# Jazz

A jazz loop at 120 to 170 BPM with swing 55 to 66: ride on every beat with
skip notes, a soft kick, a snare that comments rather than keeps time, a
walking acoustic bass in quarter notes, and comping on the offbeats with
sevenths. Use Acoustic (0) at lower volume or the base bank's Jazz kit (32), gm:33
Acoustic Bass, gm:1 piano or gm:5 electric piano, reverb send 2,500 to 3,000
on the piano, delay off. Harmony comes first here; the drums follow it.

## Skeleton

```compose
title Jazz skeleton
bpm 132
bars 4
key F major
genre jazz
swing 60

drums 32
name Brushes
vol 8000
ride:  x..o..x.o..o..x. | x..o..x.o..o..xo @78/96
kick:  x.......o....... | x............... @70/80
snare: ......o.......o. | ......o....o.... @60/72
phh:   ....x.......o... | ....x.......o... @62/74

bass gm:33
vol 8500
vel 96
G2@1>4 Bb2@5>4 D3@9>4 F2@13>4 | C3@1>4 E2@5>4 G2@9>4 Bb2@13>4 | F2@1>4 A2@5>4 C3@9>4 D3@13>4 | D2@1>4 F2@5>4 A2@9>4 C3@13>4

piano gm:1
vol 6500 rev 2800
G4+Bb4+D5+F5@2>3 G4+Bb4+D5+F5@7>2 G4+Bb4+D5+F5@11>4 | C5+E5+G5+Bb5@2>3 C5+E5+G5+Bb5@7>2 C5+E5+G5+Bb5@11>4 | F4+A4+C5+E5@2>3 F4+A4+C5+E5@7>2 F4+A4+C5+E5@11>4 | D4+F4+A4+C5@2>3 D4+F4+A4+C5@7>2 C5+F5+G5+Bb5@13>4
```

Templates: `progressions/jazz-ii-V-I`, `rhythm-changes-A`;
`bass/walking-quarters`. There is no jazz groove template; the skeleton's
drums are the starting point.

## Before and after

Before: `analyze` names the chords per bar (`Gm7 (ii)`, `Cdom7 (V)`,
`Fmaj7 (I)`, `Dm7 (vi)`) and the bass register `bass` up to D3, which is
above the C3 ceiling in bars 1 and 3. The rubric is a guide, and a walking
line that reaches D3 is idiomatic, so `lint` reports `bass-register` and you
keep it; nothing else fires.

```sh
soundfish humanize '<url>' trk_brushes --velocity 14 --seed 9 --operation op_brush
soundfish legato '<url>' trk_bass --operation op_walk
```

After: the ride and snare velocities spread, which is what a brushed kit
needs, and every bass note now lasts exactly until the next one, so the
walking line has no gaps. Do not `humanize` the piano; comping accents are
already written into the slots.

## Stage order

1. Harmony first: the progression in sevenths, comped on the offbeats,
   voiced above C4, one chord per bar or two.
2. Walking bass in quarters that lands on the root or fifth at each change.
3. Ride pattern with skip notes, then the kick and snare as comments.
4. Set swing by ear between 55 and 66; 60 is the default.
5. `humanize` the drums, `legato` the bass, `lint`, and keep the register
   finding when the line wants it.