Investigation of acoustic properties of rubber diaphragm

Ziyu Wang

doi:10.59400/sv2707

Investigation of acoustic properties of rubber diaphragm

Ziyu Wang Applied Mechanics Lab, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China

Article ID: 2707

DOI: https://doi.org/10.59400/sv2707

Keywords: moving-coil microspeakers; AEM diaphragms; large amplitude; high damping; tuning of acoustic performances

Abstract

Large amplitude and high damping play a crucial role in improving sound quality and low-frequency performance of loudspeakers, making it widely applied in electronic devices such as cellphones, tablets, and laptops. However, traditional moving-coil loudspeakers have poor damping performances, and the diaphragm of which is prone to fracture when a large excursion is applied. In this study, a novel ethyl acrylate rubber (AEM) diaphragm was fabricated through solvent casting and thermoforming and assembled to make moving-coil microspeakers (i.e., miniature loudspeakers) with excellent frequency response, amplitude, and damping performances. Meanwhile, the acoustic properties of microspeakers with different diaphragm samples were compared, and the relationships between resonance frequency and elastic modulus in the linear elastic range, the resonance frequency, and mechanical resistance of total-driver losses were revealed and validated by the calculations of mechanical stiffness of driver suspension and mechanical Q-factor of driver. The microspeakers with diaphragm samples “AEM-90-5” fabricated in this study exhibit significant and symmetric excursions; meanwhile, the acoustic properties of microspeakers in the future studies could be optimized by compositions and elastic modulus based on these samples.

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Published

2025-03-18

How to Cite

Wang, Z. (2025). Investigation of acoustic properties of rubber diaphragm. Sound & Vibration, 59(2), 2707. https://doi.org/10.59400/sv2707

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