Guillaume Dufay – Nuper Rosarum Flores

This isorhythmic motet contains vocal lines in four varying metrical pattern that then create a metrical ratio of 6:4:3:2. While not all of the metrical shifts are noticeable to the ear, the relationships between the voices are striking and the oft-mentioned “architectural” style of this work is one that makes it worth hearing, especially when considering how meter, tempo, and accent affect listening.

Steve Reich – Piano Phase or Violin Phase

Written for piano or violin to play against itself, via pre-recorded tape, this work is one of the first to demonstrate phase shifting – a process by which the live player grows slowly out of sync with the tape. This creates innumerable metrical and beat layers, leading to a complex work where the melody is limited but the rhythmic possibilities abound.

Black Earth Ensemble – Oankali

This work of avant-garde jazz by Nicole Mitchell’s Black Earth Ensemble eschews traditional meter, but the rhythmic prodding of the acoustic percussion sets up beat groups or cells that are them improvised upon by the larger ensemble. Also the unusual accented punctuation of scat and nonsense sounds, moving to wails, creates a sense of plastic time – stretched and pliable – even as the percussion and eventually drum kit come in with portions of a unstated groove.