miniOMsynth is a user-friendly synthesizer app made in MaxMSP, to facilitate OSC playback from OpenMusic in macOS.

Given that some of the existing external applications for OM playback may present compatibility issues — e.g. outdated dependencies — this is meant to be an easy-to-use alternative for OM users.

miniOMsynth has microtonal playback support for up to 16 MIDI channels, via OSC or MIDI. When the application is launched, each channel is assigned a randomly generated waveform and envelope to provide instant timbral contrast between channels. The generated waveforms and envelopes can also be edited, saved, and loaded, via the synth editor, as a way to provide timbral consistency from session to session. The saved files will consist of 16 sound files in .aiff format and a .JSON file. To load a saved synth palette, simply select the corresponding .JSON file and miniOMsynth will take care of the rest.

miniOMsynth also contains a mixer window to individually control panning and volume for each channel.

• In OpenMusic Preferences/MIDI, enable OSC communication between OM and miniOMsynth, by setting the default score player to osc-scoreplayer. Check the Force Score Player box.

• If OSC playback does not work, miniOMsynth also has MIDI playback support. In OpenMusic Preferences/MIDI, set the default score player to midi-player. Then, in Ports setup, include to miniOMsynth 1 as an input device. Do the same in miniOMsynth/input settings/MIDI input/.