Registered 2010-08-30 by Rafał Cieślak

A MIDI sequencing application helpful for music composers and live artists.

More details and demonstrations can be found at

harmonySEQ is a fully configurable and intuitive MIDI sequencing studio, allowing user to set up many separate (but synchronized) sequencers and bind some polyphonic melodies or patterns to them. It reacts on user-defined events, making it easy to trigger any action using keyboard or an external MIDI controller. It may be useful for live artists or music composers. Is is not a synthesizer, it does not produce any sound, it sends MIDI notes to other applications in some pattern, mainly repeating same or similar sequences.
harmonySEQ is still under heavy developement. However, at this point of development it is already a useful and widely adaptive sequencer studio. I do not guarantee it's stable, but there is no risk from using it. Try connecting it with any synthesizer you like, and have fun. If you want to share your opinion or ask any question, feel free to contact.

    - Any number of synchronized sequencers
    - Each can play different pattern of notes to different MIDI channels on different velocities
    - Melodies/patterns may have unequal lengths and resolutions, but they will still be synchronized
    - Sequencers use only notes from the chord that is bound to them, which makes it easy to keep them in tune
    - Transposing, muting, changing chords and changing melodies can be done on the go, during the performance.
    - Heavily customizable events-actions system, which one may use to make harmonySEQ react on events like keypress, noteon, etc.
    - Saving and loading sequencer sets to files
    - Multilingual GUI, (currently English, Polish and partially Turkish, please contribute and help translating harmonySEQ)

As for now harmonySEQ works on Linux only, versions for other operating systems are not considered. The application uses ALSA (asound) library, and GTKmm for graphical interface.

A PPA for harmonySEQ can be found at

Project information

Rafał Cieślak
Rafał Cieślak

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trunk series is the current focus of development.

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Latest version is 0.16
released on 2012-02-04

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