著者
Taguti Tomoyasu Ohtsuki Katsuya Yamasaki Teruo Kuwano Sonoko Namba Seiichiro
出版者
ACOUSTICAL SOCIETY OF JAPAN
雑誌
Acoustical Science and Technology (ISSN:13463969)
巻号頁・発行日
vol.23, no.5, pp.244-251, 2002 (Released:2002-09-01)
参考文献数
17
被引用文献数
2

Tone stopping is the act of ending the vibration of a piano string by the contact of the damper. This paper studies the perceptual effect of tone stopping. Five performances of a music passage were synthesized with piano tones of simulated tone stopping at sound level, i.e., with the tones that were obtained by processing the waveform of a single, sustained tone of a real piano to induce a desired ending profile with the onset portion kept intact. These performances were rated by ten musically trained subjects with the method of paired comparisons on twenty adjectives. The result indicated that: (1) a short plateau followed by a slow decay made the tone reverberating, lustrous, and beautiful, (2) a long plateau followed by a fast decay made the tone sticky, immature, and blunt, and (3) a short plateau followed by a fast decay made the tone tight, sharp, and nimble.
著者
Akinori Ito
出版者
ACOUSTICAL SOCIETY OF JAPAN
雑誌
Acoustical Science and Technology (ISSN:13463969)
巻号頁・発行日
vol.41, no.1, pp.166-169, 2020-01-01 (Released:2020-01-06)
参考文献数
40

This article briefly reviews the research works related to metacommunication. Metacommunication is a term meaning ``communication on communication,'' which is related to marginal communication such as conveying recognition, comprehension, and evaluation of an interlocutor's words. Herein, several research works are reviewed from the metacommunication point of view.
著者
Makoto Morinaga Junichi Mori Takanori Matsui Yasuaki Kawase Kazuyuki Hanaka
出版者
ACOUSTICAL SOCIETY OF JAPAN
雑誌
Acoustical Science and Technology (ISSN:13463969)
巻号頁・発行日
vol.40, no.6, pp.391-398, 2019-11-01 (Released:2019-11-01)
参考文献数
15
被引用文献数
6

We have been developing an aircraft model identification system that uses a convolutional neural network (CNN). The assumption is that this identification system would be used to estimate the number of flights to create noise maps. In our previous study, we used the CNN model to classify five aircraft comprising three rotorcraft, one turboprop, and one jet aircraft, and the accuracy reached 99%. In the present study, to examine whether this method is also effective for identifying the sound sources of jet aircraft, we conducted two case studies using frequency characteristics of aircraft noise obtained from field measurements around Osaka International Airport and Narita International Airport. Targeting 7 and 18 types of sound source at Osaka and Narita, respectively, an identification rate of 98% was obtained in both cases. This suggests that the present system can estimate the number of jet aircraft flights for each engine type or each aircraft model with very high accuracy.
著者
Cohen David Rossing Thomas D.
出版者
ACOUSTICAL SOCIETY OF JAPAN
雑誌
Acoustical Science and Technology (ISSN:13463969)
巻号頁・発行日
vol.24, no.1, pp.1-6, 2003 (Released:2003-01-01)
参考文献数
14
被引用文献数
4

Using electronic TV holography, we have studied the vibrational modes of four mandolins and a mandola. The lowest (0,0) modes may appear either as a triplet (as in a guitar) or as a doublet. The modal frequencies correlate well with the frequency response curves. Sound spectra indicate that sound radiation is quite uniform over the 0–5 kHz range with some rolloff above 2.5 kHz.
著者
Tsubasa Kusano Kohei Yatabe Yasuhiro Oikawa
出版者
ACOUSTICAL SOCIETY OF JAPAN
雑誌
Acoustical Science and Technology (ISSN:13463969)
巻号頁・発行日
vol.39, no.3, pp.215-225, 2018-05-01 (Released:2018-05-01)
参考文献数
47
被引用文献数
2

In marine seismic surveys to explore seafloor resources, the structure below the seafloor is estimated from the obtained sound waves, which are emitted by a marine seismic sound source and reflected or refracted between the layers below the seafloor. In order to estimate the structure below the seafloor from returned waves, information of the sound source position and the sound speed are needed. Marine seismic vibrators, which are one of the marine seismic sound sources, have some advantages such as high controllability of the frequency and phase of the sound, and oscillation at a high depth. However, when the sound source position is far from the sea surface, it becomes difficult to specify the exact position. In this paper, we propose a method to estimate the position of a marine seismic vibrator and the sound speed from obtained seismic data by formulating an optimization problem via hyperbolic Radon transform. Numerical simulations confirmed that the proposed method almost achieves theoretical lower bounds for the variances of the estimations.
著者
Patricia K. Kuhl
出版者
一般社団法人 日本音響学会
雑誌
Acoustical Science and Technology (ISSN:13463969)
巻号頁・発行日
vol.28, no.2, pp.71-83, 2007 (Released:2007-03-15)
参考文献数
79
被引用文献数
5 13
著者
Nishiguchi Masayuki
出版者
一般社団法人日本音響学会
雑誌
Acoustical science and technology (ISSN:13463969)
巻号頁・発行日
vol.27, no.6, pp.375-383, 2006-11

