聲學是聲音的科學,研究它的產生、傳播、接收和效應。聲音原始是指人耳能察覺到的空氣中傳播的振動振動現象,頻率在20Hz到20KHz之間。現代已經使其范圍擴大,頻率可在20Hz以下的次聲或20KHz的超聲。Acoustics is science of sound, studying sound producing, emitting, receiving and effect. Idea of original sound mean that ear can hear a vibration of the air, frequency range is between 20Hz to 20KHz