The audio interface being used is a Native Instruments Komplete Audio 1
The distribution being used is Fedora 32
https://www.native-instruments.com/en/komplete-audio-1-quickstart/
- USB - Connected to computer
- IN1 - Disconnected - Gain set to zero
- IN2 - Connect guitar here - Gain set to zero (manage it in Guitarx)
- Mode switch - Set to
INSTfor guitar - 48V Phantom Power switch - Off, this is only used for EC Microphones
- Input / Host knob - Dial all the way to host
- Vol Jack - Connect headphones here and adjust volume with front knob (set to zero to begin and wind it up)
- Top Vol knob - Used for RCA out, set to zero if not using
Fedora natively packages everything you need
- The JACK daemon and related tools are used for managing the inputs
- Guitarix is the virtual amp we are using
- Audacity is used for recording and audio editing
sudo dnf install guitarix audacity jack-audio-connection-kit qjackctl \
alsa-plugins-jack pulseaudio-module-jack jack_capture
NOTE: The jackd2 package will create the required limits file in /etc/security/limits.d
sudo apt update
sudo apt install jackd2 pulseaudio-module-jack qjackctl
sudo apt install audacity guitarix
sudo usermod -a -G audio "$USER"
sudo reboot
Starting JACK
jack_control start
Due to audio being latency sensitive, JACK requires real time scheduling.
This requires privileges due to the ability for an application to abuse it and negatively impact the system.
Fortunately it can be permitted per user/group via PAM.
You do not require a real time Kernel
The documentation for what you need to do is here: https://jackaudio.org/faq/linux_rt_config.html
I discovered the Fedora package already handled this though, all that is required is to add ourselves to a new group it created and re-log (or run su - $USER in the terminal where you will run JACK)
sudo usermod -a -G jackuser $USER
- Connect everything to your Audio Interface
- Run
qjackctl - Click Setup > Settings > Advanced > Set your Output and Input devices to your Audio Interface
- Click Setup > Settings > Parameters > Set Sample Rate: 48000, Frames/Period: 256, Periods/Buffer: 2
- Apply all settings and close Setup window
- Click Start in the main
qjackctlwindow - Run
guitarix - In the main
qjackctlwindow click Graph, you should see your Audio Interface inputs/outputs and the Guitarx components (amp and effects), wire them together:
In my case it went:
system capture_2 > gx_head_amp in_0
gx_head_amp out_0 > gx_head_fx in_0
gx_head_fx out_0 > system playback_1
gx_head_fx out_1 > system playback_2
Plug in and play!