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Bass Extension of Microspeaker System on Mobile Device

Published online by Cambridge University Press:  02 August 2018

J. R. Chang  and
C. N. Wang
J. R. Chang*
Affiliation:
Department of Engineering Science and Ocean Engineering National Taiwan University Taipei, Taiwan
C. N. Wang
Affiliation:
Department of Engineering Science and Ocean Engineering National Taiwan University Taipei, Taiwan
*
* Corresponding author ([email protected])
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Abstract

This study provides a solution for the bass extension of a microspeaker system in a mobile device that involves using a resonant combination of a front chamber and a rectangular, long, pipe-shaped port. The efficient resonant coupling of the microspeaker system to the acoustic load in this structure enables a microspeaker with modest cone displacement to achieve a high sound pressure level (SPL) and bass extension below the resonance of the microspeaker in free air, and the total dimensions of the structure are minimized. A combination of electro-mechanic-acoustic and finite element methods was applied to determine the SPL and bass extension levels for mobile devices. Simulation results show acceptable agreement with experimental results. A suitable extended-range microspeaker system was applied in a 10 inch tablet. The audio frequency response could be extended from 630 to 300 Hz with the greatest loudness. As much as possible add low bound frequency extension to make the article more clear. Finally, five cases of parameter settings for the front chamber volume, rear chamber volume, rectangular pipe-shaped port, cross-sectional area, and opening area were studied. The results can be applied for optimizing a suitable extended-range microspeaker system.

Keywords

A suitable extended-range microspeaker systemMirospeakerMobile deviceBass extension
Type
Research Article
Information
Journal of Mechanics , Volume 35 , Issue 4 , August 2019 , pp. 487 - 498
Copyright
© The Society of Theoretical and Applied Mechanics 2018 

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