Optimization of Loudspeaker Part Design Parameters by Air Viscosity Damping Effect

Authors: Yue Hu, Xilu Zhao, Takao Yamaguchi, Manabu Sasajima, Yoshio Koike, Akira Hara

Abstract:

This study optimized the design parameters of a cone loudspeaker as an example of high flexibility of the product design. We developed an acoustic analysis software program that considers the impact of damping caused by air viscosity. In sound reproduction, it is difficult to optimize each parameter of the loudspeaker design. To overcome the limitation of the design problem in practice, this study presents an acoustic analysis algorithm to optimize the design parameters of the loudspeaker. The material character of cone paper and the loudspeaker edge were the design parameters, and the vibration displacement of the cone paper was the objective function. The results of the analysis showed that the design had high accuracy as compared to the predicted value. These results suggested that although the parameter design is difficult, with experience and intuition, the design can be performed easily using the optimized design found with the acoustic analysis software.

Keywords: Air viscosity, design parameters, loudspeaker, optimization.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1127565

References:

[1] W. N. Brown Jr, “Theory of conical sound radiators,” J. Acoust. Soc. Am., Vol. 13, no. 1, pp. 20–22, 1941.7.
[2] P. G. Bordoni, “The conical sound source,” J. Acoust. Soc. Am., vol. 28, no. 2, pp. 123–126, 1945.
[3] T. Nimura, E. Matsui, K. Shibayama, K. Kido, “Study on the cone type dynamic loudspeakers,” J. Acoust. Soc. Jpn., vol. 7, no. 2, pp. 16–28, 1952.
[4] F. J. Frankfort, “Vibration and sound radiation of loudspeaker cones,” Thesis, Delft(1975); also Philips Res. Rep. Suppl., no. 2, 1975
[5] T. Ueno, K. Takahashi, K. Ichida, S. Ishii, “The vibration analysis of a cone loudspeaker by the finite element method,” J. Acoust. Soc. Jpn., vol. 34, no. 8, pp. 470–477, 1978.
[6] I. Suzuki, K.Nomoto, “Computerized analysis and observation of the vibration modes of a loudspeaker cone,” Journal audio Eng. Soc., no.1280, pp.1-9, 1982.
[7] N. Kyouno，T. Usagawa, T. Yamabuchi, Y. Kagawa, “Acoustic response analysis of a cone-type loudspeaker by the finite element method,” J. Acoust. Soc. Jpn., vol. 61, no. 6, pp. 312–319, 2005.
[8] Y. Nomura, K. Nagasawa, “Design of the phase inverter loudspeaker system by nonlinear optimization method,” J. Acoust. Soc. Jpn., vol. 34, no. 8, pp. 462–469, 1978.
[9] F. Kusudo, “Design of loudspeaker by optimization method,” Reports of the spring meeting the Acoustical Society of Japan, pp. 263–264, 1979
[10] M. Sasajimai T. Yamaguchi, M. Watanabe, Y. Koike, “FEM analysis of a narrow acoustic sound pathway with rectangular cross section,” Society of Damping Technology, vol. 12, 2014.
[11] X. Zhao, “Some new problems and measure with structural optimization software development,” Proceedings of the Conference on Computational Engineering and Science, vol. 12, no. 1, 129–132, 2007
[12] X. Zhao, Y. Hu, I. Hagiwara, “Optimal design for crash characteristics of cylindrical thin-walled structure using origami engineering,” The Japan Society of Mechanical Engineers, vol. 76, no. 761, 2010