AI Generation

The Generation tab lets Sigil compose MIDI for your tracks. It can create new material, fill empty target ranges, or continue from existing musical context.

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Generation modes

Mode	Use it for
Generate	Create new content from scratch for selected tracks and bars.
Fill Track	Generate only into empty target ranges while preserving existing notes.
Continue	Read an existing context range and append new bars after it.

Use Generate for first sketches, Fill Track for missing parts, and Continue when extending an existing section.

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Conditioning

Control	Purpose
Genre	Choose a trained genre tag, or leave on Any.
Mood	Choose a trained mood tag, or leave on Any.
Genre strength	Controls how strongly genre steers output.
Mood strength	Controls how strongly mood steers output.

Project tempo, meter, instrument setup, track names, and existing MIDI context also guide the result.

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Targeting

The track checklist controls which tracks the model writes into.

• Ticked tracks receive generated notes.
• Unticked tracks can still provide musical context if they contain notes.
• For Fill Track, target ranges must be empty on the target track.

Advanced polyphony and note-length controls shape melodic density. Infill density is especially important for drums.

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Length and candidates

• Target bars sets how many bars to generate.
• Context bar selects the source range for Continue mode.
• New bars sets how much fresh material Continue mode appends.
• Candidates generates multiple alternatives so you can audition and choose the best result.

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Sampling parameters

Setting	Effect
Temperature	Higher values are more varied; lower values are more conservative.
Max new tokens	Generation budget for newly written material.
Top-k	Restricts choices to the K most likely next tokens.
Top-p	Uses nucleus sampling; lower values reduce variety.
Repetition penalty	Discourages looping or repeated token patterns.
Infill density	Controls density for native infill, strongest on drums.
Polyphony limit	Caps harmonic thickness.
Min / Max polyphony	Controls melodic arrangement density.
Min / Max note length	Controls duration bands.
Infill span	Controls how many bars native infill rewrites at once.
Seed	Reproducibility value. Lock it to repeat a run.

Start near temperature 0.9, then adjust after listening.

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Generation history

Every generation run is saved to history with a preview audio file and setup details.

Use History to:

• Audition previous results.
• Import an earlier result into the current project.
• Compare different settings.
• Recover a result you liked but did not apply.

Import can replace source bars or create new tracks, and restores the saved timing/key snapshot before applying notes.

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Candidate picker

When Candidates is greater than 1, Sigil opens a picker after generation.

Audition each candidate, select the strongest result, and apply it. If none work, close the picker, adjust settings, and generate again.

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Better results

• Pick genre and mood tags that match the target style.
• Keep first generations short, usually 4-8 bars.
• Use Continue mode to extend ideas instead of generating a whole song at once.
• Add at least one existing track or pattern to provide context.
• Increase repetition penalty slightly if output loops too much.
• Lower temperature if output becomes chaotic.
• Always review and clean up generated notes manually.