Sound shielding control of ear protectors with PVDF

Sound shielding control of ear protectors with PVDF was evaluated. Sound attenuation level of the PVDF ear muff without circuit control was 20 - 40 dB. When the circuit control was added, the attenuation level increased by 25 - 35 dB. The controllable frequency band of the circuit was from 3 kHz to 4.2 kHz by using a PVDF as a capacitor in the circuit.