AbstractWe conducted subjective evaluation tests to study perceptual discrimination between musical sounds with and without very high frequency components (above 21 kHz). In order to conduct strict evaluation tests, the sound reproduction system used for these tests was designed to exclude any leakage or influence of very high frequency components in the audible frequency range.
As a result, no significant difference was found between sounds with and without very high frequency components among the sound stimuli and the subjects. From these results, however, we can still neither confirm nor deny the possibility that some subjects could discriminate between musical sounds with and without very high frequency components. Nevertheless, the results also showed that the test system is entirely reliable, and that further evaluation tests using this test system will accurately show whether the very high frequency components in sound stimuli affect human recognition of sound quality.
|The subject evaluated each sound stimulus 20 times. Figure 7 shows the rate of correct response for each sound stimulus in 20 trials. Since the prior probability of correct responses was 50%, the significance probability of this evaluation test with the 20 trials was set at 72% (shown by the dashed line in Fig. 7) at a significance level of 5%. Each sound stimulus showed no significant difference, and so the subject could not discriminate between these sound stimuli with and without very high frequency components.|
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Mr. Toshiyuki Nishiguchi
He received the B. Eng. and M. Eng. degrees from the University of Electro-Communications, Tokyo, Japan, in 1994 and 1996, respectively. He joined NHK in 1996. Since 1998, he has been with NHK Science and Technical Research Laboratories. He has been engaged in the researching on microphones and high-resolution audio. He is a member of the Acoustical Society of Japan, the Institute of Image Information and Television Engineers of Japan.
|Mr. Masakazu Iwaki
He received the B. Eng. and M. Eng. degrees from the TUKUBA University, Ibaraki, Japan, in 1988 and 1990, respectively. He joined NHK in 1990. Since 1994, he has been with NHK Science and Technical Research Laboratories. He has been engaged in the researching into microphones and loudspeakers. He is a member of the Acoustical Society of Japan, the Institute of Electronics, Information and Communication Engineers (IEICE), and AES.
|Dr. Akio Ando
He received the B.S. and M.S. degrees from Institute of Design in 1978 and 1980, respectively. He also received the Dr. Eng. degree from Toyohashi University of Technology in 2001. In 1980, he joined Japan Broadcasting Corporation (NHK). He has been with the Science and Technical Research Laboratories of Japan Broadcasting Corporation since August 1983. He was in charge of developing simultaneous subtitling systems for live broadcast TV programs using speech recognition, with which NHK started simultaneous subtitled broadcasting for daily news programs on March 2000, and sports and variety programs on December 2001 including the Winter Olympic Games from Salt Lake City 2002 and the 2002 FIFA World Cup Games. He is currently a senior research engineer of the Three Dimensional Audio-visual Systems Division at the Laboratories. His research interests include pattern recognition, signal processing and acoustics. He is a member of the Institute of the Electrical and Electronics Engineers (IEEE), the Acoustical Society of Japan (ASJ), the Information Processing Society of Japan, the Association of Natural Language Processing of Japan and the Institute of Image Information and Television Engineers of Japan (ITE).