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LPC: Linux audio: it's a mess

Posted Sep 19, 2008 21:22 UTC (Fri) by rahvin (subscriber, #16953)
In reply to: LPC: Linux audio: it's a mess by ewan
Parent article: LPC: Linux audio: it's a mess

I understand your point, but as a user if I want to control a feature of an application I expect that control to be in the application, not some central sound daemon. I would think the default user behavior when looking to control the sound of an application would look first in that application not at some upper level. I agree with the poster you are responding to, the problem with browser sound is with the plugin/browser, not some central sound control. I can't tell you how often I right click on some flash application thinking there will be a volume control in the context menu. There should be a control in that context menu, that there isn't is a problem with the application.

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Posted Sep 20, 2008 3:41 UTC (Sat) by drag (subscriber, #31333) [Link]

Well it's confusing. I'll illustrate:

Say your using something like xmms or other application that has it's own volume control.

So you have the Gnome volume control stuff. It's the icon in your task bar and the mixer control stuff in your applications menu. This provides a 'sanatized' way to interact with volume controls. So you can have that nice little icon and the sound mixer buttons on your multimedia keyboard and whatnot.

Then you have the low-level Alsamixer interface. This reflects the actual hardware capabilities of your sound card. When your mucking around with the PCM slider your interacting with the sound card's hardware. It's confusing to use and each sound card has different capabilities so it's a UI that will change depending on what sound card you have.

Then you have your 3rd mixer interface at the application level.

Then on top of that people using desktops will have another volume control on their speakers. So that makes 4 different volume controls that interact with the sound card. Different applications will go through the Gnome stuff, interact with alsamixer directly, or have their own controls. Depending on how the application is configured it can interact with controls differently at different times. (ie, some apps can be configured to use OSS vs Alsa vs ESD vs artsd vs etc)

This is confusing.

Now say your trying to do a voice recording or interact with a VoIP application. Things get _very_ confusing.

With PA you have the master controls and the application controls in the same spot. Then that eliminates the requirements for mixing controls in your browser, file manager, your terminal's beeping, etc etc.

So this _should_ lower the mixing controls down to 2 on the software side. Alsa stuff should setup correctly, but it won't be for the significant number of people. So you still need alsamixer for getting the "baseline" set. But after that you should only need to deal with one interface.

It's still very goofy, but not as goofy.

LPC: Linux audio: it's a mess

Posted Sep 22, 2008 2:11 UTC (Mon) by elanthis (guest, #6227) [Link]

Less controls is not the right solution.

Sometimes you want the same thing in multiple places to help usability.
Where you might think to look first isn't where someone else might look
first. It's pretty clear that some people are going to try to adjust the
sound volume on the thing making the sound (the individual app) and not the
mixer control on the panel.

However, PA is what makes that possible. Note that I said "the same thing"
in multiple places. The volume widget in the app should modify the volume
of the PA stream, and be reflected in the desktop mixer utility, and vice
versa. Without things like PA, this becomes much harder. It's not even
possible without a lot of crap being shoved into the drivers.

LPC: Linux audio: it's a mess

Posted Sep 22, 2008 16:55 UTC (Mon) by drag (subscriber, #31333) [Link]

> Sometimes you want the same thing in multiple places to help usability.

Not when those multiple things do very different and conflicting actions in very very non-obvious manners.

If you have:
1. Mozilla Browser volume control and mute.
2. Gnome Volume Control and mute (that ties into your volume icon and multimedia buttons)
4. Low-level Alsa volume control and mute.
5. Speaker volume control and power.

Now you open up a youtube video. You get no audio.

Tell me, with certainty, which control, or combinations of controls, you will have to use to make the sound audible.

There is a difference between having 3-5 different places to control volume vs having 3-5 different controls you have to use.

LPC: Linux audio: it's a mess

Posted Sep 20, 2008 11:27 UTC (Sat) by dirtyepic (subscriber, #30178) [Link]

Well, when I want to control the sounds coming out of my laptop, I would generally head to the place where the sound controls are, not in every application on the system that has any kind of capability of producing noise. Do you really think having dozens of apps, each with their own independent volume control, is a good idea? It's stuff like that, everyone going off and implementing their own incompatible audio systems, that helped get us into this mess in the first place.