A coding algorithm for speech called harmonic vector excitation coding (HVXC) has been developed that encodes speech at very low bit rates (2.0-4.0kbit/s). It breaks speech signals down into two types of segments: voiced segments, for which a parametric representation of harmonic spectral magnitudes of LPC residual signals is used; and unvoiced segments, for which the CELP coding algorithm is used. This combination provides near toll-quality speech at 4.0kbit/s, and communication-quality speech at 2.0kbit/s, thus outperforming FS1016 4.8-kbit/s CELP. This paper discusses the encoder and decoder algorithms for HVXC, including fast harmonic synthesis, time scale modification, and pitch-change decoding. Due to its high coding efficiency and new functionality, HVXC has been adopted as the ISO/IEC International Standard for MPEG-4 audio.
著者
Yôiti Suzuki Hisashi Takeshima Kenji Kurakata
出版者
ACOUSTICAL SOCIETY OF JAPAN
雑誌
Acoustical Science and Technology (ISSN:13463969)
巻号頁・発行日
pp.e23.66, (Released:2023-10-25)
参考文献数
14

As significant errors were reported in 1985 for the international standard related to equal-loudness-level contours (ELLCs) for pure tones, the earlier international standard was fully revised in 2003 as ISO 226:2003, after 18 years of revision work. Twenty years later, the standard has been revised again as ISO 226:2023. One motivation for the revision was to reflect the lowering of the threshold of hearing at 20 Hz by 0.4 dB in ISO 389-7:2019. In addition, the following two points of substance were revised: (1) implementation of the power exponent relating loudness perception to physical intensity formulated in an academic paper published in 2004, which describes the derivation of ELLCs relating to ISO 226:2003, and (2) adoption of mathematical expressions that preserve the appropriate number of significant digits. In this review, the process of the revision and the technical details of the changes are described. The differences from the 2003 edition are only 0.6 dB at most, and the 2023 standard can be regarded as the same as the 2003 edition in terms of practical use.
著者
Jürgen Herre Schuyler R. Quackenbush
出版者
ACOUSTICAL SOCIETY OF JAPAN
雑誌
Acoustical Science and Technology (ISSN:13463969)
巻号頁・発行日
vol.43, no.2, pp.143-148, 2022-03-01 (Released:2022-03-01)
参考文献数
14
被引用文献数
1

The term "Immersive Audio" is frequently used to describe an audio experience that provides to the listener the sensation of being fully immersed or "present" in a sound scene. This can be achieved via different presentation modes, such as surround sound (several loudspeakers horizontally arranged around the listener), 3D audio (with loudspeakers at, above and below listener ear level) and binaural audio to headphones. This article provides an overview of the recent MPEG standard, MPEG-H 3D Audio, which is a versatile standard that supports multiple immersive sound signal formats (channels, objects, higher order ambisonics), and is now being adopted in broadcast and streaming applications.
著者
Sungyoung Kim
出版者
ACOUSTICAL SOCIETY OF JAPAN
雑誌
Acoustical Science and Technology (ISSN:13463969)
巻号頁・発行日
vol.41, no.1, pp.129-133, 2020-01-01 (Released:2020-01-06)
参考文献数
20
被引用文献数
1

This paper reviews previous experimental studies on the relationship between a listener's cultural framework and auditory perception of an enclosed space. Cultural influence on auditory perception of noise and music has been assessed through a range of studies. Is it same for spatial hearing? When we enter to a space, would a particular cultural framework influence on understanding of the corresponding auditory environment? As physical buildings and enclosures reflect architectural and visual heritage, the auditory environment of an enclosed space also represents a unique and distinct heritage where people have interacted with and shaped their culture. When two listener groups (East-Asian and North-American) compared a reproduced field, previous findings show that (1) the semantic value of a same descriptor was distinctly different for two groups, and (2) there was an inverse relationship between the area of a personal space and size of a desired (preferred) auditory environment. With the advance of virtual reality (VR) technology, listeners can enter any auditory environment ubiquitously. Therefore, researchers and developers in the field should consider multiple user groups and the role of cultural framework in virtual environments.
著者
Takao Tsuchiya Yusuke Makino Yu Teshima Shizuko Hiryu
出版者
ACOUSTICAL SOCIETY OF JAPAN
雑誌
Acoustical Science and Technology (ISSN:13463969)
巻号頁・発行日
vol.44, no.2, pp.101-109, 2023-03-01 (Released:2023-03-01)
参考文献数
28
被引用文献数
2

