Choose the harmony
Pick a Chord chain preset, type a progression in Manual chords, or use Random chords.
For jazz musicians & learners
Explore melody, rhythm, and jazz harmony
Jazz Improviser is a practical tool for jazz and blues musicians, students, and composers. Create melodic ideas over chord progressions, shape phrases with contours and motifs, and explore new variations in the piano roll.
About the app
Jazz Improviser helps you discover new melodic ideas over jazz and blues harmony. Choose from ready-made chord chains, write a progression yourself, or let the app create a random harmonic sequence. Adjust key, length, tempo, swing, and melodic character, then listen to the result right away.
The piano roll shows the melody over time. The blue contour guides overall pitch direction and register; the orange contour guides rhythmic density and note lengths. You can draw contours directly on the screen and generate a new version whenever you like.
The app is intended for improvisation practice, compositional sketches, and exploring harmony. Generated material is a starting point—the final musical judgment and development remain yours.
Harmony models are built from jazz research datasets, including the Weimar Jazz Database. Generated melodies are new statistical outputs, not direct copies of source material.
Who is it for?
- Jazz and blues musicians looking for fresh melodic ideas for practice
- Students exploring chord progressions and phrase structure
- Composers making quick sketches and variations
- Players who want to experiment with harmony, motifs, and rhythmic profiles
Getting started
Shape the phrase
Draw the blue (pitch) and orange (rhythm) contours in the piano roll, or tap Random contour / Random rhythm.
Generate and listen
Tap Randomize seed for a new variation, then tap Play to hear the result.
Fine-tune in Settings
Open Settings for tempo, key, length, probability controls, and Motif match.
Blue — Pitch contour
Guides the overall melodic direction and register.
Orange — Rhythm contour
Guides rhythmic density and note-duration choices.
Drawing on iPhone and iPad: draw in the rightmost 30% of the piano roll to edit the pitch contour; draw elsewhere in the piano roll to edit the rhythm contour.
Key features
- 73 ready-made jazz and blues chord chains
- Automatic melody and accompaniment generation
- Editable pitch and rhythm contours
- Piano-roll view with playback cursor
- Manual and randomly generated harmony
- Custom motifs and motif presets
- Adjustable key, length, tempo, swing, and reverb
- Controls for variation and melodic character
- SoundFont playback with saxophone, piano, and strings
- MIDI and MusicXML export
Quick reference
These controls appear on the main screen or in Settings. Most changes require a new generation to take effect; playback tempo, reverb, swing, and Play melody 8ve up affect playback immediately.
| Control | What it does |
|---|---|
| Randomize seed | Creates a new deterministic variation. Chords stay fixed when using a selected or manual chain. |
| Contour strength | How strongly the blue pitch contour pulls generated pitches. |
| Rhythm contour | How strongly the orange contour affects note durations and rhythmic density. |
| Use extremes | Random contours reach high and low areas with smooth curves instead of sharp spikes. |
| Harmony complexity | Richer harmonic color in both chords and melody. |
| Temperature | Randomness in probability choices: low = steady, high = surprising. |
| Motive max / gap | How often and how frequently custom motifs may appear in one piece. |
| Chord source | Manual chords uses your typed or preset chain; Random chords generates harmony from models. |
| Reharmonize melody | Rewrites generated harmony to better fit the finished melody when no fixed manual chain is used. |
| Motif match | Weimar phrase-similarity threshold for learned motif relations (default 0.40). |
Tip: If the melody feels too wild, lower Temperature, Chromaticism, and Leap amount. If it feels too cautious, raise those and Harmony complexity.
Frequently asked questions
How do I keep the same chords and generate a new melody?
Choose a Chord chain preset or use Manual chords, then tap Randomize seed. The selected or manually entered chord chain remains fixed while the melody and accompaniment are regenerated.
How do I edit the blue and orange curves?
On iPhone and iPad, draw in the rightmost 30% of the piano roll to edit the blue pitch contour. Draw elsewhere in the piano roll to edit the orange rhythm contour.
Why does a selected chord chain repeat?
A progression shorter than the selected piece length repeats automatically. A longer progression is clipped to the chosen number of bars.
How can I make the melody less unpredictable?
Lower Temperature, Chromaticism, and Leap amount. Increasing Tonal stability also favors notes that feel more settled in the selected key.
What should I do if there is no sound?
Check the device volume and make sure playback is running. Stop playback, return to the app, and tap Play again if the audio device needs to reopen.
Can I export the generated music?
Yes. Use Export MIDI or Export XML to save the current melody and harmony for other music software.
What do red notes in the piano roll mean?
Red notes belong to accepted custom motif groups. Motif groups are validated after generation so isolated red notes should not remain.
Support
Need further assistance?
Include your device model, iOS version, app version, and a short description of the issue when contacting support.
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