MbiraGen is a semi-generative sequencer plugin that produces MIDI notes.

It is based on a sequence of up to 12 “melodies”. Each melody can have up to 4 variations which are selected round-robin. A Melody is a 5×4 grid where the vertical direction indicates note pitch and the horizontal direction indicates time.

Pitches are assigned based on a combination of settings: the tonic note, the scale, the mode, the interval assigned to the melody, and the individual scale degrees represented by the vertical positions in a melody.

In addition to the melody sequencer there is a velocity sequencer, controls for sync time, note length, velocity jitter, note length jitter, and 2 additional sequencers that can apply variations to the melodies as they are being played. These variations provide the drift and randomness that keeps the pattern from feeling too repetitive.