The premiere performance of Polymora by the Eastman Percussion Ensemble, Michael Burritt, conductor

Polymora (2019)
for
percussion ensemble

by
Robert Morris

Program Notes

Polymora is my first composition for percussion ensemble.(not counting Stream Runner (2007) for Marimba with optional percussion quartet). I wrote the piece at the request of Michael Burritt, the director of the Eastman Percussion Ensemble. The composition is based on Carnatic (South Indian) rhythmic concepts especially focusing on tala and mora. A tala is a rhythmic cycle (akin to, but not equivalent to the western concept of measure or meter). A mora is a rhythmic pattern iterated three times ending just before or on a specified beat in a tala. Moras may be of any size from a rhythmic cell to a long complex series of embedded moras (sometimes called a korvai). The composition is written in the tala misra capu, a seven beat cycle divided 3, 2, 2. The rhythmic patterns are completely made out of simultaneous and successively unfolding moras; hence the piece’s title.

For the pitch materials in Polymora, I borrowed five Indian-derived pentatonic scales. These are not ragas, just scales, but they have names in Indian music theory. The names and notes of the scales are given below; the last three are rather rare, not used in current practice, but are listed in Indian treatises.

Polymora is scored for vibraphone, marimba, harp, piano, four high drums (bongos) four mid-range drums (tomtoms), four low drums (timbales), and tubular bells. The drums are played with the hands.