Polyrhythm

Time & Groove

Also called polyrhythms, cross-rhythm, 3 over 4, 4 over 3.

A polyrhythm is two rhythms played at once that do not divide evenly into each other. Three against four is the classic: one hand plays three evenly spaced notes in the same space where the other plays four. They start together, drift apart, and meet again at the top of the next cycle.

To feel it, use words. "Nice cup of tea", four syllables, against "cup of tea", three syllables, played together over a steady beat, is 4-over-3 against 3-over-4. Or clap four even notes while your metronome plays triplets. The two layers pulse against each other, then resolve. That is the whole effect.

You will hear polyrhythm in West African drumming, in Afro-Cuban music where a clave sits under triplet-based melodies, and in plenty of rock, where a shuffle pattern in one hand floats over straight notes in the other. On a drum kit, polyrhythm usually means one limb holds a pattern while another plays against it.

Tip: start with 3-against-4 between your hands on a pad, slowly. Right hand plays three, left plays four, both start on 1. Learn where the notes interlock: the second note of the threes lands just before the third of the fours, the third of the threes just after it. Say it first, then play it. Evenness comes before independence.