| The purpose of this pageIn order to ensure the correct sound card or audio interface is used some user and or system wide configuration may need
to be done but it only needs to be done once. It is likely that if the system just has onboard audio things will already work
just fine but there is probably some scope for performance tuning. Configuring your system for JACK Audio Connection KitAssuming IDJC is using a dedicated JACK sound server (not direct to Pipewire)
it is worthwhile making a simple JACK configuration file. The configuration file will determine the operating parameters of an automatically started JACK sound server. $ echo "/usr/bin/jackd -d alsa -r 44100 -p 256 -n 2" > ~/.jackdrc In this example a sample rate of 44100 was selected matching the vast majority of digital music out there.
Additionally a lowish latency of 256 samples was chosen. Too low a number will result in audio problems.
Too large and audio will be noticably delayed. The same is true for the number of buffers. Three buffers is
suggested for USB audio interfaces. Making JACK use a particular sound cardIt's a two step process of finding the names of all the sound cards and specifying
which one to use. $ cat /proc/asound/cards
 0 [Revolution71   ]: ICE1724 - M Audio Revolution-7.1
                      M Audio Revolution-7.1 at 0xd000, irq 19
 1 [nanoKONTROL    ]: USB-Audio - nanoKONTROL
                      KORG INC. nanoKONTROL at usb-0000:00:1d.0-2, full speed
$ jackd -d alsa -d hw:Revolution71 -r 44100 -p 256If specifying the card name failed try using the number to the left prefaced by 'hw:' without the quotes. 
$ jackd -d alsa -d hw:0 -r 44100 -p 256 Normally you would not need to specify hw:0 since it is the first sound device however you may have onboard
audio disabled in the BIOS, at the driver level, or in ALSA itself resulting in card 0 not appearing in
/proc/asound/cards. Enabling MIDI events$ jackd -d alsa -r 44100 --midi raw Only use the --midi option if you intend to use a MIDI device to control IDJC. For systems that run PipewireSome systems that are configured for Pipewire still use a real JACK server as a feed. To use Pipewire directly
start IDJC as follows. $ pw-jack idjc With IDJC using Pipewire directly, the JACK Ports menu can be used to select or
check the correct audio device(s) are in use. One of Pipewire's main advantages is an ability to connect audio applications together and share audio regardless
of whether they were created to use Pulseaudio or JACK. To make connections or just get an overview there exist the legacy programs 
Patchage, Catia, and for Pipewire specifically there is qpwgraph. FinallyThe program qjackctl can be used to start a JACK sound server. It has a nice graphical user
interface and can generate a .jackdrc file as well. |