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Experimental study of the sound quality performance and improvement of magnetic fluid speaker

자성유체 스피커의 음질 성능 및 향상에 관한 실험적 연구

  • Received : 2014.07.25
  • Accepted : 2014.12.11
  • Published : 2014.12.31

Abstract

The aim of this study was to experimentally investigate the sound quality characteristics, such as sound deflection, sound pressure level and frequency characteristics of a magnetic type speaker in an anechoic chamber to overcome the sound quality and voice-coil temperature problems. To accomplish this, the sound quality performance of the magnetic type speaker was tested according to the magnetic fluid amount and magnetic field intensity. The sound deflection, sound pressure level, and frequency characteristics were measured using the Smarrt program. As a result, at a magnetic fluid amount of 2.4 ml, the sound deflection and the sound pressure level of the magnetic type speaker were enhanced by comparing with those of the general type speaker. The frequency characteristics and the sound pressure level of the magnetic type speaker were enhanced greatly with increasing magnetic field intensity from 8.06 mT to 9.10 mT. In addition, the sound deflection of the magnetic type speaker was 0.01% lower than that of the general type speaker.

본 연구의 목적은 자성유체 스피커의 보이스 코일 방열 및 음질 저하 문제를 극복하기 위하여 무향실내에서 자성유체 스피커의 음 왜곡률, 음압레벨 및 주파수 특성과 같은 음질 성능 특성을 고찰하는 것이다. 이를 위하여 자성유체 스피커에서 자성유체 주입량 및 영구자석 자력을 변화시켜가면서 음압 성능을 측정하였다. 그리고 스피커의 음 왜곡률, 음압레벨 및 주파수 특성은 음향시스템 측정 프로그램인 Smarrt를 이용하여 측정하였다. 결과적으로, 자성유체의 주입량은 2.4 ml로 결정되었고, 자성유체를 주입할 경우 음 왜곡률 및 음압레벨은 향상되었다. 자성유체 스피커에서 영구자석의 자력을 8.06 mT에서 9.10 mT로 증가시킬 경우 주파수 특성 및 음압레벨은 더욱 향상되었다. 또한, 자성유체 스피커의 음 왜곡률은 일반 스피커에 비하여 약 0.01% 감소하였다.

Keywords

References

  1. Moo-Yeon Lee, Hyung-Jin Kim and Woo-Young Lee, 2013, "Numerical analysis on temperature characteristics of the voice-coil for woofer speaker using ferrofluid", J. of Kor. Mag. Soc., Vol. 23, No. 5, PP. 166-172. DOI: http://dx.doi.org/10.4283/JKMS.2013.23.5.166
  2. Sei Jin Oh, Fundamentals of Loudspeaker Engineering, SeokHakDang, 2006, PP. 187-196.
  3. Hyung-Jin Kim, Dea-Wan Kim and Mpp-Yeon Lee, 2013, "Experimental study on the heat transfer characteristics of woofer speaker unit", J. of KAIS, Vol. 15, No. 5, PP. 2623-2627. DOI: http://dx.doi.org/10.5762/KAIS.2014.15.5.2623
  4. Jae-Hyeong Seo, Moo-Yeon Lee and Lee-Soo Seo, 2013, "Study of Natural Convection of Magnetic Fluid in Cubic Cavity", Trans. Korean Soc. Mech. Eng. B, Vol. 37, No. 7, PP. 637-646. https://doi.org/10.3795/KSME-B.2013.37.7.637
  5. Soo-Hyun Kim, Dong-Yeon Lee and Moo-Yeon Lee, 2010, "Analysis and suppression plan for structure and flow induced noise in a small refrigeration system", J. of KAIS, Vol. 11, No. 11, PP. 4129-4136. DOI: http://dx.doi.org/10.5762/KAIS.2010.11.11.4129
  6. David C. Parker, 2004, "Speaker enclosure design on frequency response", Central Virginia Governor's School. PP. 1-15.
  7. Jong-Oh Sun and Kwang-Joon Kim, 2012, "Isolation of vibrations due to speakers in audio-visual electronic devices without deteriorating vibration of speaker cone", J. of Mechanical Science and Technology, Vol. 26, No. 3, PP. 723-730. DOI: http://dx.doi.org/10.1007/s12206-011-1227-9