The JACK Audio Connection Kit

Using the JACK Audio Connection Kit (jack and qjackconnect), applications can exchange audio data with each other and with the sound card.This is only possible if the respective application has a JACK interface. JACK support has become a standard feature, so there are many applications that have the needed interface.

Figure 18.9. QJackConnect — a Patchbay for Jack

QJackConnect — a Patchbay for Jack

To use JACK, first start the engine with jackd -d alsa -d hw:0. JACK was designed to achieve a low latency. Therefore, the engine should run with real-time priority. For more information, read the file /usr/share/doc/packages/jack/README.SuSE.

The patchbay QJackConnect assists in tracking the JACK clients running in your system. Following the program launch with qjackconnect, the clients with readable ports are listed on the left side and the clients with writable ports are listed on the right side. If no JACK clients were started, the lists initially only display the inputs and outputs of the sound card. The lists are updated automatically as the port configuration changes.The ports are displayed in a tree view under the client. Connect individual ports by selecting them from the lists and clicking Connect. Connect multiple ports simultaneously by selecting clients.