On 12/28/2015 04:06 PM, Jonathan Joseph Chiarella wrote:
> Hello,
>
> As you develop the 2.0 version and set defaults I would like to argue
> the case for the use of non-flat volumes - in other words, change the
> default config file for pulseaudio (as part of the Gnome Shell
> desktop) at /etc/pulse/daemon.conf (flat-volumes = yes -> flat-volumes
> = no)
>
> The default behaviour changed to use flat volumes some years ago.
>
> This is disadvantageous for the user experience.
>
> 1. Flat volumes effectively render the master volume pointless.
> (A) Moving the slider down only lowers the volume of streams that
> were set at the same level that the master volume was.
> (B) If any stream moves above the master volume, the master volume
> moves up, but this is just cosmetic, since the master volume does not
> set any limits. The only effect is that moving streams altogether will
> now be changed and all streams move in tandem in different ways
> (C) If any new streams open at 100%, the master volume is set at
> 100% while old streams remain low, destroying any proportionality you
> would want to keep by just moving the master volume slider.
> (D) The master volume is not truly a master volume. Each individual
> audio output stream is actually an independent stream that controls
> the audio card directly and is irrelevant to whatever level the master
> volume is set.
>
> 2. Flat volumes do not behave like physical mixers, which are the
> source for the concept of and the source for the visual representation
> of a "master volume".
> (A) In a real mixer, or with flat volumes disabled, the master
> volume controls the audio card. Each stream remains always a
> proportional equal to or less than the volume. So if some programme
> outputs at 100%, it will be 100% of the master volume.
> (B) Moving the master volume will not ever affect the volumes of
> audio streams relative to one another.
> (C) The addition of new inputs will not affect the max output level
> set by the audio card. No unauthorized raising of master volume.
>
> 3. Accessibility and safety
> (A) If flat volumes are used, then any new stream (like System
> sounds, one that comes and goes) could open at 100%, raising the
> master volume, but more importantly it would output at max volume
> allowed by sound card. Since Tails is used often discreetly, the usage
> of headphones is to be expected. The shock of sudden jumps in volume
> is dangerous.
> (B) Since those who care or know about this and those hwo have it
> explained prefer non-flat volumes in the majority and since Tails is
> strict about its persistence, the flat-volumes default will
> inconvenience most users and they will not be able to configure it a
> persistent way (not even per-user through ~/.pulse)
>
> 4. User expectations and general preferences
> (A) The argument of "That's how Windows does it and Windows is
> widely used" is not an argument for a good user experience.
> (B) The previous argument is not true. Before Vista, Windows did
> not have flat volumes. It also lacked the integration of
> in-application volume sliders and stream volumes like many poorly
> integrated ALSA or Pulseaudio audio players on *nix.
> (C) Even post-Vista, Windows flat volumes do not behave like Pulse
> in flat volume mode. It is more like a hybrid of the two. So it is
> inappropriate to hold up Windows since it does not behave like
> Pulseaudio does.
> (D) The volume slider on some pairs of headsets behaves exactly
> like the true/traditional master volume concept.
> (E) Downstream of Debian is Ubuntu and its re-spins and
> derivatives. These overwhelmingly form the majority of desktop Linux
> installations and are the first experience most have with *nix on the
> desktop.
>
> There is a long discussion at reddit at
> <www.reddit.com/r/linux/comments/2rjia
> /horrible_decisions_flat_volumes_in_pulseaudio_a>
>
> The very problem described in the reddit original post was experienced
> often, I believe, by Chris Fisher of Jupiter Broadcasting (Linux
> Action Show etc) this month. He blamed KDE for not preventing it. I do
> not know what caused him to have his volume spikes, but I switched to
> non-flat years ago for because of this problem and I know that Chris
> Fisher's usual distro is Arch, which uses flat volumes. So I am
> guessing he takes flat volumes for granted or is unaware/forgot that
> non-flat volumes are a thing on desktops and is suffering from the
> same problem.
>
> Flat Volume PROS: default (but Tails changes defaults all the time) as
> advocated by Poettering and is somewhat similar to Windows Vista and
> post-Vista
> Flat Volume CONS: Reasons mentioned above.
>
> Using flat-volumes when users do not want them, in the worst case
> scenario, blows out their ears, causing damage.
>
> Using non-flat/normal volumes when users do not want them, in the
> worst case scenario, makes you unable to instantly make a given stream
> play at the absolute maximum volume of your sound card If stream TOTEM
> is 50% and Master Volume is 83%, then, in order to get TOTEM to play
> at the absolute maximum of the sound card, then you have to raise the
> Master volume on the panel or through media keys and also move up the
> slider in the TOTEM window.
>
> The urgency to raise the volume on TOTEM is outweighed by the need to
> prevent sudden alerts coming in and playing at the maximum volume of
> the sound card.
>
On 01/08/2016 05:31 PM, sajolida wrote:
> Jonathan CHIARELLA:
> Hello,
>
> Hi Jonathan, thanks for getting in touch with us.
>
> I'm sorry we didn't answer you before but we were all quite busy with
> the end of year, etc. I still didn't find time to analyze your proposal
> in depth. It's quite long and complex and I fear I'd have to spend
> several hours on it to understand it correctly.
>
> Still, to make my task a bit easier, could you maybe clarify what would
> make the context of Tails different from other GNOME installations to
> justify differing from the default? Or could your argumentation equally
> applies to all GNOME installations in general?
>
Thank you for replying and n worries on reply speed.
The arguments could apply to any installation. I do believe the
arguments against flat volume is even more applicable to Tails.
One of the arguments for Flat Volumes is that it avoids clipping in the
following scenario: Poorly designed media player has volume set low, to
be a proportion of the master volume which is high. Though the sound
card and the final audio output sent to ALSA are both well within
limits, the media player has already compressed the audio and already
applied clipping. This edge case is not relevant for Tails since no one
is using poorly designed media players yet also demanding high fidelity
in the output.
As said before, the likely scenario is someone using Tails in a cafe
with headphones. In this case, we should strive to avoid having system
sounds or new streams get created and jack up the master volume. A user
would set the master/sound card volume to the tolerable limit of the
headphones. If the loudest sound on my computer on my headphones is
tolerable at 80%, then I set my master volume in PulseAudio at 80% and
configure all applications to be a fraction of the master volume. In
other words, no app or stream, even at relative 100%, could possibly
make sound card output higher than 80% of its physical capacity.
Under flat volumes, the master volume loses this capacity to set a
maximum volume. At best, it sets a recommended starting volume for any
new output streams that appear.
As it is, Tails changes many default settings and this would just be one
more.
My recommendation applies to most installations of PulseAudio (except
for some possible DJ/mixing scenarios - but then you would be using JACK
and not PulseAudio), but it is especially relevant for the Tails user,
who may be using Tails in public to listen to important content and
probably using headphones. The unintentional broadcasting of content by
suddenly high volumes, the attention drawn, and the damage done to ears
with the headphones are things that we must avoid.
