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Optimization of orthotropic distributed-mode loudspeaker using attached masses and multi-exciters
Guochao Lu1, Yong Shen, Ziyun Liu
1Key Laboratory of Modern Acoustics (Ministry of Education), Nanjing University, 22 Hankou Road, Gulou District, Nanjing 210193, People's Republic of China. lgcatnju@gmail.com
The Journal of the Acoustical Society of America
|February 23, 2012
Summary
This study optimizes distributed-mode loudspeaker (DML) sound response. Methods include attached masses to modify plate modes and multi-exciters for response smoothing, improving DML performance.
Area of Science:
- Acoustics
- Mechanical Engineering
- Materials Science
Background:
- Distributed-mode loudspeakers (DMLs) offer unique sound radiation properties.
- Optimizing the frequency response of DMLs is crucial for high-fidelity audio reproduction.
- Existing methods for DML response control have limitations.
Purpose of the Study:
- To investigate a novel method for optimizing the sound response of distributed-mode loudspeakers (DMLs).
- To enhance the modal distribution and smooth the frequency response of DMLs.
Main Methods:
- Utilized an orthotropic plate model for analysis.
- Implemented an attached masses technique to alter the plate's modal distribution.
- Employed a multi-exciter approach to smooth the resulting sound response.
Main Results:
- The attached masses method effectively rebuilt the plate's modes distribution.
- The multi-exciter method successfully smoothed the sound response based on the modified modes.
- The combined approach demonstrated significant optimization of the DML's sound output.
Conclusions:
- The investigated method provides an effective means to optimize DML sound response.
- This technique offers a viable solution for achieving smoother and more predictable DML performance.
- Further research can explore variations in mass placement and exciter configurations.
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