Nonlinear Electroacoustic Parameters Estimate of Moving-Coil Loudspeaker by Inverse Method

• Main Author: 王智弘
• Other Authors: 王啟昌
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/92061021827507825091

碩士 === 逢甲大學 === 電聲碩士學位學程 === 102 === This paper develops a method for estimating the important and hardly measured nonlinear electroacoustic parameters in moving-coil loudspeaker based on conjugate gradient method and variable-metric method. By measuring the information of loudspeaker displacement and current, three hardly measured mechanical domain parameters, including loudspeaker diaphragm mass , nonlinear damping coefficient and diaphragm suspension system stiffness coefficient and the two electrical domain parameters, unknown force factor and voice coil inductance and diaphragm suspension system stiffness coefficient can be calculated inversely through direct problem, adjoint equation problem and sensitivity problem calculation procedures. According to the validation of numerical simulation, the addition of coefficient scale adjustment actually improves the stability of prediction result effectively. In addition, based on simple electroacoustic measurement and numerical calculation, even if there is measurement error, this method can obtain good result, meaning the inverse electroacoustic theory proposed in this paper can reduce the effect of measurement error effectively.