Audio on The Internet

Spatialized Audio

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:

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.

Also, a Surround Sound FAQ can be found at the MIT Press WWW server.

Next Section:
Future audio and Internet developments: Perception-Based Compression (Perceptual Coding)

Audio on The Internet