Fishtail

Fishtail is a generative MIDI instrument and composition system for Mac. It creates complete, repeatable musical takes from a compact arrangement, then performs them through software instruments in Logic Pro, other compatible AUv3 MIDI hosts, or eight named standalone CoreMIDI sources.

COMPOSE WITH FORM

Build sections with key, mode, meter, cadence, musical role, treatment, expression and Bloom controls. Shape the whole piece with gentle D4 or wide D20 generation. Keep generated takes, return to an earlier take and choose the play order.

TUNE FROM AN EXACT REFERENCE

Set an exact pitch reference—including C4 = 256 Hz—and choose Equal Temperament, Just Major, Just Minor, Pythagorean, Werckmeister III or Fishtail's experimental intonation models.

PLAY POLYPHONIC ALTERNATIVE INTONATION

Choose normal 12-ET MIDI, global pitch bend, per-part pitch bend or MPE pitch bend. In Logic Pro, Fishtail can send seven fixed voices on MIDI channels 1–7, so Bass, Tenor, Alto, Soprano, Bloom Bass, Bloom Octave and Shimmer can each have their own instrument, effects, pan and fader.

SWIM BETWEEN MAC APPS

The standalone app publishes eight clearly named CoreMIDI sources: one combined source plus seven separate parts. It can publish 24 PPQN MIDI Clock and Start/Stop on the combined source, with timestamped scheduling tied to the audio render timeline. CoreMIDI publishing is on by default and can be turned off in Standalone Settings.

WORK WITH YOUR HOST

Join an Ableton Link session for shared tempo, beat, phase and optional start/stop. Save and reopen Fishtail project documents or host projects with Fishtail's applied tuning, MIDI output mode, Live MIDI Route and playback Rate restored. Export MIDI plus supported tuning and analogue-CV materials.

Fishtail is a composition instrument, not a sound source. Load Fishtail in the Instrument slot of a software-instrument track and route its MIDI output to one or more receiving instruments, or route the standalone CoreMIDI sources into another Mac instrument.

Requirements: macOS 14 or later. Universal support for Apple silicon and Intel Macs.

Artwork by Ocular Debris.