Matsushita Develops 3-D Sound Reproduction Technology for Mobile Devices
Matsushita Electric Industrial Co., Ltd. (hereafter referred to as MEI), best known for its Panasonic brand of consumer electronics and digital communication products, has announced today that it has developed the “Hypersurround Sound System” (HSS), a high-fidelity surround sound reproduction technology that will enable reproduction of three-dimensional sound fields on compact / mobile electronic equipment, and requiring only a small computational load and low power consumption.
Products such as notebook PC or portable audio player incorporating this technology will offer an unprecedented style of listening, enabling listeners using headphones with portable audio equipment to enjoy natural and expansive sound fields, just as if they were actually present in an acoustic studio or a concert hall. The technology will minimize the fatigue often associated with using headphones for an extended period.
HSS technology calculates various numerical values related to the acoustic
transfer space between a sound source and the human ear (known as Head-Related Transfer Function, or HRTF) rapidly and accurately, and extracts genuine acoustic characteristics for accurate localization of sound images. The development of this technology has reduced the total acoustic data capacity required to assimilate human head configuration to 1/4 that of conventional volume, thereby leading to a substantial reduction in energy consumption.
The technology also calculates HRTF values that match every angle of reflected sound in an acoustic studio or concert hall, allowing for a realistic, natural and dynamic sound quality that will not tire the listeners even when wearing headphones for extended periods.
As the technology is capable of analyzing efficiently fluctuations in HRTF values stemming from individual differences in head configuration, the analysis result can be further developed to obtain HRTF values that have a more general utility, based on statistical figures.
The development of HSS was made possible by the following three core technologies:
(1) Digital HRTF simulation technology using high-precision laser-scanned human head modeling and the boundary element analysis method. (Detailed measurement of the human ear shape was carried out with support from the Agency of Industrial Science and Technology of Japan.)
(2) Acoustic reciprocity analysis technology that enables ultra high-speed calculation of omni-directional acoustic characteristics from a sound source set from the human ear.
(3) Human head morphing technology based on mean and deviation values of head measurement, enabling fine adjustment of head configuration.
With conventional surround sound reproduction technology, HRTF values were measured from the head of a dummy or an actual person. In such cases, HRTF values included interferences attributed to microphone and speaker characteristics, as well as to the influence of sounds reflected from fixed or mobile equipment, resulting in increased data volume. Increasing the number of subjects resulted in fluctuations in measurement conditions, making statistical data processing more complex. The conventional 3-D sound reproduction technology based on such measurement data therefore had problems of high computational load and individual differences in sound effects and sound quality evaluation.
MEI will incorporate this technology in its PC audio software “SD-Jukebox Ver. 4.0”, scheduled to be launched in November 2003. MEI will also consider its applications in portable audio equipment, handheld terminals and other mobile electronic devices in the future.
About Matsushita Electric Industrial Co., Ltd.
Matsushita Electric Industrial Co., Ltd. (6752), best known for its Panasonic, National, Technics, and Quasar brands, is a worldwide leader in the development and manufacture of electronics products for a wide range of consumer, business, and industrial needs. Based in Osaka, Japan, the company recorded consolidated sales of US$51.7 billion for the fiscal year ended March 31, 2002. In addition to stock exchanges in Tokyo (TSE: 6752) and elsewhere in Japan, Matsushita's shares are listed on the Amsterdam, Dusseldorf, Frankfurt, New York (NYSE: MC), Pacific, and Paris stock exchanges.For further information, please visit the Matsushita Electric Industrial Co., Ltd. home page at: www.panasonic.co.jp/global/top.html