Optimization of electrodynamic loudspeaker-design parameters by using a numerical calculation scheme

M. Rausch, R. Lerch, M. Kaltenbacher, H. Landes
Department of Electrical Measurement Technology, University of Linz, Altenbergerstr.69, A-4040 Linz, Austria

G. Krump, L. Kreitmeier
Harman Audio Electronic Systems GmbH, Schlesischestr. 135, D-94315 Straubing, Germany

Electrodynamic loudspeaker-design parameters are studied by using a recently developed modeling scheme for the numerical simulation of magnetomechanical transducers. This simulation scheme is based on a Finite-Element-Method (FEM) and allows the precise and efficient calculation of the magnetic, mechanical and acoustic fields including their couplings. Therewith, the complex dynamic behavior of moving coil drivers can be studied and, furthermore, an appropriate computer-aided-design including an optimization of critical parameters can be established.
In the present paper the validity of the simulation models is, first, verified by comparing computed and measured results. The calculated results show good agreement with the measured data. Furtheron, two practical applications, the elimination of response dips at intermediate frequencies and the improvement in efficiency for higher frequencies, are presented.

 

• 1. Introduction
• 2. Governing equations
• 2.1 Acoustic field in a fluid
• 2.2 Mechanical field in a solid
• 2.3 Magnetic field
• 2.4 Coupling 'Magnetic Field - Mechanical Field'
• 2.5 Fluid-Solid interaction
• 3. Finite element model of an electrodynamic loudspeaker
• 4. Verification of the computer model
• 5. Studies in electrodynamic loudspeaker-design parameters
• 5.1 Elimination of response dips at intermediate frequencies
• 5.2 Improvement in efficiency for higher frequencies
• 6. Conclusion