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RESONON

Send MIDI to a Synth or DAW

A MidiTrack plays its pattern out of a MIDI port on one channel, chosen with >>. Every method is in the MIDI reference; the port keys are in Preferences.

Declare an output port

Section titled “Declare an output port”

Ports belong to the machine, so they are declared in ~/.resonon/preferences.toml, not in the piece. The piece names a port by its alias:

[[midi.outputs]]
alias = "synth"
port  = "IAC Driver Bus 1"

resonon --list-ports prints a ready-to-paste entry for every attached device, and resonon setup writes the entries for you. The port name matches exactly, then as a substring, so "IAC" finds "IAC Driver Bus 1". Run reload_preferences() to put a change in force without restarting.

Play a pattern on a track

Section titled “Play a pattern on a track”

Create a track, route it to the port with >>, and send it a pattern with <<:

let lead = MidiTrack("lead");
lead >> MidiOutput("synth");
lead << [C4 E4 G4 E4];


PLAY;

The track plays on channel 1 at velocity 100. A new track has no output — Live’s “No Output” — so until the >> line runs it sends nothing. Send it another pattern at any time; the new one starts on the next cycle.

Use several channels

Section titled “Use several channels”

Give MidiOutput a channel as its second argument. A multi-timbral synth or a DAW plays each channel with its own sound:

let lead  = MidiTrack("lead");
let bass  = MidiTrack("bass").set_velocity(80);
let drums = MidiTrack("drums").set_velocity(110);


lead  >> MidiOutput("synth", 1);
bass  >> MidiOutput("synth", 2);
drums >> MidiOutput("synth", 10);


lead  << [E5 D5 C5 D5];
bass  << [C3 _ C3 G2];
drums << [C2 _ D2 _];


PLAY;

Channel 10 is General MIDI drums.

Send tracks to different ports

Section titled “Send tracks to different ports”

Declare a port per destination, each under its own alias:

[[midi.outputs]]
alias = "daw"
port  = "IAC Driver Bus 1"


[[midi.outputs]]
alias    = "synth"
port     = "Prophet Rev2"
optional = true

optional = true marks gear that is not always plugged in; its absence is expected instead of reported. Route each track to its alias, and move it with another >>:

let pad  = MidiTrack("pad");
let lead = MidiTrack("lead");


pad  >> MidiOutput("synth");
lead >> MidiOutput("daw", 2);     // to the DAW, channel 2
lead >> MidiOutput("synth", 5);   // to the synth, channel 5
lead >> nowhere;                  // no output: the track keeps its pattern and sends nothing

A track playing a pattern moves to the new port or channel on the next cycle, with its CC and input thru.

Set the velocity

Section titled “Set the velocity”

.set_velocity() sets the velocity for every note without a ^ velocity of its own. Give it a number, a pattern, or a signal:

use "std/signals" { Sine };


let melody = MidiTrack("melody");
melody >> MidiOutput("synth");
melody << [C4^100 D4 E4 F4^50];


melody.set_velocity(80);                          // fixed
melody.set_velocity([100 60 80 120]);             // one value per step
melody.set_velocity(Sine(0.5).range(60, 127));    // read as each note fires

The last call wins. The ^ velocities on C4 and F4 always stay.

Play a DAW instrument

Section titled “Play a DAW instrument”
  1. Enable a virtual port. On macOS, open Audio MIDI Setup, choose Window → Show MIDI Studio, double-click IAC Driver, and check Device is online.
  2. Declare it as an output, as above.
  3. In the DAW, enable the port as a MIDI input, create an instrument track, set its MIDI input to the port, and turn on input monitoring.
  4. Play a track from resonon. To record it as a MIDI clip, arm the DAW track and record.

For several instruments, create one DAW track per channel, all listening to the same port.

Check what is connected

Section titled “Check what is connected”
print(midi_ports());       // every output port on the system
print(midi_connected());   // {alias: port} for each connected port
midi_routing_report();            // ports, tracks and clock, in one summary
Section titled “Related”