A chord composing tool. dust doesn't output any audio itself but instead drives a DAW via MIDI.

Setup

Chord patterns

By default dust looks for a yaml file with chord patterns at ~/.config/dust/patterns.yaml.

See below for more on chord progression patterns.

Bitwig Studio MIDI

MIDI has only been tested with Bitwig, but should work with any DAW.

1. Setup virtual MIDI ports with sudo modprobe snd_virmidi
   • To have this automatically load on boot, edit /etc/modules and add snd-virmidi
2. Launch bitwig-studio
3. Setup Dust -> Bitwig (for sending chords/playing instruments)
   1. In Settings > Controllers, add a generic controller. In the MIDI input dropdown you should see several "Virtual Raw MIDI" devices.
   2. Select "Virtual Raw MIDI/1"
4. Setup Bitwig -> Dust (for synchronizing the clock)
   1. In Settings > Synchronization, find "Virtual Raw MIDI/1" and make sure both Clock and Start/Stop are active.

For me Virtual Raw MIDI/1 corresponded to the ports called Virtual Raw MIDI 0-0:VirMIDI 0-0 16:0.

By default, dust chooses the 2nd port (i.e. port 1, when 0-indexed) for both MIDI Input and Output, which should correspond to the "Virtual Raw MIDI/1". You can change this by using the --midi-in-port and --midi-out-port arguments; just pass in the index of the port to use instead.

See also: https://github.com/anton-k/linux-audio-howto/blob/master/doc/os-setup/virtual-midi.md

Usage

dust has two modes: "Performance" mode (default) and "Sequencer" mode. You can use M to switch between them.

Performance Mode

In this mode you can bind chords to the number keys 1-9. Use e.g. Alt-1 to select a chord to bind to the 1 key.

Alternatively, you can enter in a space-delimited progression by pressing p.

Sequencer Mode

In this mode you layout chords in a sequencer format, which will run when you hit play in your DAW.

Tips:

• Use hjkl to move across the sequencer grid.
• Use A and B to mark sections to loop.
• Use R to generate a new chord progression, or S to generate one from a starting chord.
• With a chord selected in the grid, use U and D to browse chords.

General tips

• Use v to apply a voice-leading algorithm to the chord progression. This looks for inversions that minimize finger movement across the progression.
• Use E to export to a MIDI file.

Defining chord progression patterns

See pattern.yaml.

The chord naming system here is a little different than the conventional roman numeral system, and designed to be less ambiguous and easier to represent with ASCII text. It consists of the following parts:

1. Optional: # or b symbols to flatten/sharpen the degree (e.g. if in CMaj, then bIII will give EbMaj).
2. The scale degree and mode of the chord is defined by a roman numeral. Uppercase is major, lowercase is minor.
3. Optional: The triad quality:
   • + for augmented (M3+a5)
   • - for diminished (m3+d5)
   • ^ for sustained 4 (P4+P5)
   • _ for sustained 2 (M2+P5)
   • 5 for power chord (+P5)
   • If absent, is either major (M3+P5) or minor (m3+P5) depending on the roman numeral
4. Optional: After :, additional intervals/extensions are expressed by scale degree (relative to the mode of the chord), and comma separated (optional).
   • Degrees can be prefixed with # or b to move them up or down a step
   • These do not stack; i.e. if you want to have a dominant 9th it needs to be written as V:b7,9 and not V:9
   • Note that this is different than conventional notation, which isn't really systematic! For example, the dominant 7th is conventionally notated as V7; a more straightforward notation would have this mean the major 7th. Here the dominant 7th is notated as V:b7 and the major 7th is notated as V:7.
   • This lets you create e.g. cluster chords, for example I:2
5. Optional: Specify an inversion by either:
   • Specifying the bass scale degree after /
     • E.g. III/3 sets the major 3rd to be the bass note
     • Thus e.g. I/3 is the first inversion and I/5 is the second inversion.
   • Specifying the inversion number after %
     • E.g. III%1 is the first inversion, III%2 is the second inversion, etc
     • Thus I/3 == I%1, I/5 == I%2, etc.
6. Optional: Shift the chord up an octave with >1 or down an octave <1.
   • E.g. I>1
7. Optional: After ~, specify a different relative key (you can think of this as the chord being "drawn from" that relative key)
   • E.g. V:b7~V is a secondary dominant (this would normally be notated V7/V)
   • This lets you modulate relatively easily too, e.g.: I vi IV VI:b7 ii VI~ii iv~ii