ALSA
Overview
The Advanced Linux Sound Architecture (ALSA) provides audio and MIDI functionality to the Linux operating system.
Use ALSA on with Applications requiring PulseAudio
Using applications which require PuleAudio on systems which only have ALSA installed can be accomplished through the use of apulse which is a pulse emulator for ALSA.
Install apulse
Install apulse from the AUR using a your preferred package manager or the command:
pamac build apulse
It is built from source so it may take some time to install. Once it is done, create a basic config file using the command:
cp /usr/share/apulse/asoundrc.sample ~/.asoundrc
Using apulse
Using apulse is a simple typing apulse <program> in a terminal. For example:
apulse /usr/lib/firefox/firefox
If all is working, you should now have sound in Firefox without needing pulseaudio
Selecting the Primary Audio Device
If your system keeps on using the wrong device (HDMI instead of PCH or vica versa for example), you can force ALSA to use the correct device. Start by getting a list of your audio devices with the command:
cat /proc/asound/cards
Note the number of the sound device that you want to make the primary. Then using a text editor, put the following into /etc/asound.conf (You may need to create /etc/asound.conf if it doesn't already exist).
defaults.pcm.card 1 defaults.ctl.card 1
Replace 1 in the above example with the number you noted down above.