Ableton Humanize

Ableton Humanize

Make stiff, grid-locked MIDI feel played-by-a-human by reading an existing clip and rewriting its notes with micro-timing offsets, swing, and velocity dynamics. The "lazy" lofi feel and a tight funk pocket are both just controlled deviations from the grid.

When to use

Triggers: "humanize", "add swing/groove", "less robotic", "shape velocities". To generate new parts use the composition/groove skills; this one transforms an existing clip.

Process

1. Use ableton-live-runner for build/run/kill + scaffold.
2. Read the target clip's notes (clip.notes). Operate in place (rewrite the same clip) or write

a humanized copy — confirm which with the user.

1. Apply transformations (let the user pick intensity; keep it subtle by default):

• Timing jitter — nudge each note startTime by a small random offset (±0.005–0.02 beats).
• Swing — push notes on off-beat subdivisions later (8th swing: +0.04–0.08; 16th swing

smaller). Decide the subdivision from the note grid.

• Feel offset — a constant lean: drag the whole part slightly late (laid-back) or early (on

top). Drums often want snare-late, kick-on.

• Velocity dynamics — accent strong beats, soften off-beats/ghosts; add ±gentle variation;

optionally a slow swell across a phrase.

• Duration variation — vary note lengths slightly (legato vs staccato) for realism.

1. Clamp — keep startTime >= 0, velocities in 1–127, and don't let jitter create flams unless

wanted. Write the array back with clip.notes = newNotes.

Code pattern

const rand = (a) => (Math.random() * 2 - 1) * a;
function humanize(notes, { jitter = 0.012, swing = 0.06, velVar = 6, drag = 0 } = {}) {
  return notes.map(n => {
    const isOff = Math.round((n.startTime % 1) * 2) % 2 === 1; // on an 8th off-beat?
    return {
      ...n,
      startTime: Math.max(0, n.startTime + rand(jitter) + drag + (isOff ? swing : 0)),
      velocity: Math.max(1, Math.min(127, Math.round((n.velocity ?? 90) + rand(velVar)))),
    };
  });
}

Limits

• This shifts note events, not Ableton's Groove Pool (no groove-template API). For consistent swing

across many clips, consider baking the same offsets.

• Over-humanizing muddies tight genres — default to subtle, increase on request.

See ableton-drum-groove, ableton-topline.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: Korben00
• Source: Korben00/ableton-producer-skills
• License: MIT

Install and usage instructions live in the source repository linked above.