Underwater acoustic characterization of electret hydrophone with speaker as sound source

In this paper, we fabricated a hydrophone using electret microphone and an underwater speaker and characterized acoustically in air and in water. Fabricated electret hydrophone is connected to a pre-amplifier and audio amplifier and speaker transmits amplified sine wave from a signal generator. Preliminary characterization results were presented. Frequency response and SNR vs. Frequency plots show that hydrophone’s responsive bandwidth is from 500 Hz to 100 kHz, in water and 480 Hz to 100 kHz in air.