I was entirely happy with alsa and still don't know of any use-case I have that's better served by the more fragile, more resource-hungry PulseAudio. I assume it's useful to someone.
I keep seeing this argument in this thread and quite frankly I'm dumbfounded. Last time I've had this issue was more than a decade ago on FreeBSD and it was solved by tweaking my OSS config to enable multiple channels. I've never, ever had this issue with Alsa. And I'm not a fan of Alsa either, PA just managed to be even more opaque and less reliable in my experience.
Now, it's just anecdotic evidence of course but basic audio mixing is not exactly rocket science, you shouldn't need something as convoluted as PulseAudio to get it right. I mean, what the hell: https://gavv.github.io/blog/pulseaudio-under-the-hood/diagra...
Some power users might need these additional features, I don't. I wouldn't mind having all of that if the basics just worked reliably but they don't.
These days disabling PA is my go-to first step while troubleshooting audio issues on linux and more often than not I don't have to go to step #2.
ALSA refused to do mixing in software for some time. Maybe it still doesn't do it, I don't know. So if you had a hardware sound card that would do mixing, you could play multiple channels with ALSA, but if you didn't, you were SOL.
Alsa has had dmix for quite some time. The thing was that until something like a decade ago it had to be manually enabled via a .asoundrc edit. These days Alsa will enable it automatically on any device known to not have a hardware mixer.
Maybe so, but I did try to fix it without resorting to a hardware sound card and couldn't at the time. IIRC the syntax of the ALSA configuration files was particularly arcane.
Also spoken confidently like someone that never tried to play sound in two applications at once.
This has worked well in ALSA for years now. Now, ALSA won't let you set the volume of each application separately, but most applications have their own volume control for that anyway.
And you'll never have to deal with the application's volume Pulse's volume for that source disagreeing, and scratching your head as to why even though you set the volume to max, it isn't getting very loud. To be fair, maybe this has been entirely solved; the last time I used Pulse was ~5 years ago[0], so I might be a bit out of date. But not more out-of-date than the claim that ALSA can't play sound in two applications at once!
[0]: I don't have anything against Pulse, I just don't see the point in installing it. What does adding it to my stack get me?
Another "lovely" thing about PA is that will allow the loudest of the "apps" (groan) to ramp up the master control (do not recall the "feature" name right now).
Do wonder how much future hearing loss it has created by sudden spikes in volume...
You are talking about "flat-volumes", I also recommend disabling it. Even forgetting the issue you mentionned, it just makes volumes harder to handle and reason about.
I wonder if they would have ever implemented this "feature" if it wasn't the default (and only) behavior on Windows...
Oh! When all of the GUIs say sound is at max, but it's either really quiet or silent, and it turns out that it's because even though the PA volume is up, somehow ALSA (which PA ultimately uses on the backend) got muted. But this is a PA box, so you have no GUI tools to set the ALSA volume!
This has worked reliably in ALSA before it has worked reliably in PulseAudio (and, in fact, way before PulseAudio received any meaningful adoption, when Fedora enrolled everyone in PA's beta testing).
Well, maybe in the later days, but there was a long time when it didn't work well at all. I remember having to mess with the ALSA configuration to make it work. And then you also had apps which only supported OSS and getting them to work together with ALSA was an additional pain.
The reason for that was that while dmix was available for a long time, it was not enabled automatically on hardware without hardware mixing. More recent versions will silently (heh) enable it on hardware thats known to not have hardware mixing.
What later days? Software mixing worked fine in ALSA in 2004-2005, and OSS emulation had been working reliably way before that. The first PulseAudio release was in 2004, and it wasn't adopted by Fedora until way, way later.
At the same time, all other apps are at a level that won't cause painful audio to hit your ears.
If you trust VLC and you trust the video file you're watching, then turn the master audio back up during the loud "Universal Pictures" intro or whatever is an equivalent introductory sound at the beginning of the movie you're about to watch.
On my chromebook, there are two volume buttons and one mute button that are by far the most convenient way to adjust (master) audio for such a situation. So you turn down for random browsing and turn up for watching movies or whatever.
Btw-- those are almost certainly the controls someone would use to turn down or mute the sound of that horrible website audio listed above. In such a case the fact that pulse can give you an app volume for Chrome doesn't help anything-- for example, the user who adjusted Pulse app volume down to avoid pain will need to adjust it back up when watching a movie on Youtube for the same reason you mentioned. But they can't adjust the app volume with the keyboard controls. So to make use of that feature forces a more complicated UI that takes longer to use.
Then you tell your movie player to just make it louder, discarding that beautiful dynamic range. If you're paying close enough attention to the movie to care about the loss of dynamic range, then you probably aren't doing something else that might make sound, so you won't mind turning the master volume up.
So how do you ensure that one tab wasn't much louder than the other?
In this case, it doesn't make much sense to treat the browser as a single application, but each site as one (does Chrome export each tab as a separate source to PA? IDK, I haven't checked). And, I can't think of a single thing that I actually want producing sound (and don't mind just muting) from my web browser that doesn't have its own volume control.
