Convention Paper
Analysis and Optimal Design of Miniature Loudspeakers
AES Convention 120 · Paper 6840 · May 2006
Abstract
Miniature loudspeakers are key components to many 3C products especially for portable devices such as mobile phones, PDAs, MP3, etc. Due to size limitation, miniature loudspeakers suffer from the problem of low output level. To gain higher output, one tends to drive the miniature loudspeaker over the excursion limit and induce another problem – nonlinear distortion. This paper presents a systematic analysis and design procedure appropriate for miniature loudspeakers to best reconcile the tradeoff between total harmonic distortion (THD) and sound pressure level (SPL). The paper begins with the identification of the electro-acoustic parameters of loudspeaker via the test-box method. Performance indices including voice-coil impedance, frequency response and harmonic distortion are evaluated. On the basis of the preceding model, optimization procedures are carried out to pinpoint an optimal design. The results reveal that both output performance and excursion limit of the miniature loudspeaker can be improved by using the optimal design.
