Carla is a fully-featured audio plugin host, with support for many audio drivers and plugin formats. It's open source and licensed under the GNU General Public License, version 2 or later.
- LADSPA, DSSI, LV2 and VST2, VST3 and AU plugin formats
- SF2/3 and SFZ sound banks
- Internal audio and midi file player
- Automation of plugin parameters via MIDI CC
- Remote control over OSC
- Rack and Patchbay processing modes, plus Single and Multi-Client if using JACK
- Native audio drivers (ALSA, DirectSound, CoreAudio, etc) and JACK
In experimental phase / work in progress:
- Export any Carla loadable plugin or sound bank as an LV2 plugin
- Plugin bridge support (such as running 32bit plugins on a 64bit Carla, or Windows plugins on Linux)
- Run JACK applications as audio plugins
- Transport controls, sync with JACK Transport or Ableton Link
Carla is also available as an LV2 plugin and VST2 plugin.
Note: While the software is classified as free, it is actually donationware. Please consider making a donation to help support development.