What's 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.
Qtractor is free, open-source software, distributed under the terms of the
GNU General Public License (GPL)
version 2 or later.
Project page: http://sourceforge.net/projects/qtractor
Click on image to see more screenshots...
- Multi-track audio and MIDI sequencing and recording.
- Developed on the Qt C++ application an UI framework.
- Uses JACK for audio
and ALSA sequencer for MIDI
as multimedia infrastructures.
- Traditional multi-track tape recorder control paradigm.
- Audio file formats support: OGG (via libvorbis),
MP3 (via libmad, playback only),
WAV, FLAC, AIFF and many, many more (via libsndfile).
- 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, freeze)
- Unlimited undo/redo.
- Built-in mixer and monitor controls.
- Built-in connection patchbay control and persistence (a-la QjackCtl).
- LADSPA, DSSI, native VSTi and LV2 plug-in 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.
- 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), pitch-shifting (via librubberband) and seamless sample-rate conversion (via libsamplerate).
- 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));
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.
- MMC control surface enabled.
- MIDI Clock, Song Position Pointer (SPP) support.
- Configurable PC-keyboard and MIDI controller shortcuts.
The software requirements for build and runtime are listed as follows:
Optional (opted-in at build time):
- libvorbis (enc, file), Ogg Vorbis audio compression
- libmad, High-quality MPEG audio decoder
- libsamplerate, The secret rabbit code, C library
for audio sample rate conversion
- librubberband, Rubber Band Audio Time Stretcher,
an audio time-stretching and pitch-shifting library
- liblo, Lightweight OSC implementation
(needed for DSSI GUI and/or NSM support)
- DSSI, An API for soft synth plugins with custom user interfaces
- VST SDK, Steinberg's Virtual Studio Technology
- LV2, Audio Plugin Standard, the extensible successor of LADSPA
- liblilv, Lightweight LV2 implementation stack
- libsuil, Lightweight C library for loading and wrapping LV2 plugin UIs
- NSM, Non Session Management
Qtractor's already in some kind of beta stage of development and hence fully functional.
Though, the bleeding-edge development source tree is readily available from the sourceforge's public
2018-03-22 - Early Spring'18 Beta
- New View/Options.../Plugins/Experimental/Show plugins on
track list/left pane option is in effect on tracks that
are tall enough in height for their plugins list to fit
on the Bus column.
- Fixed a day-zero bug over the MIDI Insert (Send/Return)
pseudo-plugin, which was duplicating MIDI events onto
the next LV2 plugin in chain, causing strange hanging
notes, mutes, retriggerings and what not.
- MIDI track and clip note min/max range display now fixed.
- MIDI Program Change events (PC) now have their proper
program number as parameter, instead of value, on the
internal MIDI event representation.
- Merging MIDI clips while on SMF Format 0 has been fixed:
was merging always onto the same MIDI channel (2), most
often the wrong one, resulting in an empty or blank clip.
- When importing from standard MIDI files (SMF), set track
names from Mtrk TRACKNAME meta-events instead of filename.
- Avoid asking to save as to existing or just newly created
clip file-names, whenever possible.
- Disable singleton/unique application instance setup logic
when the display server platform is not X11.
- Whether to use native file browser/requester dialogs is
now an effective option when launching under NSM session
management (was once disabled initially).
- Content files are now saved as symlinks when saving to
JACK and/or NSM session directories/folders.
- Trying to get CC14 MSB+LSB (course+fine) running status
on, no matter whether each pairing event are under 200ms
- Possible VST plug-in GUI reparenting hack/fix on Qt5/Xcb.
Previous and older pre-releases, including the change log,
are also available here.
You can browse all files available for download, including binary packages, at
Qtractor Files on SourceForge.net.
The installation procedure follows the standard for source distributions.
Once under the extracted source directory:
and optionally as root:
This procedure will end installing the following files:
Just launch prefix
/bin/qtractor and you're off (hopefully).
Note that the default installation path prefix is
Qtractor holds its settings and configuration state per user,
in a file located as
Normally, there's no need to edit this file, as it is recreated and
rewritten everytime qtractor is run.
Probably plenty still, Qtractor maybe considered on beta stage already.
Qtractor is open source free software. For bug reports, feature
requests, discussion forums, mailling lists, or any other matter related
to the development of this piece of software, please use the
Sourceforge project page.
You can also find timely and closer contact information on my
personal web site.
The dated Qtractor quick start guide and user manual
for version 0.5.x has been authored by Seth Kenlon & Klaatu.
The older user manual for version 0.3.0 and before,
have been co-authored by James Laco Hines and Stephen Doonan.
Qtractor logo/icon is an original work of Andy Fitzsimon, borrowed from
the public domain openclipart.org gallery.
A special mention should also go to the translators of Qtractor, of course:
- Pavel Fric (cs)
- Guido Scholz (de)
- David Reyes Pucheta (es)
- Yann Colette (fr)
- Olivier Humbert (fr)
- Massimo Callegari (it)
- Takashi Sakamoto (ja)
- Esteban Viveros (pt)
- Alexandre Prokoudine (ru)
And, of course, last but not least, to all the past, present and future
contributors of the Qtractor Wiki.
Thank you all.