[pulseaudio-discuss] Per-app flat volume adjustment is highly unintuitive, if mathematically consistent.

[Finn Thain]

Lennart wrote:

> 
> Now, I must admit that this all is a bit hard to grasp. And thus not 
> exactly the definition of easy to use. We had a couple of discussions on 
> this very ML about this. So far noone came up with a way to fix this in 
> a way that would be completely convincing.

I can't claim to grasp it, but...
 
> I think the core problem is that it is impossible to figure out what the 
> user actually wants. When he increases a volume of a stream he might A) 
> want it a bit louder then whatever else is currently playing and would 
> be pissed off if the other stream would get louder at the same time or 
> B) want it a bit louder because everything that's playing is just too 
> silent and he would be pissed off if only one stream would get louder 
> and not all.

It seems to me that these problems would go away if you accept that 
boost/compression should not be a function of volume. (Use a seperate 
module!) If PA can't satisfy audiophiles, then PA will not earn a great 
reputation with the layman who trusts experts either.

Every sensible volume control I can think of is conceptually an 
attenuator, i.e. zero decibels at maximum (even if it is implemented as 
amplifier gain control internally). That's why a slider is appropriate as 
a GUI element here. (VLC player notwithstanding. I carefully leave it at 
100% and never touch it. The 400% upper bound is both non-intuitive, 
arbitrary and likely to distort.)

So, if as you claim, the user "might A) want it a bit louder then whatever 
else is currently playing and would be pissed off if the other stream 
would get louder at the same time", I think that user has probably never 
used a volume control or mixer (i.e. an attenuator). It doesn't make sense 
(in my mind) to optimise for this unusual situation.

Finn