and often very high-lying cantabile lines. However, this Polyphony performance is as fine an advertisement for the choral version as I've heard. Layton achieves an exemplary blend—the right vocal line always seems to achieve the correct degree of prominence at just the right moment. The climax, when it arrives, is marvellously intense.

The three short pieces that comprise Reincarnations demonstrate just how good Barber was at writing for the human voice. The excitement of love is superbly conveyed by both the composer and these performers in 'Mary Hynes'. Polyphony bring out the grief of 'Anthony O'Daly' and they're equally successful with the gently lilting rapture of Barber's music in 'The coolin''. Later in the programme I was very taken with A nun takes the veil. This is Barber's own arrangement of one of his Op 13 songs. The song is a fine one in its original form but this choral re-imagining works just as well. The Emily Dickinson setting, Let down the bars, O death was chosen by Barber to be sung at his own funeral. It's an eloquent piece and here it gets a very intense performance. A couple of years ago I reviewed a Barber disc by the excellent American choral ensemble, Conspirare. That included several of the pieces that Stephen Layton presents here. The Conspirare performances were very fine but these by Polyphony are at least as good. Happily for Barber devotees, the respective programmes complement each other so duplication of a few items is fully justified.

The disc begins and ends with music by Randall Thompson. His Alleluia is very familiar; indeed, it's his best known work. I didn't know—or had forgotten—that Koussevitzky commissioned it as a choral fanfare to mark the opening of Tanglewood in July 1940. However, as Meurig Bowen relates in his notes, Thompson was greatly troubled by events in wartime Europe and felt unable to supply a celebratory piece. Bowen points out, justly, that though Thompson's idiom is conservative we can now look back and, arguably, regard the piece as ahead of its time in that the likes of Tavener and Lauridsen have trodden a similar path. The present performance benefits from flawless and expertly controlled singing. Stephen Layton builds the tension slowly and patiently to the climax. This is a splendid performance.

Much less familiar is Fare Well, a Walter de la Mare setting that Thompson composed for a memorial service. The piece is as touching as it is beautiful. The music may be conservative in idiom but, frankly, who cares? Stephen Layton is even more expansive than is James Burton in his very fine Hyperion disc devoted to Thompson's choral music (review). Burton and the Schola Cantorum of Oxford take 8:23 against Layton's 9:19. Polyphony's rapt performance is a wonderful conclusion to the programme.

Very different from these Thompson pieces is Bernstein's Missa brevis. This has its origins—and again I'm indebted to Meurig Bowen's notes—in some incidental choral music that Bernstein wrote in 1955 for The Lark, a play about Joan of Arc. The celebrated American conductor, Robert Shaw suggested that the music could be re-worked into a Mass setting. However, it was not until 1988 that Bernstein got round to following up this idea when he produced the Missa brevis to mark Shaw's retirement as Music Director of the Atlanta Symphony Orchestra and Chorus. It's a fascinating piece, cast in six short movements—actually, the fifth and sixth, though separate movements, form the Agnus Dei. The scoring is for mixed chorus and there's a prominent part for a countertenor solo, here expertly sung by David Alsopp. There's also an important contribution from a percussion player—here Robert Millett—who plays tubular bells, tam-tam and bongos at various times. Bernstein is tactful in his use of percussion so that each time this resource is deployed it really makes a difference. Stephen Layton and his choir give a committed, vibrant performance of this work and I enjoyed it very much.

Aaron Copland's Four Motets date from the time of his studies with Nadia Boulanger and, indeed, he wrote them as a compositional exercise for her. They lay unpublished for a long time but are well worth hearing. The first, Help us, O Lord is fluent and mostly gentle in nature. Thou, O Jehovah, abideth for ever is a forthright setting and there were times when I wondered if Copland might have had at the back of his mind the religious pieces written by New England composers such as William Billings. Have mercy on us, O my Lord is expressive and features some particularly impressive writing while the brief Sing ye praises to our King rounds off the set in boisterous style.

The music on this programme is consistently interesting and everything is performed with the consummate skill that one has come to associate with Stephen Layton and Polyphony. The sessions were spread over quite a period of time but the recorded sound seems pretty consistent to me: the team of producer Adrian Peacock and engineer David Hinitt have produced very pleasing sound. Meurig Bowen's notes are excellent.