This paper reports on the implementation of a moving sound source and receiver with directivity in the two-dimensional finite-difference time-domain (FDTD) method. A two-dimensional fundamental solution of a moving monopole source is theoretically derived. Then, a fundamental solution of a moving dipole source is obtained by differentiating the fundamental solution of a monopole source in space. Finally, the directivity of moving monopole, dipole, and cardioid sources is theoretically derived. Numerical experiments performed on the two-dimensional sound field showed that the effect of moving velocity on amplitude differs for the monopole and dipole sources. Furthermore, it was found that directivity characteristics of dipole and cardioid sources vary depending on the beam steering angle and moving direction. The present method can be accurately applied to the moving sound source and receiver with directivity.
著者
Valbona Berisha Shukri Klinaku
出版者
ACOUSTICAL SOCIETY OF JAPAN
雑誌
Acoustical Science and Technology (ISSN:13463969)
巻号頁・発行日
vol.44, no.1, pp.24-28, 2023-01-01 (Released:2023-01-01)
参考文献数
17
被引用文献数
2

The principle of relativity requires that laws be invariant in all inertial reference frames. The laws of mechanics are invariant to Galilean relativity. The acoustic wave equation is a mechanical law. So why does the acoustic wave equation turn out to be noninvariant to Galilean transformation? What does this mean? Why do the principle of relativity, the wave equation, and the current Galilean transformation not agree between them? Indeed, to provide the invariance of the wave equation, the Galilean transformation must be transformed. The transformed Galilean transformation has a wide base of arguments.
著者
Shigeaki Amano Hideki Kawahara Hideki Banno Katuhiro Maki Kimiko Yamakawa
出版者
ACOUSTICAL SOCIETY OF JAPAN
雑誌
Acoustical Science and Technology (ISSN:13463969)
巻号頁・発行日
vol.43, no.2, pp.105-112, 2022-03-01 (Released:2022-03-01)
参考文献数
30

A perception experiment and analyses were conducted to clarify the acoustic features of pop-out voice. Speech items pronounced by 779 native Japanese speakers were prepared for stimuli by mixing them with a babble noise that consisted of overlapping short sentences spoken by 10 Japanese speakers. Using a 5-point scale, 12 Japanese participants rated the pop-out score of the speech items listened using headphones. The scores and acoustic features of the speech items were investigated using correlation analysis and principal coordinate analysis. It was revealed that the pop-out score relates to the acoustic features such as overall intensity, relative intensity in the high-frequency range, fundamental frequency, dynamic feature of the spectrum, and a spectrum shape in high frequency. The results suggest that these are crucial acoustic features for the pop-out voice.
著者
Kimiko Yamakawa Shigeaki Amano Mariko Kondo
出版者
ACOUSTICAL SOCIETY OF JAPAN
雑誌
Acoustical Science and Technology (ISSN:13463969)
巻号頁・発行日
vol.43, no.5, pp.241-250, 2022-09-01 (Released:2022-09-01)
参考文献数
27

Vietnamese speakers' mispronunciations of Japanese singleton and geminate stops were identified using the category boundary of the stops pronounced by native Japanese speakers. To clarify the characteristics of the Vietnamese speakers' mispronunciations, their speech segment durations were analyzed. In comparison with native Japanese speakers' correct pronunciations, Vietnamese speakers mispronounced a singleton stop with a longer closure and a shorter preceding consonant-vowel segment, whereas they mispronounced a geminate stop with a shorter closure and a longer following consonant-vowel segment. These results were consistent with the findings of Korean, Taiwanese Mandarin, and Thai speakers in previous studies, suggesting that non-native speakers may have a common tendency to have inadequate durations of closure and anteroposterior consonant-vowel segments in mispronunciations of Japanese singleton and geminate stops.
著者
Seiji Adachi
出版者
ACOUSTICAL SOCIETY OF JAPAN
雑誌
Acoustical Science and Technology (ISSN:13463969)
巻号頁・発行日
vol.25, no.6, pp.400-405, 2004 (Released:2004-11-01)
参考文献数
41
被引用文献数
4 5

This paper presents an outline of the sound production mechanisms in wind instruments and reviews recent progress in the research on different types of wind instruments, i.e., reed woodwinds, brass, and air-jet driven instruments. Until recently, sound production has been explained by models composed of lumped elements, each of which is often assumed to have only a few degrees of freedom. Although these models have achieved great success in understanding the fundamental properties of the instruments, recent experiments using elaborate methods of measurement, such as visualization, have revealed phenomena that cannot be explained by such models. To advance our understanding, more minute models with a large degree of freedom should be constructed as necessary. The following three different phenomena may be involved in sound production: mechanical oscillation of the reed, fluid dynamics of the airflow, and acoustic resonance of the instrument. Among them, our understanding of fluid dynamics is the most primitive, although it plays a crucial role in linking the sound generator with the acoustic resonator of the instrument. Recent research has also implied that a rigorous treatment of fluid dynamics is necessary for a thorough understanding of the principles of sound production in wind instruments.