Wikipedia about: 'Miserere mei, Deus' by Gregorio Allegri

Miserere by Gregorio Allegri (also called "Miserere mei, Deus") is a setting of Psalm 51 (50) composed during the reign of Pope Urban VIII, probably during the 1630s, for use in the Sistine Chapel during matins on Wednesday and Friday of Holy Week. It was the last of twelve falsobordone Miserere settings composed and chanted at the service since 1514 and the most popular: at some point, it became forbidden to transcribe the music and it was only allowed to be performed at those particular services, adding to the mystery surrounding it. Writing it down or performing it elsewhere was punishable by excommunication. The setting that escaped from the Vatican is actually a conflation of verses set by Gregorio Allegri around 1638 and Tommaso Bai (1650 - 1718, also spelled "Baj") in 1714.

The Miserere is written for two choirs, one of five and one of four voices. One of the choirs sings a simple version of the original Miserere chant; the other, spatially separated, sings an ornamented "commentary" on this. Many have cited this work as an example of the stile antico or prima pratica. 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.

Although there were a handful of supposed transcriptions in various royal courts in Europe, none of them succeeded in capturing the beauty of the Miserere as performed annually in the Sistine Chapel. According to the popular story (backed up by family letters), the fourteen-year-old Mozart was visiting Rome, when he first heard the piece during the Wednesday service. Later that day, he wrote it down entirely from memory, returning to the Chapel that Friday to make minor corrections. Some time during his travels, he met the British historian Dr Charles Burney, who obtained the piece from him and took it to London, where it was published in 1771. Once published, the ban was lifted and Allegri's Miserere has since become one of the most popular a cappella choral works now performed. The work was also transcribed by Felix Mendelssohn in 1831 and Franz Liszt, and various other 18th and 19th century sources survive.

Mozart was summoned to Rome by the Pope, only instead of excommunicating the boy the Pope showered praises on him for his feat of musical genius.

Burney's edition did not include the ornamentation or "imbellimenti" that made the work famous. The original ornamentations were Renaissance techniques that preceded the composition itself, and it was these techniques that were closely guarded by the Vatican. Few written sources (not even Burney's) showed the ornamentation, and it was this that created the legend of the work's mystery. However, the Roman priest Pietro Alfieri published in 1840 an edition with the intent of preserving the performance practice of the Sistine choir in the Allegri and Bai compositions, including ornamentation.

The piece as it is sung today, with a high treble C, is inauthentic, and is the result of an error in the first edition of Grove's Dictionary of Music of 1880, in an article on ornamentation by the musicologist William Smith Rockstro. In it, he wrote out the first half of the verse twice, but transposed the second half up a fourth (as recorded in Felix Mendelssohn's transription). As a result the bass part leaps from F sharp to C, a progression (known as a tritone) and forbidden by the rules of counterpoint at the time when Allegri was working. Sir Ivor Atkins, then choirmaster of Worcester Cathedral, copied the Rockstro verse from Grove's for his English language edition of 1951, and liked what he heard.

Authentic editions have been produced in the last few years using Alfieri's account of 1840, original Vatican source material and other manuscripts, but most modern listeners know only the garbled 20th century version which remains highly popular with conductors.

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.

Over the years many visitors to the Vatican during Holy Week have been disappointed if there was not an Allegri Service on their day. The Miserere is regularly performed on Ash Wednesday in English cathedrals.

Arguably the most famous recording of Allegri's Miserere was that made in March 1963 by the all-male Choir of King's College, Cambridge, conducted by Sir David Willcocks, which featured the then-treble Roy Goodman. (This recording of the Miserere was originally part of an LP recording entitled "Evensong for Ash Wednesday"). The Tallis Scholars are an example of a group which uses a female soprano for the high solo.