Deller-Consort - Musique en France
Members of Collegium Aureum on historic instruments
Directed by Alfred Deller
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The name of Perotin and the musical significance of Notre-Dame have only come down to us indirectly, for until the mid-14th century, music manuscripts never contained the name of a composer. The great bishop Odo de Sully makes reference in his decrees to three and four-part organa. Nowadays the only two surviving organa quadrupla of Anonymous IV are recognized as works by Perotinus Magnus: the Gradual Viderunt omnes fines terrae for Christmas Day and the Gradual Sedenmt principes for St. Stephen's Day.
In the two powerful four-part works, the external form is provided by the alternation of polyphony and monophonic Gregorian chant. The great structure of the polyphonic sections derives from the alternation of organum and discantus. While the upper voices over the organum points are put together with consummate skill out of sequences, canons, techniques of voice alternation and varied motifs, the discantus sections are characterized by a stricter rhythmic structure in the cantus firmus. This kind of structure becomes a repeating rhythmic scheme in the Mors clausula - presumably also by Perotin: the chorale melody is structured by an extra-musical idea. Here is the beginning of the skilfully constructed isorhythmic motet of the 13th and 14th centuries - a structure which has still to reveal all its architectonic secrets.
Mathematical structures and intellectual forms determined the shape of the important musical forms, the isorhythmic motet and the mass, insofar as their structures lent themselves to rhythmic play of this kind. In the 14th century, Philippe de Vitry and Guillaume de Machaut became the finest exponents of this esoteric art. The Messe de Nostre Dame is the only liturgical music Machaut wrote. Alongside the Tournai Mass, on which a number of unknown hands worked, it is the only polyphonic setting of the Ordinary, the fixed components of the mass, before 1430. Two points strike the listener immediately. Machaut's harmonic language sets sound boldly against one another, producing an almost impressionistic effect. To this harmonic structure, Machaut adds an expressive melodic line. At the opposite end of the scale to this cantabile line is his especially striking use of rhythmically complex hocket technique. The upper voices are broken up by brief rests, usually so that they move sharply against each other.
A third characteristic of Machaut is the isorhythm, which inaudibly determines the structure of nearly all the motets. This Composition technique is based on a complex rhythmic scheme, applied first of all to the tenor, and then to the contratenor and parts of the upper voices as well. The text of the motets is also structured in such a scheme determined by extra-musical considerations. All these characteristics of Machaut's style are found in the parts of the Mass which are modelled on the motet: Kyrie. Sanctus.
Agnus Dei and Ite missa est. Gregorian plainsongs, taken out of their original musical contexts, are given to the tenor. Isorhythmically structured, they form the basis of the composition on which the upper voices, with their expressive melodies and hocketing, are built. In comparison with the complicated isorhythmic structures of the other parts, the style of the Gloria and the Credo, both of which have relatively long texts, seems old-fashioned; the homophony is completely determined by the text in a scansion which follows its natural rhythms. In both sections, only the words "Jesu Christe" and "Maria virgine" are singled out as islands of peace by virtue of their long note-values. Both final Amens end in extended exultant melismas.