Ardour 5.5 released

Ardour 5.5 is now available, with a variety of new features and many notable and not-so-notable fixes. Among the notable new features are support for VST 2.4 plugins on OS X, the ability to have MIDI input follow MIDI track selection, support for Steinberg CC121, Avid Artist & Artist Mix Control surfaces, "fanning out" of instrument outputs to new tracks/busses and the often requested ability to do horizontal zoom via vertical dragging on the rulers. There are also the usual always-ongoing improvements to scripting and OSC support.

As in the past, some features including OSX VST support, Instrument Fanout, and Avid Artist support were made possible by sponsorship from Harrison Consoles.

If you're looking for information about Ardour 5.0, you'll want to read the release notes. Release notes for other older versions are linked in the list below.



  • Work around MIDI devices sending invalid timestamps on OSX.
  • Open Sessions with files referenced from removable drives on Windows.
  • Various fixes for NetBSD and FreeBSD.
  • Add MIDI Control Change at correct location when importing.
  • Update Region colors on theme change.
  • Fix/Support note name translations (e.g "Ré ♯").
  • Allow loading sessions with missing external files. [#7067, #7114]
  • Use distinct color identifier for meter clip indicator. [#7010]
  • Prevent panners being reset when switching to Aux sends and back. [#6893]
  • Use correct BBT offset when using Insert Time. [#7072]
  • Fix restoration of key bindings assigned to Windows+key. [#7037]
  • Prevent duplicate moves when selecting regions on shared playlists.
  • Fix crash when instrument instantiation fails on track creation.
  • Prevent infinite loop when calculating tick marks on low zoom levels.
  • Fix LTC-generator 24h wraparound
  • Correctly handle failed activation of Control Surface Modules
  • Fix Master Track moving down one position in Editor after Session reload. [#7080]
  • Mark Session state as changed when tracks are reordered. [#7093]
  • Improved fix for playback of linked MIDI Regions [#6541]
  • Fix to keep Meterbridge Window on top.
  • Fix for non-working buttons in Monitor Section after second Session load [#7098]
  • Fix LV2 state versioning with Session templates.
  • Include Aux Busses in default strip types in OSC Surface [#7090]
  • Fixes to Insert/Remove time dialog [#7072]
  • Fix intermittent hang when stopping PortaudioBackend [#7095]
  • Fix playlist XML nodes changing order on Session save [#7053]
  • Fix crash loading u-he Diva VST plugin on Windows
  • Fix Duplicating Tracks with Sidechains [#7117]
  • Fix incorrect Midi Region length when splitting
  • Fix for widget visibility with detached preferences window [#7002]
  • Fixes when creating MIDI notes in Sustained note mode [#7126]
  • Fixes when creating MIDI notes in Percussive note mode [#7130]
  • Fixes to Cut Mode to make the cut line visible and respect snap modifier
  • Fix inaudible Percussive notes being displayed at the end of the Region
  • Fix crash when editing pitch of notes to outside visible area [#7135]
  • Fix crash when deleting a MIDI Region while mouse over CC event
  • Fix concurrency/locking issue with Event Loop request invalidation [#7049]
  • Fix creation of playlists with duplicate names [#6523, #5681, #6497]
  • Fix output display for non-plugin processors in the Processor Box
  • Fix forwarding of output buffers by using correct channel count
  • Fix loading, recording & saving MIDI with PolyKeyPressure events [#6948]
  • Fixes to Duplicate Track [#7141, #7146]
  • Fixes to OSC Control Surface
  • Fix handling of pitch bend events by a-fluidsynth [#7140]
  • Fix for reading CAF audio files over a certain size

General Improvements

  • Many MIDI and Tempo related refactorings, fixes and improvements to performance, source code documentation and tests. (Thanks Nick)
  • Include Session utilities in the application installers/bundles.
  • Allow feedback loops from internal Sends to enable custom "Echo" chains.
  • Improved performance when reading and writing XML files.
  • Improved performance of Region export.
  • Snap to Track Strip boundaries when scrolling with arrow keys in the Editor.
  • Clicking on a Strip in the Mixer Strip List will move the Strip into view.
  • Snap to Mixer Strip boundaries when scrolling with arrow keys in the Mixer
  • Minor updates to Cubasish Theme.
  • Compensate for latency/correct alignment when exporting the Master Bus.
  • Improve automatic Track naming [#7092]
  • Add option to zoom in the time rulers using button press and dragging vertically. [#6768]
  • Speed up changes to AFL/PFL on large Sessions
  • Large improvements in time to process Solo changes [#7119]
  • Speed up Track/Bus creation time
  • Restrict ALSA input/output device selection to valid combinations
  • Speed up Track deletion when Editor Mixer Strip is visible


  • Many minor fixes and improvements
  • Support MIDI input follows Track selection. [#6744]
  • New MIDI -> Ports page in Preferences for managing MIDI port functionality and enabling MIDI input follows Track Selection.
  • Added support for Type 0 MIDI files and add option to split channels into tracks on import.
  • Added MIDI mapping for AKAI Midimix.
  • New MIDI Note selection XML format, existing note selections will be lost.
  • Improved editing in Percussive note mode


  • VST 2.4 plugin support on OSX
  • Add functionality to Fan out an Instruments outputs to new Tracks/Busses (video demo explanation at
  • Allow LV2 plugins to provide Midnam XML.
  • Increase maximum release time in a-comp.
  • Sort Instrument list alphabetically.
  • Updated internal versions of qm-dsp library and qm-vamp plugins.
  • Allow LV2 Plugins to signal state changes and mark Session state as changed.
  • Support LV2 PortGroup extension
  • Add support for output-channel/bus grouping in AU plugins


  • Mouse drags on plugin GUIs (editors) are now handled correctly when they end outside the window.
  • Video monitor "full screen" mode no long spans all screens


  • Added or improved Lua bindings for VAMP plugins, TempoMap, Basic MIDI model editing, Inter-Processor communication, Source, AudioSource, Route, Panner, Instrument
  • Add example script for Audio to Midi Transcription.
  • "Sound Smasher" example script added.
  • Add prototype script for converting polyphonic audio region to a MIDI region.
  • Add example script for instrument fan-out
  • Add example script to modulate parameters globally
  • Add support for calling ARDOUR.DSP Lua functions from UI scripts
  • Add example script to process Regions selected in the Editor
  • Add MIDI LFO example script

Control Surfaces

  • Added Support for Steinbergs CC121 Control Surface
  • Activate/Deactivate plugins via OSC
  • Added configuration files for the Avid Artist Control and Artist Mix Control surfaces.
  • Allow Aux Buses visibility to be controlled separately via OSC
  • Add OSC support to query strips internal sends [#7136]
  • Add OSC support to query plugins and their parameters [#7137]


  • Updated German translation (Edgar Aichinger)
  • Updated French translation (Olivier Humbert)


Ben Loftis, cooltehno, David Robillard, eighthkeepa, John Emmas, Kamil Rytarowski, Len Ovens, Michael Beer, Michiel de Roo, Nathan Stewart, Nick Mainsbridge, Nil Geisweiller, Nils Philippsen, Olivier Humbert, Paul Davis, Robert Scott, Robin Gareus, Tim Mayberry, W.P. van Paassen