Isorhythmy

Isorhythmy (from the Greek ἴσος “equal” and ῥυθμός “measure of time”, roughly “same rhythmic order”), also called isorhythmics , is a design principle of the motet in the 14th and 15th centuries. The terms do not come from that time, but are modern names that were only coined by Friedrich Ludwig at the beginning of the 20th century .

In isorhythmy, a rhythmic structure is repeated in sections, whereby the pitches usually change. The repetitive rhythmic model is called Talea (from Old French taille "section"); it usually corresponds to the strophic form of the text. This model does not always have to be strictly adhered to in all parts; it occurs primarily in the cantus firmus parts , i.e. in the tenor and contratenor . The corresponding melodic section is the color (from the Latin color "color, tone"). Especially in the isorhythmic motet of the 14th and 15th centuries, which is considered the climax of the Ars nova , Taleae and Colores are not used congruently, but the melodic and rhythmic phases are shifted against each other and overlap. In the case of multi-part motets, diminutions and changes in the length of the upper part often appear in the final parts .

Isorhythmic movement in Guillaume de Machaut's Motet No. 9. In the tenor part, two colores and three taleae overlap.

The first beginnings were evident in Philippe de Vitry's work . This type of isorhythmy is particularly pronounced in Guillaume de Machaut's motets . In addition, isorhythmic structures can also be found in many song and mass compositions of the time. A forerunner of isorhythmy, in which the taleae are only repeated in the tenor part, is the isoperiod of the motet in the Ars antiqua . The other voices keep the same rhythmic periods as the tenor. In the 20th century, isorhythmy was used again by Anton Webern , Igor Stravinsky and Witold Lutosławski for some compositions. György Ligeti , too , based the compositional style of Lux aeterna on the “Talea technique”. In the field of jazz, the Swiss pianist Christoph Stiefel explicitly refers to this principle.

literature

• Friedrich Ludwig: The polyphonic music of the 14th century . In: Anthologies of the International Music Society, Vol. 4 (1902/03), pp. 16–69
• Jon Michael Allsen: Style and intertextuality in the isorhythmic motet 1400-1440 . (Dissertation) University of Wisconsin Press, Madison 1992
• Laurenz Lütteken : Guillaume Dufay and the isorhythmic motet. Genre tradition and work character on the threshold of modern times . (Dissertation) Wagner, Hamburg / Eisenach 1993, ISBN 3-88979-062-3

Individual evidence

1. ^ György Ligeti: Collected writings. Volume 2 . Ed .: Monika Lichtenfeld. Schott, Mainz a. a. 2007, ISBN 978-3-7957-0451-3 , pp. 234 ff .