The American countertenor Christopher Lowrey founded the vocal ensemble Altera ‘to form the beating heart of professional choral music in the United States’. Now regarded as one of the finest and most enterprising choirs on the North American continent, Altera's programme includes timeless works by Gibbons, Lotti, Scheidt and Bruckner, as well as twentieth-century compositions by Poulenc, Messiaen and others. Barber’s celebrated Adagio sits alongside the moving Salvator Mundi, taken from Herbert Howells’s Requiem. Not forgetting three world premiere recordings of works written or arranged for Altera by composers Joanna Marsh, Zuzanna Koziej, and Michael Garrepy, who has arranged Were you there?