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This new version is a factory-assembled combination of a 1/2" pre-polarized pressure-field microphone cartridge (Type 4971) and a high temperature 1/2" Constant Currant Line Drive (CCLD) preamplifier (Type 1706 with BNC connector), which connects to CCLD input conditioning, thus ensuring all measurements can be conducted using a general data acquisition system. The microphone cartridge and preamplifier are sealed together and are considered as one unit with a single type and serial number stored in the TEDS chip.
Type 4971-H-041 is optimized for use in pressure-field applications, such as with couplers measuring close to audio device sound ports or flush-mounting. It’s also suitable for random incidence measurements and free-field measurements with 90°C incidence. This makes it ideal for measuring moving objects like trains or planes, as - even though the object is moving - the frequency characteristic stays the same.
The microphone’s wide frequency range (5 Hz to 20 kHz, ±2 dB), broad dynamic range (20 dB(A) to 146 dB) and immunity to harsh, unpredictable environments also makes it suitable for component testing within telecom, audio, automotive and aerospace industries. Its immunity to changing environmental conditions make it the go-to microphone for pressure-field measurements.
The microphone is supplied with Brüel&Kjær Microphone Viewer, an application which users can install on a PC. The application contains frequency correction curves for different conditions and other useful information, such as the influence of different accessories on the frequency response. The correction data can be uploaded to PULSE LabShop or BK Connect, where it can be used to correct the frequency response in real time according the actual conditions during use, or exported as a Microsoft Excel file for use in applications such as MATLAB. This data is also available online.
Brüel & Kjær focuses on sound and vibration solutions and develops advanced technology for measuring and managing sound and vibration. HBK – Hottinger, Brüel & Kjær, home to the HBM Test and Measurement and Brüel & Kjær Sound and Vibration brands, is a subsidiary of UK-based Spectris, employing approximately 9,800 people worldwide.
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