Gregorio Allegri was an Italian composer of the Roman School and brother of Domenico Allegri, also a composer of note. As a benefice in the cathedral of Fermo, Allegri composed a large number of motets and other sacred music, which, being brought to the notice of Pope Urban VIII, obtained for him an appointment in the choir of the Sistine Chapel at Rome as a contralto. He held this from 1629 until his death.
Among Allegri’s musical compositions were two volumes of concerti for five voices published in 1618 and 1619; two volumes of motets for six voices published in 1621; an edition of a four-part sinfonia; five masses; two settings of the Lamentations of Jeremiah; and numerous motets which were not published in his lifetime. He was one of the earliest composers for stringed instruments. Most of Allegri’s published music, especially the instrumental music, is in the progressive early Baroque concertato style. However, his work for the Sistine Chapel is descended from the Palestrina style, and in some cases strips even this refined, simple style of all ornament. He is credited with the earliest string quartet.
By far the most well known and regarded piece of music composed by Allegri is the Miserere mei, Deus, a setting of Vulgate Psalm 50. 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 constant use of the dominant seventh chord and 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.
The Miserere is one of the most often-recorded examples of late Renaissance music, although it was actually written during the chronological confines of the Baroque era; in this regard it is representative of the music of the Roman School of composers, who were stylistically conservative. He lived from 1582 to February 17, 1652. —Excerpted from Wikipedia