Excitation Experiments of a Cone Loudspeaker and Vibration-Acoustic Analysis Using FEM

To focus on the vibration mode of a cone loudspeaker,
which acts as an electroacoustic transducer, excitation experiments
were performed using two types of loudspeaker units: one employing
an impulse hammer and the other a sweep signal. The on-axis sound
pressure frequency properties of the loudspeaker were evaluated, and
the characteristic properties of the loudspeakers were successfully
determined in both excitation experiments. Moreover, under
conditions identical to the experiment conditions, a coupled analysis of
the vibration-acoustics of the cone loudspeaker was performed using
an acoustic analysis software program that considers the impact of
damping caused by air viscosity. The result of sound pressure
frequency properties with the numerical analysis are the most closely
match that measured in the excitation experiments over a wide range
of frequency bands.

Authors:

• Y. Hu
• X. Zhao
• T. Yamaguchi
• M. Sasajima
• Y. Koike

Keywords:

• Anechoic room
• finite element method
• impulse hammer
• loudspeaker
• reverberation room
• sweep signal.

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