Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
Kazuhiko Kawahara Last modified date:2021.07.14

Associate Professor / Sound Culture / Art Management / Department of Communication Design Science / Faculty of Design


Papers
1. Kazuhiko Kawahara, Masayuki Takada, Shin-Ichiro Iwamiya, How to listen professionally
Advanced technical listening training program at Kyushu University, 25th International Congress on Sound and Vibration 2018: Hiroshima Calling, ICSV 2018 , 8, 5113-5117, 2018.01, Recently, various technical ear-training programs have been introduced to audio and acoustic engineering communities. Technical listening training (TLT) is a systematic training program at Kyushu University designed to improve auditory sensitivity for acoustic learning students. Basic-course TLT (TLT I) focuses on basic acoustic properties: frequency, sound pressure level and spectrum. TLT II as advanced course of TLT I, consists of more practical training tasks. It further explores the identification of enhanced frequency of colored music. In addition, it includes training in identification of low-cut and high-cut frequencies. As an advanced identification training exercise in the sound pressure level difference, it includes the identification task of mixing level balance of music ensemble. This training simulates control of the mixing console for music recordings. Further tasks are identification of spectrum envelope slope of harmonic complex tones, reverberation time of noise, impulse and music excerpt, signal and noise ratio, and quantizing bit depth of recorded music. TLT II includes lectures on sound color, concept of auditory filter, consonance theory. Students also learn sound quality metrics; sharpness, roughness, and fluctuation strength. Students are expected to understand the relationship between physical properties of sounds and auditory perception. This understanding contributes to further effectiveness of TLT. Furthermore, they learn the concept of soundscape and brush up sensitivity to everyday sounds through the sound education program..
2. Moe Nishikawa, Akiho Fujimori, Kazuhiko Kawahara, Akira Omoto, Yutaka Kamamoto, Takehiro Moriya, Extraction of applause from a sound field for ambient transmission in a live viewing system, 6th IEEE Global Conference on Consumer Electronics, GCCE 2017 , 10.1109/GCCE.2017.8229366, 2017-January, 1-3, 2017.12, Live performances are increasingly appreciated using popular commercial audiovisual transmission systems, such as live viewing systems. A reality enhancement method for live viewing had been proposed. This paper describes an applause sound extraction method for automation of applause sound transmission and a simulation experiment using the sound source recorded live at the venue to assess the applause sound extraction performance. We used an adaptive filter to emphasize applause sounds and extracted them using signal amplitude information. The experimental evaluation showed that the applause sound was extracted almost correctly from the performance sound source under various conditions..
3. Kazuhiko Kawahara, Kosuke Goto, Design and performance evaluation of a stereo sound reproduction system with a complementary distributed mode loudspeaker, 4th IEEE Global Conference on Consumer Electronics, GCCE 2015 , 10.1109/GCCE.2015.7398526, 34-37, 2016.02, This paper proposes an effective method to use a Distributed Mode Loudspeaker (DML). DMLs are loudspeakers with strong diffusion properties. In this paper, we proposed a sound reproduction system with a DML. The sound field generated by the proposed reproduction system is measured by the index of diffusivity. As a result, it is concluded that the sound field generated by the proposed reproduction system has a higher diffusivity when compared with a conventional reproduction system. The proposed system also demonstrates strong results with respect to the influence of the chamber's acoustic boundary on sound quality..
4. Kazuhiko Kawahara, Masayuki Takada, Shin-ichiro Iwamiya, Transferring technical listening training curriculum at the Department of Acoustic Design, Kyushu University, to a corporation in the acoustics industry, Acoustical Science and Technology, 37, 4, 157-164, 2016.07, Technical listening training (TLT) is a systematic training program designed to improve auditory sensitivity. TLT consists of discrimination and identification tasks for a wide variety of acoustic features, e.g., frequency, sound pressure level, and spectrum pattern. To improve the auditory sensitivity of employees in a corporation in the acoustics industry, the TLT curriculum at the Department of Acoustic Design, Kyushu University (KU), was transferred to the corporation as part of a corporate education program. An initial 5-day trial course was carried out by the KU staff to demonstrate the process of KU-style TLT and its effectiveness to the corporate staff. After the creation of a TLT control system and training room, a second trial 11-day course was jointly carried out by KU and the corporate staff as a simulation of the TLT course in the corporation. Participants in the trials were engineers in the corporation. Through the TLT trials, they improved their auditory sensitivity and their understanding of the relationship between acoustic properties and auditory attributes. They recognized the importance of the systematic listening experiences provided by TLT. Through these two trials, the corporate staff gained understanding of the TLT curriculum. Therefore, the corporation has begun running the TLT curriculum smoothly and successfully..
5. Kazuhiko Kawahara, Masayuki Takada, Shin-ichiro Iwamiya, (ACOUSTICAL LETTER)Training course for instructors of Technical Listening Training, Acoustical Science and Technology, 37, 4, 185-186, 2016.07.
6. Customized System for Technical Listening Training at Department of Acoustic Design, Kyushu University.
7. Introduction of "Technical Listening Training" as the First Class of the Specialized Curriculm of Department of Acoustic Design.
8. KIM KIHONG, Kazuhiko Kawahara, Shin-ichiro Iwamiya, (Acoustical Letter)Case study of acoustic education for Korean music majors, Acoustical Science and Technology, 35, 1, 62-65, 2014.01.
9. Shin-ichiro Iwamiya,Yoshitaka Nakajima,Kazuo Ueda, Kazuhiko Kawahara and Masayuki Takada, Technical Listening Training: Improvement of sound sensitivity
for acoustic engineers and sound designers, Acoustical Science and Technology, Vol.24,No.1,pp.27-31, 2003.01.
10. Study on Repiratory Control Methods for Measurement on Heart Rate Variability.