I. Overview
The M 663+A 832 is a measurement kit consisting of a 1/2-inch pre-polarized microphone capsule and a preamplifier. Its design conforms to the IEC 61094-4 WS2F international standard and is classified as a free-field microphone.
The industry term “standard microphone” or “reference microphone” refers to a precision condenser microphone that conforms to the IEC 61094 series of international standards, possesses extremely high stability and extremely low aging drift, and whose physical dimensions and acoustic characteristics are strictly regulated. Free-field microphones, on the other hand, are designed to correct for the diffraction and reflection effects on high-frequency sound waves caused by the microphone being placed in a sound field, ensuring that the measured values are the “true sound pressure level at that point before the microphone was placed.”
Due to its high stability, excellent cost performance, and extremely short lead time, the M 663+A 832 has become the standard configuration for audio production lines of many consumer electronics products.
II. Core Functions and Technological Advantages of the Product
1. Supports TEDS intelligent recognition (Transducer Electronic Data Sheet)
- Features: Built-in TEDS chip, compliant with IEEE 1451.4 standard.
- Engineering advantages: When using an audio analyzer that supports TEDS for microphone array testing, the system can directly read the microphone’s model number, serial number, and sensitivity calibration value, eliminating the need for manual input. This not only significantly reduces setup time but also eliminates the risk of human error.
2. Excellent acoustic properties
- Wideband response: Within an error range of ±2dB, the frequency response covers 3.15 Hz to 20 kHz ; within a high-precision range of ±1dB, it covers 12.5 Hz to 10 kHz, fully covering the frequency bands of human hearing and conventional audio testing.
- High sensitivity and low noise floor: Sensitivity is 50 mV/Pa (-26.0 dBV/Pa), and the noise floor is less than 18 dBA . This means it can capture subtle details while having sufficient output level to improve the signal-to-noise ratio.
- Wide dynamic range: The dynamic range covers 18 dB to 134 dB , and the maximum sound pressure level can withstand 134 dBSPL (THD < 3%), which is sufficient to cope with a variety of scenarios from quiet room noise floor to high-power speaker testing.
3. Prepolarization and IEPE power supply design
- Easy connection: It adopts a pre-polarized (Electret) design, eliminating the need for an external 200V polarization voltage.
- Universal interface: It connects via BNC interface and is powered directly by the IEPE (CCP) constant current source provided by the analyzer (typically 2-20mA), which makes cabling and system integration very simple.
III. Usage Scenarios
The M 663+A 832 is designed with a focus on “high stability” and “production line compatibility,” with typical applications including:
1. Audio product testing for mobile phones and multimedia products
- This is its core application area. Paired with the MegaSig PM 6181 audio analyzer and AM 581 artificial mouthpiece, it forms a classic “golden test combination” used to verify the factory quality of mobile phone microphones and speakers.
2. Microphone Array Testing
- Leveraging its TEDS functionality and excellent phase/frequency response characteristics, it is ideal for multi-microphone array calibration and testing in smart speakers and in-vehicle voice systems, enabling rapid channel identification and gain compensation for multi-channel systems.
3. Research and development and quality control of electroacoustic components
- As a reference microphone conforming to the IEC 61094-4 WS2F standard, it can be used in the laboratory to perform frequency response and total harmonic distortion (THD) analysis on speaker units.
IV. Specifications
| Sound field type | Free field |
| Polarization voltage | 0V (pre-polarization) |
| Frequency response | 3.15Hz – 20kHz ± 2dB 12.5Hz – 10kHz ± 1dB |
| Dynamic range | 18dB(A) – 134dB (1000 Hz distortion <3%) |
| Background noise | 18dB(A) |
| Sensitivity (mV/Pa, dBV/Pa) | 50mV (-26.0dB) ± 2dB |
| Maximum output voltage | 5.6V |
| Output impedance | <50Ω |
| Power supply | 2mA – 20mA (typical 4mA) |
| Equalization method | Post-equalization pressure |
| Interface type | BNC |
| Operating temperature range | -20℃ to 60℃ |
| Storage conditions | Temperature: 25℃±5℃, Humidity: 50%±15%RH (to ensure long-term stability of the sensor) |
| Relative humidity | 10-90% non-condensing |
| TEDS features | support |
V. Conclusion
The M 663+A 832 is an excellent product that balances “laboratory-grade precision” with “production-line-grade durability”.
For engineers, its greatest value lies in the convenience of TEDS technology and its high sensitivity of 50mV/Pa , which solves the cumbersome setup problems in multi-channel testing. If you are planning an efficient audio test line or need a reliable free-field microphone for product verification, this microphone set is a highly competitive choice.
If you require further planning consultation for your project, please feel free to contact us for technical exchange.