Seq66 is a loop based midi sequencer that provides the functionality needed for a live performance. It is a refactoring of the Qt version of Sequencer64 with modern C++ and with a lot of krufty buildup removed. Sequencer64 was based on the classic Seq24, styled after the Akai MPC line, the Kawai Q80 sequencer, or the popular Alesis MMT-8

Major changes:

Non Session Manager: Handles stopping and saving, display of details about the session.

User interface: Using Qt 5 for the user-interface (good cross-platform support) based on Kepler34. Removed the sequencer64 "grid of sets" in favor of unlimited external live grid windows. Added tabs for management of sets, mute-groups, song mode, pattern editing, event-editing, play-lists, and session management. Added a live frame using buttons to match Qt theming, a color for each sequence can be chosen to make them stand out. The Qt 5 GUI is the only official GUI of Seq66.

Configuration files:  Supported configuration files: ".rc", ".usr", ".ctrl", ".mutes", ".playlist", and ".drums" (note-mapping).

Internal: More consistent use of modern C++, including lambda functions. Additional performer callbacks to reduce the need for polling in the user-interface. Seq66 has builds for ALSA/JACK, PortMidi, Windows, and a command-line/daemon. MIDI devices are detected, inaccessible devices are ignored, and playback (e.g. to the Windows wavetable synthesizer) work. It is built easily via Qt Creator or qmake, using MingW.

Software type
Software language
Software features
JACK Transport
Piano roll
Step/grid sequencer
Chris Ahlstrom (ahlstromcj)

Recent releases Release Date
Seq66 0.99.7 19 Jul '23
Seq66 0.99.5 20 May '23
Seq66 0.99.4 30 Apr '23
Seq66 0.99.3 19 Apr '23
Seq66 0.99.2 4 Mar '23
Seq66 0.99.1 27 Nov '22
Seq66 9 18 Jul '22
Seq66 1 Jun '22
Seq66 0.98.9 29 May '22
Seq66 0.98.8 23 May '22