The roles
- Drums: tempo and form. Fills at the end of sections, crash on the 1 of new ones, pattern changes for verse/chorus.
- Bass: root and movement, locking with the kick, passing notes toward the next chord. Typical register E1–G3.
- Keyboards: comping, pads, riffs. Voicings between C3 and C5 to avoid muddiness; the left hand does not double the bass.
- Guitars: strumming, arpeggios, single-note riffs, muted chords, power chords. High inversions to leave room for the bass.
Principles
- Register allocation: each instrument has its own space in frequency.
- Rhythmic interlocking: if one plays straight eighth notes, the other plays offbeats; if the guitar is dense, the piano holds.
- Density curve: light verse, full chorus, different bridge.
- Adapting the lead sheet: anticipations (chords arriving an eighth note early), delays, rhythmic augmentation and diminution.
Example in C (C – G – Am – F)
- Verse: kick on 1 and 3, bass in whole notes C G A F, piano with sustained chords in inversion (C – G/B – Am – F/A).
- Chorus: bass in eighth notes, guitar in muted eighth notes with an accent on the offbeat, piano with octave stabs on the melody, open hi-hat on the offbeats.
- Bridge: half-time drums, bass on long notes, arpeggiated piano.
Real-world example
“Superstition” by Stevie Wonder (1972): several interlocking clavinet parts, a synth bass, drums and horns. Each part on its own is simple; together they form a very tight groove. It is a model of rhythm-section arranging.