Jack OS X is a Mac OS X implementation of the Jack Audio Connection Kit (Jack). Jack is a low-latency audio server, written originally for the GNU/Linux operating system. It connects any number of different applications to a single hardware audio device; it also allows applications to send and receive audio to and from each other. Jack focuses on two key areas: synchronous execution of all clients, and low latency operation.

Jack OS X installs everything necessary to take full advantage of Jack on OS X. This includes:

• The Jack server
  The infrastructure you need in place to use Jack.
• The Jack Audio Server (JAS)
  JAS is a CoreAudio "user space" driver that allows any OS X CoreAudio application to become a Jack client.
• The Jack audio plugins
  Both AU and VST "Jack-aware" audio plugins are provided, which can further expand the limitless audio routing possibilities when using Jack. Both VST formats (Mach-O and CFM) are provided.
• The JackPilot application
  JackPilot offers an easy to use GUI interface that allows you to control the Jack server, and manage the audio connections between applications and/or plugins.