Application Scenario and Specifications of M902 Simulated Mouth

• Application Scenario: Sound source for acoustic measurement of microphones (including transducers) and similar devices.

• Compliant Standard: ITU-T Rec. P.51

• Frequency Range: Minimum sound pressure level (SPL) of 110 dB re. 20 μPa, covering 100 Hz – 10 kHz.

• Distortion:

• < 1.5% (at 200 Hz – 300 Hz, 94 dB SPL at the Measurement Reference Point/MRP);

• < 1% (at 300 Hz – 10 kHz, 94 dB SPL at the MRP).

• Maximum Power: 15 W

• Operation Mode: Passive

The M902 Simulated Mouth is designed by Shenzhen Hongzhe Technology Co., Ltd. It is a sound source engineered to simulate the acoustic field environment of a human mouth, complying with international standards IEEE 269 and ITU-T Rec. P.51. Typically, it is used to test the frequency response of telephone microphones and communication microphones. Featuring extremely high stability and low distortion, the M902 is an ideal sound source for acoustic microphone testing.

The Measurement Reference Point (MRP) of the simulated mouth is located 35 mm away from the mouth (with the lower lip ring removed). There are two methods for calibrating the mouth: aligning at 0° or 90° relative to the central axis of the simulated mouth. Using these two calibration methods, adjust the standard microphone and fix it accurately at the MRP to perform calibration of the simulated mouth. Within the frequency range of 100 Hz to 10 kHz, the simulated mouth can generate a minimum continuous equalized signal of 100 dB (referenced to 20 μPa). Its loudspeaker receives external analog signals directly via a BNC connector.