skills/ensemble-arranging/references/jazz-horns.md

# Jazz: combo horns and big band

## Roles

| Ensemble | Lead | Harmony | Bass | Comping | Time |
| --- | --- | --- | --- | --- | --- |
| trio | piano right hand | piano right hand | bass | piano left hand shells | drums |
| quartet, quintet | trumpet or tenor-sax | second horn in thirds/sixths or counter-line | bass | piano | drums |
| sextet, septet | trumpet | tenor-sax and trombone in block voicing | bass | piano (guitar optional) | drums |
| big band in 8 parts | trumpet ("Trumpet 1") | trumpet 2, alto-sax, tenor-sax, trombone | bass | piano | drums |

## Two horns

- Thirds or sixths below the lead for the A section, unison or octaves for
  the strongest statement, a counter-line (long notes moving against the
  melody) for the B section.
- Never a fourth or fifth for more than one beat unless both are chord tones.

## Three horns (trumpet, tenor, trombone)

- **Block voicing.** All three share the lead's rhythm. Under each lead note
  place the two nearest chord tones below it, within an octave, choosing so
  that the 3rd and 7th are present when the lead is neither. Trombone takes
  the bottom, tenor the middle.
- **Spread voicing** for long notes: trombone on the root or 3rd around
  C3 to G3, tenor on the 7th or 3rd, trumpet on the melody or a tension.
- **Alterations agree.** On a 7alt or 7b9 chord, the inner voices use b9,
  #9, #11, b13 and the 3rd and b7 only. On a plain 7 they use 9 and 13.
- **Lead ranges.** Trumpet melody in G3 to G5 sounding, peaks to Bb5. Tenor
  inner voice C3 to C5. Trombone bottom A2 to F4.

## Big band in eight parts

- Saxes: alto lead, tenor a chord tone below, the pair in thirds and
  sixths like a soli.
- Brass: trumpet 1 lead, trumpet 2 a chord tone below within a fifth,
  trombone on the guide tone that the saxes miss or the root of a spread.
- **Tutti**: everyone in block voicing on the shout chorus, whole band
  resting on the offbeat between punches.
- **Sax soli / brass punches**: saxes carry a phrase for two bars, brass
  answer with a two- or three-note punch on the offbeats, then rest.
- **Backgrounds behind a soloist**: long notes (half and whole) entering
  after the soloist's first bar, moving by step, never in the soloist's
  register.

## Voicing techniques

- **Four-way close**: lead plus the next three chord tones directly below,
  all within one octave.
- **Drop-2**: four-way close with the second voice from the top moved down
  an octave; the standard sax and brass sound.
- **Rootless piano voicings**: 3-5-7-9 or 7-9-3-5 (with 13 replacing 5 on
  dominants), right hand between C4 and A5, left hand a shell (root and 7th
  or 3rd and 7th) between C3 and C4 only when there is no bass.

## Rhythm section, medium swing

- **Bass**: walking quarters. Root on 1, chord tone on 2 and 3, approach
  note on 4 (a half step below or above the next root, or the 5th of the
  next chord). One octave leap per four bars at most. Register E1 to G3.
- **Piano**: comps in the gaps of the horns with three- or four-note
  rootless voicings, Charleston rhythm (dotted quarter, eighth) or hits on
  the and-of-2 and 4. Rests on most beats. Left hand doubles nothing the
  bass plays.
- **Drums**: ride on every quarter plus the skip note (an eighth on the
  and-of-2 and and-of-4), hi-hat pedal on 2 and 4, kick light on 1 of
  section starts only, snare comps sparse offbeats, crash on the first beat
  of a section. With `feel: swing` write the skip as straight eighths.
- Everyone lands the first beat of bar 1 and bar 5 together; between them
  the horns rest and the piano answers.

## Eight-bar head plan

| Bars | Horns | Piano | Bass, drums |
| --- | --- | --- | --- |
| 1-2 | phrase 1 in block voicing | one hit at the end of bar 2 | walk, ride |
| 3-4 | rest, or trombone holds a guide tone | fills the gap | walk, ride |
| 5-6 | phrase 1 varied, higher | one hit | walk, ride |
| 7-8 | cadence figure and a held last note | final voicing on the and-of-4 of bar 8 | fill in bar 8, crash on the last chord |