A sound also has an amplitude, a property subjectively heard as loudness.The amplitude of a sound is the measure of the displacement of the air pressure wave from its mean, or quiescent state.是什么意思_A sound also has an amplitude, a property subjectively heard as loudness.The amplitude of a sound is the measure of the displacement of the air pressure wave from its mean, or quiescent state.在线翻译_英语_读音_用法_例句