Carla is a fully-featured modular audio plugin host, with support for many audio drivers and plugin formats.
It has some nice features like transport control, automation of parameters via MIDI CC and remote control over OSC.

Carla currently supports LADSPA (including LRDF), DSSI, LV2, VST2, VST3 and AU plugin formats, plus SF2 and SFZ file support.
It uses JACK as the default and preferred audio driver but also supports native drivers like ALSA, DirectSound or CoreAudio.

There are 4 types of engine processing:

• Single-client: (JACK driver only)
  Same as Multi-client, except that all JACK ports belong to a single master client.
  This is needed when a setup doesn’t support multi-client JACK apps, such as LADISH.
• Multi-client: (JACK driver only)
  Yese plugin imwe chete inoburitswa semutengi mutsva weJACK. Audio uye MIDI zviteshi zvakanyoreswa sezvinodiwa.
• Rack:
  Plugins inogadziriswa muhurongwa, kubva kumusoro kusvika pasi.
  Mapulagi ane asiri-stereo odhiyo chiteshi haatsigirwe, asi yekumanikidza-stereo sarudzo inowanikwa kune avo veMono.
• Patchbay:
  Modular patchbay modhi, senge muJACK Multi-client uye mamwe akawanda modular application.
  Yese plugin inowana yayo canvas boka uye zviteshi zvinokutendera kuti ubatanidze plugin odhiyo uye MIDI.