Poliritmia

Poliritmia is a musical concept describing the simultaneous use of two or more independent rhythmic streams within a piece. The term derives from Greek roots poly- (“many”) and rhythmos (“rhythm”). In practice, poliritmia creates a textured surface in which different voices or instruments emphasize different pulse groups or subdivisions, producing a larger rhythmic organization than any single line would alone. It is related to, but distinct from, hemiola (a temporary shift in metric accents, often 3 against 2) and cross-rhythm (the interaction of two or more conflicting meters).

Common examples include two patterns played in the same span but with different subdivisions, such as 3:2 or 4:3, or more complex layers like 5:4 or 7:6. In African drumming, interlocking ensembles often generate interwoven poliritmic textures. In Western classical and contemporary music, composers use poliritmia to create rhythmic color and drive; examples appear in the work of Stravinsky, Olivier Messiaen, and Steve Reich. In jazz and fusion, players employ polyrhythms between hands or within comping patterns.

Performance and notation: poliritmia is notated with separate rhythmic voices on multiple staff lines or with percussion notation that indicates independent parts. In ensembles, musicians align their patterns at a common multiple of the subdivisions; practicing with metronomes or subdivision drills helps internalize the relationships. Analysts study poliritmia to understand how layered rhythms interact and shape groove, structure, and motion in a piece. See also polyrhythm, hemiola, cross-rhythm.