"Requiem" (1963–65) is a work for soprano and mezzo-soprano soloists, twenty-part chorus (four each of soprano, mezzo-soprano, alto, tenor, and bass), and orchestra. Though, at about half an hour, it is the longest piece he had composed up to that point, Ligeti sets only about half of the Requiem's traditional text: the "Introitus", the "Kyrie" (a completely chromatic quasi-fugue, where the parts are a montage of melismatic, skipping micropolyphony), and the "Dies irae"—dividing the latter sequence into two parts, "De die judicii" and "Lacrimosa".