How to Calculate Damping Factor

The performance of a car speaker depends on the damping factor and resistance of the speaker.

The damping factor is the ability of the speaker to resist movement when an electric voltage is applied to the speaker. The higher the damping factor, the shorter the tone is generated by the speaker. Damping factors that are too low create distortion with quickly changing tones and echos when the sound is stopped. The damping factor is calculated based upon the difference in voltage passing through the speaker when a load is applied versus no load.

Things You'll Need

• Voltmeter
• Speaker

Instructions

1. Place the contacts of the voltmeter across the input and output contacts of the speaker.

2. Measure the voltage with no sound being played through the speaker to the get the no-load voltage.

3. Put a noise (typically at 50 hertz) through the speaker to the get the load voltage.

4. Divide the no-load voltage by the no-load voltage minus the load voltage to get the damping factor.

References

• Basic Car Audio Electronics: Damping Factor