Spatialized audio is sound processed to give the listener the
impression of a sound source within a three-dimensional environment.
This is a more realistic experience when listening to recorded sound than
stereo because stereo only varies across one axis, usually the x (horizontal)
axis.
In the past, binaural sound was the most common approach to
spatialization. The use of headphones takes advantage of the lack of
crosstalk and a fixed position between sound source (the speaker
driver) and the ear. Gradually, these factors are endowed upon
conventional loudspeakers through more sophisticated digital signal
processing.
The wave of multimedia computer content and equipment has increased the
use of stereo speakers in conjunction with microcomputers.
Additionally, the purchase of this equipment, and the current consumer
excitement surrounding the computer market, increases the awareness and desire
for quality audio content. Two speakers, one on either side of a
personal computer, carry the particular advantage of having the
listener sitting rather closely and in an equidistant position between
the speakers. The listener is probably also sitting down, therefore
moving infrequently. Fortunately, this typical multimedia configuration
probably comes as close to binaural sound using headphones as can be
expected from free field speakers, increasing the probability of
success for future spatialization systems.
Several intriguing uses for spatialized audio have been listed by the
Multimedia
Computing Group at Georgia Tech University:
Also, a
Surround Sound FAQ can be found at the MIT Press WWW server.
Next Section:
Spatial audio can be useful whenever a listener is
presented with multiple auditory streams, requires information about
the positions of events outside of the field of vision, or would
benefit from increased immersion in an environment. Possible
applications of spatial audio processing techniques include:
For further explanation of their work, see the Spatial
Audio Work in the Multimedia Computing Group WWW page, which includes
links to key references and samples of spatialized audio.
Future audio and Internet developments:
Perception-Based Compression (Perceptual Coding)