Through the comparison of the experiment data with the theory results, the damp influence of the airflow on the vibration system is analyzed. Furthermore, based on the experiment sound source, how the parameters of the vibration system may influence the voice coil amplitude, such as coefficient of elasticity, magnetic flux density, the mass, resistance, inductance and winding strands of the voice coil, is studied using equivalent circuit method. Finally, methods to choose these parameters are presented for the purpose of speech broadcasting or generating low frequency sound waves.