The JACK Audio Connection Kit or JACK is a sound server daemon that provides low latency connections between so-called jackified applications, for both audio and MIDI data. It is created by Paul Davis and others. The server is licensed under the GNU GPL, while the library is licensed under the GNU LGPL.

JACK can use ALSA, PortAudio, CoreAudio, FreeBoB, FFADO and (still experimental) OSS as its back-end. As of 2008 it runs on Linux, FreeBSD and Mac OS X. There is also a version 2 in the works, JACKDMP, which supports Windows.

Applications

Some software that works with JACK:

• Aqualung – a GTK based music player
• Ardour – a free digital audio workstation program for Linux and OS X.
• Baudline – a signal analysis tool
• CheeseTracker – an Impulse Tracker clone
• ChucK – a real-time audio programming language
• Freqtweak – a digital EQ
• Hydrogen – an advanced drum machine
• LMMS – a free music sequencer and software synthesis program for Linux, OS X and Windows.
• MusE – a Qt-based MIDI/audio sequencer
• Music Player Daemon – what the name says. A daemon that runs in the background and plays music.
• Pure data – a graphical programming language for multimedia
• qjackctl – a Qt based tool to control JACK
• Rosegarden – a free digital audio workstation program for Linux
• SuperCollider – a real-time audio programming language
• XMMS – a free music player for X11
• XMMS2 – client/server based redesign of XMMS
• ZynAddSubFX – an opensource software synthesizer
• MOC – A ncurses based music player

As of 2007, there are many applications with JACK support; every well known video player supports JACK as audio output, and nearly every audio playing application for Linux supports JACK output.

Libraries

• Allegro - a game programming library
• bio2jack - a library that allows for simple porting of blocked I/O (bio) OSS/ALSA audio applications to JACK
• libjackasyn - a library that converts programs written for the OSS system into JACK-aware applications

See also

• LADSPA
• Free audio software
• PulseAudio
• aRts

External links

• Official Website
• JACK Design Documentation