By far the best-known and regarded piece of music composed by Allegri is the "Miserere mei, Deus", a setting of Vulgate Psalm 50 (= Psalm 51). It is written for two choirs, the one of five and the other of four voices, and has obtained considerable celebrity. One of the choirs sings a simple "fauxbordon" based on the original plainsong chant for the "Tonus peregrinus"; the other choir sings a similar "fauxbordon" with pre-existing elaborations and the use of cadenzas. The "Miserere" has for many years been sung annually during Holy Week in the Sistine Chapel. Many have cited this work as an example of the "stile antico" (old style) or "prima pratica" (first practice). However, its emphasis on polychoral techniques certainly put it out of the range of "prima pratica." A more accurate comparison would be to the works of Giovanni Gabrieli.