Daying road, meilan district. According to Baidu map, Haikou second-hand audio equipment market refers to second-hand audio shops, located in Daying Road, Meilan District, Haikou City, Hainan Province. Audio refers to a set of audio system which is composed of electrical equipment to produce sound. Refers to the power amplifier in the speaker main box or subwoofer box, which amplifies the audio signal and then plays back the sound by the audio itself.