Session Title:	3D and Multichannel Audio
Session Chair:	Sean Olive, Harman International, Northridge, California, USA
Participants:	Brian McDowell, Microsoft, Redmond, Washington, USA; Theodore Tanner, Spatializer Audio Laboratories, Mountainview, California, USA; Jerry Bauck, Cooper-Bauck Corporation, Tempe, Arizona, USA; Tomlinson Holman, THM Corporation, Los Angeles, California, USA; John Norris, Harman International, Northridge, California, USA, Mike Smythe, DTS, Westlake Village, California, USA
Tomlinson Holman: Monitoring Sound in the One-Person Environment: With the growth of personal computers as display devices for media has come the need to monitor sound accompanying images on these systems. Many of the same parameters that constitute the capabilities of large-scale systems also need to be addressed in small-scale ones in order to produce similar experiences of the program material. These include frequency range and response over the range, dynamic range, and stereo imaging capabilities. In addition, some new problems also arise, such as those brought about by being so close to the loudspeakers, and the difficult acoustical environment faced by the loudspeakers. Several methods are described that make the desktop environment useful in making professional judgments of sound usually reserved for large-scale calibrated monitoring systems. Theodore Tanner Jr.: With the advent of data transmission standards such as AC-3 (Dolby DigitalTM) and MPEG there are many systems that include these features and the ancillary features such as discrete channel surround. Three-dimensional sound has become a viable solution to replicate the sound field produced by these multi-channel surround sound formats. Many companies that have provided solutions for duplicating the multi-channel sound field by displaying the audio over two speakers and by applying various techniques have duplicated a localized point source for the discrete left and right surround speakers. This presentation will discuss a criteria and means for evaluating said virtual imaging systems. Hypothesis as to why and how we perceive localized audio over loudspeakers and the pitfalls thereof will be discussed. Jerry Bauck: A review of 3D audio principles will be presented, up to and including the principle of layout reformatters as discussed in a paper by the author in the 1996 September Journal of the Audio Engineering Society. Layout reformatters offer the possibility of correct conversions between various channel-loudspeaker combinations, affording a level of compatibility between competing multi-channel systems and with variable end-user layouts. Also offered is a simple explanation of why panning of phantom images to the sides of a listener using side loudspeakers is largely ineffective. The following questions outline what will be addressed in this session. What are the psychoacoustic principles that are used to make 3D audio possible over loudspeakers and headphones? In practice, what are the performance limitations or restrictions with 3D audio played over headphones and loudspeakers? Are there any solutions to overcoming these restrictions? There are several different proposals for delivering multichannel audio via CD and DVD. Which ones are most viable from a technical, economic and aesthetic viewpoint and why? How do the physical acoustics of the loudspeakers and room influence the reproduction of 3D and multichannel audio? Are there methods of optimizing the playback system for better quality reproduction? Are there any solutions to enhancing or creating multiple "sweet spot" listening locations for 3D audio played through loudspeakers? What are the current and future "killer" applications for 3D and multichannel audio on the computer desktop? What are the hardware/software requirements in order to produce and playback high quality 3D and multichannel audio on the computer desktop ? Are there scaleable solutions for people who don't all the hardware/software and how well do they work? What are the features and performance specifications of Microsoft's Direct3DSound API? How can we deliver 3D and multichannel audio over the internet to ensure it maintains a high standard of quality? What are the performance requirements? What benchmarks and standards, if any, are in place to scientifically evaluate the objective and subjective performance of 3D and multichannel technologies? Are current methodologies adequate? There is currently little or no 3D or multichannel content for music. What are the marketing and economic forces that are driving or prohibiting the commercialization of 3D and multichannel audio? Would the record industry prefer the status quo?

Biographies:

Sean E. Olive, Brian McDowell, Theodore Tanner Jr., Jerry Bauck, John W. Norris

Sean E. Olive SEAN OLIVE received a Bachelor of Music in 1982 from the University of Toronto, where he studied piano. In 1986 he graduated from the Tonmeister program at McGill University in Montreal, Quebec receiving a Master's degree in Sound Recording. From May 1985 to March 1993 he was a research scientist at the Acoustics and Signal Processing Group at the National Research Council, located in Ottawa. In March 1993, Mr. Olive joined the R&D Group of Harman International in Northridge, CA, as manager of subjective evaluation. His responsibilities include overseeing subjective testing of consumer, professional and computer/automotive audio products within all Harman companies worldwide. Mr. Olive has chaired and presented several papers at AES conventions, conferences, and workshops related to research on the perception and measurement of sound reproduction. He has published several of these papers in the AES Journal, for which two received AES Publication Awards in 1990 and 1995. In 1996 Sean received the AES Fellowship Award. Mr. Olive is a member of the AES Working Group on Listening Tests, and is on the Executive Committee of the Los Angeles section. Brian McDowell Brian McDowell has been developing proprietary audio technology at Microsoft for the last 5 years. He recently moved into the DirectX team where he is now Program Manager for DirectSound. Brian is currently actively involved in developing the WDM Audio driver model for upcoming releases of Windows and Windows NT operating systems as wells as the new DirectMusic technology. In his ever-so-rare spare time, Brian is also a musician and song writer. Theodore Tanner, Jr. Theodore Tanner, Jr. is currently the Vice President of Engineering at Spatializer Audio Laboratories, Inc. where he directs and participates in the research and development of the companies DSP efforts. He currently sits on the Technical Review Committee for the International Conference on Signal Processing Applications and Technology. He is also the Vice Chairperson for the San Francisco chapter of the AES. Tanner holds an MS in Audio Engineering from the University of Miami. Prior to joining Spatializer, he held DSP engineering positions at National Semiconductor, Crystal River Engineering and Digidesign. He is a member of the AES,IEEE, and ASA. Jerry Bauck JERRY BAUCK earned a B.S. from Kansas State University and M.S. and Ph.D. degrees from the University of Illinois, all in Electrical Engineering. His Ph.D. work was in space-based synthetic aperture radar. He has worked for Motorola in radar, acoustics, and signal processing and has consulted for various companies. He began early 3D audio studies in 1978 with Duane Cooper. Dr. Bauck is president of Cooper Bauck Corporation, an audio engineering and Transaural licensing concern. John W. Norris JOHN NORRIS completed his D.Phil (Ph.D.) in Mathematics at the University of Oxford in 1987. Since January 1993, he has been employed by Harman International. Presently he is helping develop Harman's VMAx virtual sound positioning technology. He has also worked on an active control system for noise and vibration cancellation. Before taking up his present position, he held teaching and postdoctoral positions at the University of Oxford and University of Birmingham in England. His areas of research interest include signal processing, nonlinear dynamical systems, and acoustics.

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