Qtractor

Qtractor is an audio/MIDI multi-track sequencer application written in C++ with the Qt framework. Target platform is Linux, where the Jack Audio Connection Kit (JACK) for audio and the Advanced Linux Sound Architecture (ALSA) for MIDI are the main infrastructures to evolve as a fairly-featured Linux desktop audio workstation GUI, specially dedicated to the personal home-studio.

Features:

- Multi-track audio and MIDI sequencing and recording.
- Developed on the Qt C++ application and UI framework [1].
- Uses JACK [2] for audio and ALSA [3] sequencer for MIDI
as multimedia infrastructures.
- Traditional multi-track tape recorder control paradigm.
- Audio file formats support: OGG (via libvorbis [6]),
MP3 (via libmad [7], playback only), WAV, FLAC, AIFF
and many, many more (via libsndfile [4]).
- Standard MIDI files support (format 0 and 1).
- Non-destructive, non-linear editing.
- Unlimited number of tracks per session/project.
- Unlimited number of overlapping clips per track.
- XML encoded session/project description files (SDI).
- Point-and-click, multi-select, drag-and-drop interaction
(drag, move, drop, cut, copy, paste, paste-repeat, delete, split, merge).
- Unlimited undo/redo.
- Built-in mixer and monitor controls.
- Built-in connection patchbay control and persistence
(a-la QjackCtl [16]).
- LADSPA [5], DSSI [11], native VST [12] and LV2 [13] plug-ins support.
- Unlimited number of plug-ins per track or bus.
- Plug-in presets, programs and chunk/configurations support, including
native VST FXB/FXP file support.
- Unlimited audio/MIDI effect send/return inserts per track or bus.
- Loop-recording/takes.
- Audio/MIDI clip fade-in/out, cross-fade (linear, quadratic, cubic).
- Audio/MIDI clip gain/volume, normalize, export.
- Audio/MIDI track and plugin parameter automation (dynamic curves,
sample&hold, linear and spline modes).
- Audio clip time-stretching (WSOLA-like or via librubberband [9]),
pitch-shifting (via librubberband [9]) and seamless sample-rate
conversion (via libsamplerate [8]).
- Audio/MIDI track export (mix-down, render, merge).
- Audio/MIDI metronome bar/beat clicks.
- Unlimited tempo/time-signature map.
- Unlimited location/bar markers.
- MIDI clip editor (matrix/piano roll).
- MIDI instrument definitions (a-la Cakewalk(tm) (*.ins) [18]);
SoundFont (*.sf2) and MIDI Names XML (*.midnam) files also supported.
- MIDI controller mapping/learn/assignment (mixer and plug-in parameters).
- MIDI system exclusive (SysEx) setups.
- JACK transport sync master/slave.
- JACK session support.
- NSM (Non Session Management) support [15].
- MMC control surface enabled.
- MIDI Clock, Song Position cueing support.
- Configurable keyboard and MIDI controller shortcuts.

0.7.8 2016-06-22 The Snobby Graviton Beta

- MIDI file track names (and any other SMF META events) are now converted to and from the base ASCII/Latin-1 encoding, as much to prevent invalid SMF whenever non-Latin-1 UTF-8 encoded MIDI track names are given.
- MIDI file tempo-map and location markers import/export is now hopefully corrected, after almost a decade in mistake, regarding MIDI resolution conversion, when different than current session's setting (TPQN, ticks-per-quarter-note aka. ticks-per-beat, etc.)
- Introducing LV2 UI Show interface support for other types than Qt, Gtk, X11 and lv2_external_ui.
- Prevent any visual updates while exporting (freewheeling) audio tracks that have at least one plugin activate state automation enabled for playback (as much for not showing messages like "QObject::connect: Cannot queue arguments of type 'QVector'"... anymore).
- The common buses management dialog (View/Buses...) sees the superfluous Refresh button finally removed, while two new button commands take its place: (move) Up and Down.
- LV2 plug-in Patch support has been added and LV2 plug-ins parameter properties manipulation is now accessible on the generic plug-in properties dialog.
- Fixed a recently introduced bug, that rendered all but one plug-in instance to silence, affecting only DSSI plug-ins which implement DSSI_Descriptor::run_multiple_synths() eg. fluidsynth-dssi, hexter, etc.


0.7.7 2016-04-27 The Haziest Photon Beta

- LV2 UI Touch feature/interface support added.
- MIDI aware plug-ins are now void from multiple or parallel instantiation.
- MIDI tracks and buses plug-in chains now honor the number of effective audio channels from the assigned audio output bus; dedicated audio output ports will keep default to the stereo two channels.
- Plug-in rescan option has been added to plug-ins selection dialog (yet another suggestion by Frank Neumann, thanks).
- Dropped the --enable-qt5 from configure as found redundant given that's the build default anyway (suggestion by Guido Scholz, thanks).
- Immediate visual sync has been added to main and MIDI clip editor thumb-views (a request by Frank Neumann, thanks).
- Fixed an old MIDI clip editor contents disappearing bug, which manifested when drawing free-hand (ie. Edit/Select Mode/Edit Draw is on) over and behind its start/beginning position (while in the lower view pane).


0.7.6 2016-04-05 A Hazier Photon Beta
0.7.5 2016-03-21 Hazy Photon Beta.
0.7.4 2016-01-28 The Tackiest Gluon
0.7.3 2015-12-29 A Tackier Gluon
0.7.2 2015-12-10 Tacky Gluon Beta
0.7.1 2015-10-09 Meson Dope Beta
0.7.0 2015-07-24 Muon Base Beta