Applications - Soundscape Ecology: Principles, Patterns, Methods and Applications - page 287

Sonification concurs in the complexity of the sonic offerings of this modern
world, and its impact on the environment will increase in the future together with
the “dematerialization” of modern devices.
Sound is a source of information. Voice, song, and calls are semiotic objects
extensively used in the real world by human and nonhuman animals. In a techno-
logical world the production of sounds is used as an auditory display that returns
non-speech sounds to warn, alarm, indicators of status, etc. (Walker and Kramer
2005 ).
There are several types of auditory display:
Alert and notification
The sound is used to indicate that an event is to happen; the long beep of a
microwave is an example. This sound does not indicate if the food is cooked but
simply that the time topic is expired. The same is for the telephone ring that does not
indicate who is calling, although actually we have ringtones in cell phones that can
be personalized with the single number.
Cautions and warnings
It refers to sound that are linked with a specific event, such as fire alarm signals, or
the sound that precedes announcements in airports.
There are two basic approach to increase the efficiency of signaling: auditory
icons and earcons.
The auditory icons are equivalent to visual icons that are symbols which depict
objects, such as the image of a deer along a road to alert about possible crossings by
wild ungulates. Icons are extensively used in the computer language and in the
Internet. So an auditory icon is a sound that copies the sound of the object
represented, perhaps a typewriter.
Earcone is a more sophisticated representation of an event, so when a file is
moved into the desktop trash the sound is that of crumpled paper. The file deletion
may be represented by a plain beep that in a second is degraded in terms of loudness
and pitch that metaphorically represent the vanishing of a file.
Audification is the direct translation of a data waveform into sounds. This
process requires that the transformation is made along the human audible spectrum
with possibilities to increase or decrease the time. One example is represented by
seismic data: in this way is possible to distinguish the variations of strata complex-
ity in oil exploration or in earthquake events. In one experiment listeners were able
to separate more than 90 % of the underground explosions from earthquake events
(Speeth 1961 ). Some waves when transformed in a sonic format can be easily
distinguished from the background noise, and auditory expectation can be produced
rapidly; for instance, 24 h of data can be represented in 5 min of acoustic output.
The auditory display is considered a form of applied auditory perception
(Walker and Kramer 2005 ).
Between the different task of the auditory display perception is one of the first
objectives. The listener must hear the sound and the changes of its parameters.
Perception requires an integration between sound attributes, the environment, and
the listener. Especially when we are in a source environment and where competitive