Loudspeaker analysis -- Voice Coil Motion

In this gallery page, we have analyzed the voice coil response to a signal by using the 2D Transient with motion solver. The solver includes coupling to the mechanical equations of motion, so that the movement of a component of a device (for example, the movement of the voice coil) is accurately simulated. The mechanical effects can include friction, inertia, mass, springs, gravitation, etc.

NOTE The initial transients are evident for the first 2 cycles in all of the graphs listed below. Also, the nonlinearity in the response of the voice coil due to the nonlinearity in the gap field is very evident.

Results

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Using the model shown above as a starting point, we define how the voice coil is suspended by defining a spring with a coefficient corresponding to the compliance of the speaker cone. In the illustration to the right, we show the spring coefficients used in the analysis.

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This graph shows the Force for a sinusoidal current input, as a function of time.

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This graph shows the Position of the voice coil, as a function of time.

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This graph shows the Speed of the voice coil, as a function of time.

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This graph shows the Voice coil acceleration, as a function of time.