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Address: User:Crantila/FSC/Sequencers/Qtractor

Features and Strengths

This is what Qtractor is good for. It seems to me that Qtractor wants to meld Ardour and Rosegarden.

When to Use Qtractor


When to Avoid Qtractor


Requirements and Installation

Is this available from RPM Fusion and Planet CCRMA? Hmm... I wonder which to use

Software Requirements

  • libvorbis
  • libmad
  • jack-audio-connection-kit
  • slv2
  • rubberband
  • libogg
  • liblo
  • libsndfile
  • libsamplerate

There are no large dependencies. If you have not yet installed QjackCtl for JACK (jack-audio-connection-kit), then it is recommended that you do so at this time. See the JACK portion of this guide for more information.


  • In PackageKit or KPackage kit, install qtractor, or run su -c 'yum install qtractor'


This probably isn't necessary, but it's nice to know.

Go to 'View > Options' to see the configuration window.

"Audio" Tab:

  • Capture/Export:
    • You can choose the file type, and sample format or quality, for exportation of audio.
    • The default choice is OGG Vorbis at "4" quality.
    • Standard ".wav" format is called "WAV Microsoft"
    • Standard ".aiff" format is called "AIFF Apple-SGI"
    • Many options are available, but I recommend FLAC, which is FLOSS, lossless, and compressed.
    • A higher number for sample format will yield greater quality:
      • CD Audio has 16-bit samples,
      • Most audio is recorded, and hardware supports, 24-bit samples,
      • Sample sizes larger than "Signed 24-Bit" are only practically useful if your hardware supports those sample sizes.
  • Playback:
    • Sample-rate converter type:
      • Sinc (Best Quality)
      • Sinc (Medium Quality)
      • Sinc (Fastest)
      • Zero Order Hold
      • Linear
    • Transport mode:
      • Full
      • Master
      • Slave
      • None
    • Automatic time-stretching
    • WSOLA time-stretching
    • WSOLA quick seek
    • Dedicated audition/pre-listening player outputs (provided in JACK; Ardour does this by default; it's useful for this)
  • Metronome
    • Enable audio metronome
      • File (bar)
      • File (beat)
    • Dedicated audio metronome outputs (also like Ardour... right?)

"MIDI" Tab:

  • Capture/Export
    • File format:
      • SMF Format 1
      • SMF Format 0
    • Quantize: aligns events to beats as closely as specified.
      • None
      • Beat
      • Beat/2
      • Beat/etc.
  • Playback
    • Queue timer (resolution):
      • (default)
      • system timer (1000Hz)
      • PCM playback-0-0-0 (slave), etc. ???
  • Control
    • MMC:
      • None
      • Input
      • Output
      • Duplex
    • Device: "(Any)" or 0-127
    • SPP: None, Input, Output, Duplex
    • Dedicated MIDI control input/output (like Rosegarden)
  • Metronome
    • Enable MIDI metronome
    • Channel: (default 10)
    • Note (bar): choose percussion instrument, velocity, duration
    • Note (beat): choose percussion instrument, velocity, duration
    • Dedicated MIDI metronome output

"Display" Tab: Pretty much self-explanatory

"Plugins" Tab: Allows you to choose directories for LADSPA, LV2, and DSSI plugins, adding multiple directories of each kind. Also,

  • Instruments
    • Dedicated audio outputs (check-box): ????

Session Set-up

Qtractor includes the important part of QjackCtl's interface, so it is not necessary to run both programs together. However, you may wish to use other features of QjackCtl, like its ability to save a "patch bay."

To get Qtractor's implementation of QjackCtl's "Connections" window, you'll have to click on the "Connections" button on the toolbar, or 'View > Connections' or F8. Qtractor's "MIDI" tab is equivalent to QjackCtl's "ALSA" tab.

  1. Start Qtractor.
    • If JACK isn't already running, then Qtractor will start it automatically. If you were using PulseAudio, but do not use the PulseAudio->JACK thing, then PA won't work while JACK is running.

!! When creating a MIDI track, the "omni" check-box determines whether that track will accept input from any MIDI channel, or just the one to which it's assigned !!

!! To move the transport to a particular point, shift-click in the measure number !!

!! You can change whether you want to follow the transport by auto-scrolling, with the button on the toolbar !!

!! In the matrix editor and the main screen, when you want to scroll left-right, hold control and use the mouse's scroll wheel !!

!! In matrix editor, "Tools" to adjust velocity is "Resize" and you can set it absolutely !!

!! So that Qtractor knows your "instruments" and patch names and stuff, you'll need to import your SoundFont (if you're using Qsynth) !!

  1. Go to 'View > Instruments'
  2. Click "Import"
  3. Navigate to /usr/share/soundfonts
  4. Import whichever SoundFonts you would like to use (like the default FluidR3 GM).
  5. This is all tha Qtractor needs for general configuration.
  6. For each MIDI track that you have, either at creation or later by accessing the "Track Properties" window (for example, by right-clicking on the track's info-box in the left column and then "Track Properties")
    1. If it says "(No instrument)" then choose a SoundFont and change to that.
    2. The "Bank Select Method" can normally be left alone.
    3. Choose a bank (they all have different programs/sounds).
    4. Choose a program (this is the actual sound).
    5. Click "OK" to accept the new settings.

!! to export MIDI tracks with audio in Qtractor !! (still needs to be tested) Play through the file in Qtractor, while routing the MIDI output into a track that's being recorded in Qtractor... effectively converting the MIDI to audio so that when you export the audio, it will all be done together. Also explain why you have to do this. Also, it's probably better to re-record the audio AND the MIDI, because then you will have the proper balance applied in a single audio track.

  1. Create a new, empty audio track in Qtractor.
  2. Check the the following is connected to Qtractor's master bus:
    • All of Qtractor's audio output that you want in the final recording.
    • All of your MIDI synthesizer's output ("all of Qsynth's output") that you want in the final recording.
    • Nothing else.
  3. Move Qtractor's transport to the start of the session.
  4. Arm the new track onto which you intend to record.
  5. Un-arm all other tracks.
  6. Arm Qtractor's transport.
  7. Press "Play" on the transport, and wait as the session plays through.
  8. Unfortunately, for this part, there is no way to go faster than real-time.
  9. Qtractor will not automatically stop the transport upon reaching the end of the previously-recorded material.
  10. When Qtractor reaches the end of the previously-recorded material, stop the transport, un-arm the new track, and create a saved copy of the Qtractor file... or export it immediately, I'm not sure...