Re: [Usability] New Sound Preferences and Volume Control

[Martin Soto <soto informatik uni-kl de>]

Hello all:

On Mon, 2008-12-08 at 06:03 -0500, Philip Ganchev wrote:
...

After reading this discussion, I have the strong impression that we are
trying to use sound volume control to solve problems that should be
handled otherwise. Let's see:

> 1. Giving a presentation - mute IM, email, battery(?) notifications

A presentation mode should block much more than just sound: it should
block notifications completely, so that you don't get dialog boxes or
notification bubbles either. It may also block programs running in the
background such as the file indexer. For this reason, this should be
handled at a completely different level, e.g., by providing an API for
notifications that makes it possible for certain applications to block
them. This should also happen automatically, by the way: the user
shouldn't be expected to set the current profile, but the profile should
be activated automatically by the presentation program when it moves to
fullscreen mode.

> 2. Preparing a presentation - notify at normal volume

This is the default behavior and applies to most other situations.

> 3. Working quietly - quiet notifications so as not to startle user

The purpose of notifications is to be noticeable. What this means to me
is that they should be clearly louder than whatever background sound
(music, movie, etc) you're currently playing. Alternatively, they could
just temporarily turn down the volume of the background sound. By the
way, if a notification can be safely ignored, it probably should be
removed, anyway.

> 4. Watching a movie with friends (or playing music at a party) - mute
> (or quiet) IM and email notifications

Once again, such an activity should put the system in something similar
to presentation mode. I really wonder if there's any difference at all.
This means, block notifications instead of just blocking the sound of
notifications.

> 5. Casually watching a movie (or listening to music) - IM, email(?)
> louder than movie.

Music listening and movie watching are different use cases. Music can be
listened to in the background, whereas movies typically require
concentration. Of course, there are people who like to have movies or TV
running "in the background" while doing other tasks, and in this case,
movies should be handled just like background music. I would say, this
could be easily handled by putting the system in "presentation mode"
when the music or movie player is running in fullscreen mode, and
handling it as background otherwise.

> 6. User is away from the computer - louder notifications

This can be detected automatically in many cases through the screen
saver.

> Thinking about such cases will help us create a default sound profile
> that works correctly in most cases. From the above cases, the user
> only has to configure the movie and music behavior (4 and 5). In all
> the other cases, we can guess the relative importance of sounds from
> different apps, and our guess is likely to be correct.

What I conclude from the previous analysis is that the behavior can be
determined automatically by just knowing what the *type* of a sound is,
and if you are in presentation mode or not. I see three main sound
types:

1. Multimedia: music or video soundtrack.
2. Non-critical notifications: sounds used to provide feedback for UI
actions (click when you press a button) or to inform of non-critical
events (a new email arrived).
3. Critical notifications: sounds used to alert the user about critical
conditions (battery is almost empty, your processor is so hot that it
will burn in 30 seconds, your boss/girlfriend is calling and she will
fire you/put your things on the street if you don't answer right now...)

This leaves us with six possible combinations:

In normal mode:
- Play type 1 at the volume level set explicitly by the user.
- Play type 2 in such a way that it is audible (but not startling!) over
whatever is playing in the background.
- Play type 3 in such a way that is clearly noticeable. This probably
implies temporarily turning down types 1 and 2.

In presentation/multimedia mode:
- Play type 1 at the volume level set explicitly by the user.
- Don't play type 2.
- Play type 3 in such a way that is in clearly noticeable. This probably
implies temporarily turning down type 1.

We may consider a third, "away" mode. But I don't know if it's really
needed. It would be like normal node, by making type 3 eventually
louder.

As a result, it looks to me that we could provide an appropriate
behavior for a large percent of users and use cases without having to
ask them to micromanage volume. The interface is reduced to a single
volume slider. The rest is handled appropriately and automatically.

By the way, I don't see a need to control the volume of multimedia
applications separately. If you think of it, unless you are a multimedia
freak who enjoys playing five videos simultaneously to show the power of
his processor, you don't want to play more than one think at a time.
Either you have some music or you have a movie running, and that's it.
This means that a single slider for multimedia volume should suffice.

Cheers,

M. S.