Transactions of the Korean Society for Noise and Vibration Engineering (한국소음진동공학회논문집)

The Korean Society for Noise and Vibration Engineering (한국소음진동공학회)
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Characteristics of Sound Response in Ear Canal of Human and Reproduction of Acoustical Space

인간 이도의 소리응답특성과 음향공간의 재현

  • 안태수 (동의대학교 대학원 기계공학과) ;
  • 이두호 (동의대학교 기계공학과)
  • Received : 2011.06.20
  • Accepted : 2011.08.10
  • Published : 2011.09.20
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Abstract

The human ear canal amplifies the sound pressure level at specific frequency bands. The characteristics of the ear canal are very similar to those of curved cylindrical tube. In this study, the characteristics of sound transfer in human ear canal were measured and the acoustical space of ear canal was reproduced from the canal cavity geometry. For the measurement of sound transfer function in ear canal, a probe microphone and a reference microphone were used. The sound transfer functions were measured for 5 human subjects. To reproduce the acoustical space of the ear canal, two kinds of ear simulator were designed. The first one is a straight cylindrical tube type and the other is a real-shape ear of which geometry was taken from a micro-CT scanning of a human ear. The characteristics of the reproduced apparatus were compared with those of the human and a commercial ear simulator, RA0045 of G.R.A.S. Inc. The comparison results show that the developed apparatus well represent the ear canal characteristics in the low frequency, but have limited coincidence in level over high frequency range.

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References

  1. Shaw, E. A. G., 1974, Transformation of Sound Pressure Level from the Free Field to the Eardrum in the Horizontal Plane, Journal of the Acoustic Society of America, Vol. 56, No. 6, pp. 1848-1861. https://doi.org/10.1121/1.1903522
  2. Shaw, E. A. G., 1975, The External Ear : The New Knowledge, Scandinavian Audiology, Vol. 5, pp. 24-50.
  3. Chan, J. C. K. and Giesler, C. D., 1990, Estimation of Eardrum Acoustic Pressure and of Ear Canal Length from Remote Points in the Canal, Journal of the Acoustic Society of America, Vol. 87, No. 3, pp. 1237-1247. https://doi.org/10.1121/1.398799
  4. Jeong, H. S., Koo, H. E., Lee, S. M., Koo, S. K., Lee, S. H. and Yu, T. H., 2001, Changed in Resonance Frequency and Length of External Auditory Canal Related to the Age, Korean Journal of Otorhinolaryngology-Head and Neck, Vol. 44, No. 2, pp. 144-147.
  5. Stinson, M. R. and Lawton, B. W., 1989, Specification of the Geometry of the Human Ear Canal for the Prediction of Sound Pressure Level Distribution, Journal of the Acoustic Society of America, Vol. 85, No. 6, pp. 2492-2503. https://doi.org/10.1121/1.397744
  6. Moon, S.-K., Chung, M.-H., Kim, H.-N. and Shim, Y. J., 1993, The Characteristics of Resonance Frequency in Human External Ears According to Structural Differences, Korean Journal of Otorhinolaryngology-Head and Neck, Vol. 36, No. 6, pp. 1115-1123.
  7. Hawkins, D., Alvarez, E. and Houlihan, J., 1991, Reliability of Three Types of Probe Microphone Measurements, Hear. Instrum., Vol. 42, pp. 14-16.
  8. Ahn, T.-S. and Lee, D. H., 2010, Measurement of Sound Pressure Level in Ear Canal of Korean, Proceedings of the KSNVE 20th Anniversary Spring Conference, pp. 746-747.
  9. Ickes, M. A., Hawkins, D. B. and Cooper, W. A., 1991, Effect of Reference Microphone Location and Loudspeaker Azimuth on Probe Tube Microphone Measurements, Journal of the American Academy of Audiology, Vol. 2, No. 3, pp. 156-163.
  10. Zemplenyi, J., Gilman, S. and Dirks, D., 1985, Optical Method for Measurement of Ear Canal Length, Journal of the Acoustic Society of America, Vol. 78, No. 6, pp. 2146-2148. https://doi.org/10.1121/1.392676
  11. Hudde, H., 1983, Estimation of the Area Function of Human Ear Canals by Sound Pressure Measurements, Journal of the Acoustic Society of America, Vol. 73, No. 1, pp. 24-31. https://doi.org/10.1121/1.388857
  12. Hudde, H. and Engel, A., 1998, Measuring and Modeling Basic Properties of the Human Middle Ear and Ear Canal, Acta Acustica United with Acustica, Vol. 84, No. 4, pp. 720-738.
  13. Lee, D. H. and Ahn, T.-S., 2008, Development of Experimental Dummy and Measurements of Head-related Transfer Function(HRTF) for Averaged Korean Head Shape, Transactions of the Korean Society for Noise and Vibration Engineering, Vol. 18, No. 8, pp. 841-848. https://doi.org/10.5050/KSNVN.2008.18.8.841
  14. 3-D Doctor User's Guide, Woorimtech.
  15. Test.Lab Spectral Testing User Manual, LMS Korea.
  16. Ahn, T.-S. and Lee, D. H., 2009, Comparison of Measurement Methods for Head-related Transfer Function(HRTF), Transactions of the Korean Society for Noise and Vibration Engineering, Vol. 19, No. 12, pp. 1260-1268. https://doi.org/10.5050/KSNVN.2009.19.12.1260