ALSA: Dogmatism and Empiriokritizismus

igorzwx · Yesterday 23:01:56

The official ALSA documentation is here: _https://www.alsa-project.org/wiki/Asoundrc

ALSA: Outdated documentation
_https://alsa.opensrc.org/Asoundrc#Changing_things
Asoundrc: Changing things
Most programs require a restart to reread .asoundrc or asound.conf! This includes desktop environment audio daemons, such as PulseAudio. For most changes to .asoundrc you will need to restart the sound server (ie. sudo /etc/init.d/alsa-utils restart) for the changes to take effect.

This chapter was deprecated and removed from the official ALSA documentation about 15 years ago (or more). However, the true believers still believe that it is necessary to reload ALSA "for the changes [in .asoundrc] to take effect".

If you see a "buffalo" sign on an elephant's cage, do not trust your eyes.
Kozma Prutkov, Fruits of Reflection (1853-1854)

To believe in a dogma, one should not trust his senses and his ability to think.

EDIT:

greenjeans wrote:

2025-09-22 15:51:04
I think I would start by making a super simple .asoundrc and going from there...
If that works, a simple script that offers a dialog where you choose either 0, 1, or 2, and it seds the change and re-starts alsa, would allow you to change during session.
_https://dev1galaxy.org/viewtopic.php?pid=58157#p58157

ralph.ronnquist wrote:

Yes, and one thing that is confusing with ALSA is that programs typically loads the sound configuration only once, early during startup. Therefore such a change to the configuration only takes effect for programs that are started after the change.
There is a way to make a configuration have a dynamic part, to be automatically reloaded upon every sink (or source) creation instead, but then we are entering a deeper level of understanding of ALSA configuration structure and elements which most people rather wish to avoid.

It is so "technical", that it is almost incomprehensible.

Last edited by igorzwx (Today 01:13:56)

greenjeans · Yesterday 23:37:05

Off your meds again Igor?

ralph.ronnquist · Yesterday 23:57:49

Could we keep to technical discussions please.

ralph.ronnquist · Today 00:16:37

I'm not sure what you take issue with... perhaps just that documentation on the web is old?

Otherwise I think one of the confusing aspects of ALSA configuration changes is that in general any program that use the audio system will end up loading an instantiating a configuration structure internally only once, when it starts. Therefore, such programs need restart after a change to the configuration source files, which include the user's .asoundrc file.

Though, a program may of course have been made to reload the configuration, and in that case such a program will do so as programmed and then rebuild the internal configuration structure from that on file.

I would suggest that old and bad documentation can only be remedied by writing new and better documentation; grumbling about what's existing and discussing it's badness is just waste of time.

igorzwx · Today 00:30:24

It was about a technical problem how to toggle ALSA configs with a script.

The main principle of ALSA design is a sort of "hot-plug".
Today, you do not need to reload ALSA, if you change .asoundrc
Though a media player may (or may not) need to be re-started.

The problem is that ALSA is poorly documented, and, therefore, one has to use the method of trial and error to find the correct solution. However, what is correct today might be wrong tomorrow.

To foresee changes in the "advanced sound system", one may need "a deeper level of understanding of ALSA", or a sort of esoteric knowledge for navigating uncertainty.

ALSA in user space is a sort of software mixer with plugins, such as dmix, dsnoop, and the like. Many years ago, ALSA was so buggy that it was necessary to reload ALSA to enable changes in .asoundrc. Today, to enable dmix or other plugin in .asoundrc, you do not need to reload ALSA.

In 2008, it was necessary to reload ALSA to enable dmix. This problem was fixed in 2009 (or 2010) in a new version of ALSA. In 2010, Ubuntu users were advised to recompile ALSA to fix sound problems, although it was enough to remove pulseaudio. In 2010, Ubuntu users asked questions like this: "Could I remove ALSA, and use PulseAudio instead?" Today, many "computer scientists" firmly believe that Fedora Linux has PipeWire instead of ALSA. Those modern "computer scientists" have the gift of faith in the sense that they do not trust their senses and their ability to think. They have a special, extraordinary trust in PipeWire's promises and a sort of "supernatural ability to believe in the unseen and to act on spiritual truths despite physical evidence to the contrary".

...some audio applications keep the ALSA PCM device open, even when they are not actively streaming any audio, and so it is necessary to close each application before any other can use the device...
ALSA provides a solution to this for hardware cards with the "dmix" plugin. That plugin allows multiple open connections, mixes the streams together, then sends the result as a single stream to the hardware device.
_https://github-wiki-see.page/m/Arkq/bluez-alsa/wiki/Using-bluealsa-with-dmix

dmix is needed to make ALSA usable.

When #Software mixing [dmix] is enabled, ALSA is forced to resample everything to the same frequency (48 kHz by default when supported). By default, it will try to use the speexrate converter to do so, and fallback to low-quality linear interpolation if it is not available. Thus, if you are getting poor sound quality due to bad resampling, the problem can be solved by simply installing the alsa-plugins package.
_https://wiki.archlinux.org/title/Advanced_Linux_Sound_Architecture#High_quality_resampling

The speexrate converter is also crappy.

In 2008, Ubuntu was infected with PulseAudio which was a replacement for dmix and the Enlightened Sound Daemon (ESD or EsounD) _https://en.wikipedia.org/wiki/Enlightened_Sound_Daemon
PulseAudio was very advanced, but buggy and unusable. ESD was not so buggy. It was usable, and, therefore, it was deprecated. However, it was still available, and the standard solution for sound problems was to remove PulseAudio and install ESD.

In 2008, dmix was extremely buggy (and ALSA resamplers have always been crappy). The sound quality was really horrible with dmix. This problem was fixed in 2010 with the fftrate ALSA plugin (and with ALSA update).

ALSA was designed as a universal solution to all problems, but it was so buggy that it was decided to create pulseaudio as a truly advanced solution to all problems. Pipewire was created for a similar reason.

Today ALSA is not so buggy and even usable, if it is correctly configured.

Last edited by igorzwx (Today 19:07:51)

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#1 Yesterday 23:01:56

ALSA: Dogmatism and Empiriokritizismus

#2 Yesterday 23:37:05

Re: ALSA: Dogmatism and Empiriokritizismus

#3 Yesterday 23:57:49

Re: ALSA: Dogmatism and Empiriokritizismus

#4 Today 00:16:37

Re: ALSA: Dogmatism and Empiriokritizismus

#5 Today 00:30:24

Re: ALSA: Dogmatism and Empiriokritizismus

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