My first three-dimensional (3D) sound experiment was done in 1976. I was testing a new speaker cabinet in a dormitory corridor. After playing the recorded sound of a landing jet and noticing several people looking outside the windows for the low-flying plane, I decided the cabinet was ready for my guitar chops.
This book is about making the listener visualize or position in space what he or she hears: travel with the solo violinist, experience different environments, or have the auditory impression of seeing different places. The author gives ample and easy-to-understand definitions of such concepts as a virtual sound source, which is to sound what a virtual image is to light. He draws an interesting parallel with current ecology trends that look at fatigue in users of computer display systems. Audio, with noise and distortion, can be considered another source of fatigue in our stressed environments, and 3D sound technology may help create a more positive working environment. Would we build better cars if the workers felt they were in a relaxing place? Would we have even fewer plane crashes if sound technology could help communication in a pilot’s cockpit?
The advent of digital sound recording and playback systems in the consumer market helped develop digital signal processing (DSP) technology and digital sound treatment, which can be found in numerous commercial applications, so everyone can “experience new and exciting dimensions of cyber-audio space,” which in the past would have been restricted to military and lab applications.
Starting with chapter 2, the author introduces technical aspects of 3D sound, such as lateralization and our ability to distinguish sound sources above and below our heads. By reading the book and looking at the impressive references, it becomes obvious that a lot of experimental work has been done in order to understand and measure the capabilities, as well as the limits, of the human auditory system. Numerous drawings, charts, and diagrams explain the work done in prior studies.
The author then looks at different implementations of 3D sound systems, from capture to playback. A special section covers the benefits of using DSP technology to implement filtering and positioning algorithms. Reverberation techniques are also covered. The next chapter covers 3D sound applications; the author briefly mentions the MIDI standard. He also presents several commercially available sound boards and sound systems, and discusses current work in the area of computer workstations. He concludes with a large resource listing, ranging from hard-to-find papers and studies to easy-to-browse and online documents.
This interesting book is for everyone who wants a good, not-too-technical introduction to 3D sound. Different aspects and applications are presented, an extensive bibliography is proposed, and numerous graphs and industrial examples illustrate the actual technology. We can expect a lot from 3D sound in the near future.