Composed 1913-16 and dedicated to Frederick Delius, The Warriors: Music to an Imaginary Ballet was originally composed for full orchestra. It is Grainger’s longest single work, nearly 20 minutes of sustained fantasy. “No definite program or plot underlies the music, though certain mind-pictures set it going,” the composer wrote. Grainger valued the clarity and transparency of sound in the pitched percussion, which he found particularly useful for what he called “double-chording,” a sort of panto...