2. Polyrhythms

Polyrhythms occur when two or more different subdivisions share a common start (same downbeat) but divide time differently. Example: 3 evenly‑spaced notes against 2 in the same span (3:2). Unlike polymeter (different bar lengths), polyrhythm layers contrasting grids within the same bar.

Common ratios and feel

  • 3:2 (hemiola): classic cross‑rhythm; strong, danceable push–pull.
  • 4:3: four against three; feels slightly denser and more mechanical.
  • 5:4, 5:3, 7:4: odd‑over‑even patterns add tension and a modern/IDM edge.
  • Quintuplets/septuplets: exotic note groupings for more experimental textures.

Programming in a DAW (e.g., Bitwig/Ableton)

  • Use independent grid subdivisions: program one part on triplets and another on straight values.
  • Align the first hit of each layer; let patterns complete over the bar length.
  • Use different note lengths/velocities per layer to improve separation.
  • Modulation approach: cross‑modulate LFOs with different step counts (e.g., 5‑step vs 4‑step) to imprint polyrhythmic movement on filters, pitch, or amplitude.
  • Humanize selectively: add slight swing or micro‑delays to one layer to enhance the tug‑of‑war.

Musical impact

  • Built‑in tension/release as the layers drift and realign.
  • Clearer with contrasting timbres: bell vs. bass, pluck vs. pad.
  • Works great over a steady 4/4 kick to keep footing while adding complexity.

Tips

  • Start simple (3:2) and add one odd layer at a time.
  • Let one layer carry melody and the other act percussive to avoid clutter.
  • For aggressive grooves, quantize one layer tight and leave the other slightly loose.

Examples (16-step)

  • The widget lets you set any ratio (numerator vs denominator) and independently rotate each layer to test different downbeats. The primary voice maps to the blue buttons; the secondary voice uses amber buttons so you can hear/see their interlock.