PhraseLab

Compose with PhraseLab, a MIDI composition tool that writes four-part arrangements grounded in music theory: not machine learning.

Pick a key, choose a genre, and hit Generate. PhraseLab gives you chords, melody, bass, and arpeggios, all harmonically coherent and ready to drag into your DAW.

The real workflow starts after that first click: lock the parts you like, regenerate the rest. Keep the chords but want a new melody? Lock the chords, hit regenerate. Happy with the melody too? Lock it and keep iterating on the bass and arps until everything clicks.

Key Features

• Four Harmonically-Locked Lanes: Chords, Melody, Bass, and Arpeggios, all musically aware of each other.
• Lock & Regenerate Workflow: protect what you like, regenerate the rest. Iterate until it clicks.
• 14 Genre Profiles: Ambient, Cinematic, Lo-Fi, Electronic, Pop, Neo-Classical, Dark/Horror, Experimental, R&B, Synthwave, Jazz, Trap, Meditation, and World.
• 31 Scales: from Major and Minor through Dorian, Lydian, and Phrygian to Hirajoshi, Double Harmonic, and Enigmatic.
• Chord Editor: manually tweak, swap, or lock individual chords in the progression.
• Import Your Own Chords: bring in a MIDI file, PhraseLab detects the chords and builds melody, bass, and arps around them.
• Deep Parameter Control: Complexity, Tension, Contour, Density, Swing, Gate, and more per lane.
• Drag & Drop MIDI Export: drag any lane (or all four) straight into your DAW.
• Built-in Plugin Hosting: load your favourite synths directly inside PhraseLab.
• Standalone & Plugin: run it on its own or inside your DAW as VST3 / AU.
• Music Theory, Not AI: powered by Markov chains and probability matrices, giving you musically coherent results every time.
• Cross-Platform: macOS (Intel & Apple Silicon) and Windows.

{See video at top of page}