CRY602 Mouth Simulator is used to simulate the sound source of the sound field near the mouth of a person, and is suitable for the acoustic parameters testing of telephone transmitters and microphones used in voice communication. The frequency response (FR) curve and other properties comply with the requirements of IEEE 269, 661 and the requirement for "mouth reference point" for transmitting acoustic signals in ITU-T P51. It is a standard sound source for acoustic measurement.