See e.g. [this article on opensource.com](https://opensource.com/life/16/1/configuring-linux-for-music-recording-production). TLDR:
```bash
sudo apt-get linux-lowlatency jackd2
```
high priority (realtime) for e.g. [Reaper](/music/production/daw/reaper) and [Renoise](/music/production/daw/renoise).
```bash
sudo setcap 'cap_sys_nice=eip' /usr/local/bin/renoise-3.4.2 
sudo setcap 'cap_sys_nice=eip' /opt/REAPER/reaper
```
and CPU governor to `performance`:
```bash
echo -n performance | sudo tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
```
See [this FAQ on Pulseaudio and Jack](https://jackaudio.org/faq/pulseaudio_and_jack.html) ([[Pulseaudio]]
is the desktop Linux sound-server used by *everything except low latency audio apps*. We want
`jackd` to manage the audio hardware, and Pulseaudio to go the hardware via `jackd`.)

## limits.conf
```
 @audio - rtprio 90       # maximum realtime priority
 @audio - memlock unlimited  # maximum locked-in-memory address space (KB)
```
(source: [linuxaudio.org](https://wiki.linuxaudio.org/wiki/system_configuration#limitsconfaudioconf))

## Jack stuff
Use Cadence

### Old
We want to route ALSA to Pulseaudio, and Pulseaudio to Jack.
```bash
sudo apt-get install pulseaudio-module-jack
```
then `~/.config/pulse/default.pa:`
```
load-module module-native-protocol-unix
load-module module-jack-sink channels=2
load-module module-jack-source channels=2
load-module module-null-sink
load-module module-stream-restore
load-module module-rescue-streams
load-module module-always-sink
load-module module-suspend-on-idle
set-default-sink jack_out
set-default-source jack_in
```
and possibly in `~/.config/pulse/daemon.conf:`
```
default-sample-format = float32le
default-sample-rate = 48000
realtime-scheduling = yes
exit-idle-time = -1
```
and if using `qjackctl` as the launcher, in settings, add the following post-startup script
```
pactl load-module module-jack-sink channels=2; pactl load-module module-jack-source channels=2; pacmd set-default-sink jack_out
```
![qjackctl post startup options](qjackctl_options_poststartup_001.png)