Midwoofer Harmonic Distortion Analysis with KLIPPEL Measurements
Application ID: 121161
An automotive midwoofer is modeled using the lumped parameter approach. The electrical and mechanical components are modeled using a lumped electric circuit, which is coupled to a finite element model for the acoustics using the Lumped Speaker Boundary feature. The large signal parameters CMS(x), BL(x), LE(x), L2(x), and R2(x) are considered as nonlinear functions of excursion, while the remaining lumped parameters are constants. The output from the model includes the excursion and the sound pressure levels for excitation voltages ranging from 2 to 10 V, for frequencies up to 500 Hz.
The cone geometry was measured by KLIPPEL laser scan and converted to .dxf file for use in the finite element model. The lumped parameters, excursion, and sound pressure levels were measured by KLIPPEL [Data created by KLIPPEL using the KLIPPEL Analyzer System].
Results from the model are validated against measurements including (1) the harmonic distortion (first three harmonics for sound pressure level at a reference distance of 1 m on-axis), and (2) the excursion (change in the fundamental with increasing voltage).
KLIPPEL is an innovative leader in providing unique test equipment for electro-acoustical transducers and audio systems. See www.klippel.de.
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