n0t0miz0r was created to provide a simple and fast solution for generating infinitely randomized output, regarding the pitch of a given note. This is quite handy if you do not have a faulty sequencer or an analog modular synthesizer with a sequencer option at hand. For 80’s-style electronic dance basslines for example, unpredictable randomness is mandatory.
MbiraGen is a free semi-generative sequencer vst plugin that produces MIDI notes 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.
Nova3 is a free VST Generative Sequencer plugin. The plugin is for Windows only, and includes an x32 and x64 version.
BlueARP is a free VST MIDI Arpeggiator with pattern sequencer style, designed for electronic music genres.
RPS-1 is a free pattern sequencing VSTi plugin designed primarily for the rapid creation of percussion sequences with random variations.