Prepolarized Pressure Microphone GRAS 40BD-FV 4Hz~70kHz

Introduction

• The 40BD-FV is an IEC 61094 WS3P ¼” prepolarized pressure microphone with front venting. Read about the externally polarized equivalent [ GRAS 40BP-FV]
• It is a high-precision condenser microphone made according to IEC 61094-4 requirements. Its low sensitivity makes it ideal for sound measurements at high frequencies and high sound pressure levels of up to 174 dB. Its small size reduces the effects of diffraction and reflections around the microphone, resulting in a frequency range that extends up to 70 kHz.
• 40BD-FV is individually factory-calibrated and delivered with a calibration chart stating its specific open-circuit sensitivity and pressure frequency response.

Typical applications and use

• The 40BD-FV is ideal for sound pressure measurements, as well as high frequency and high level pressure measurements. It is suitable for general purpose acoustic measurements in couplers and at boundaries. 40BD-FV is included in the GRAS 46BD-FV ¼” Pressure microphone set.

Compatibility

• The 40BD-FV requires a standardized ½” or ¼” CCP preamplifier and an input module that supports this technology with a BNC, SMB, or Microdot connector.

System verification

• For daily verification and check of your measurement setup, we recommend using a calibrator like GRAS Sound Level Calibrator 42AG.
• For proper sensitivity calibration, we recommend using a pistonphone like GRAS Intelligent Pistonphone 42AP.

Service

• If you accidentally damage the diaphragm on a GRAS microphone, we can—in most cases—replace it at a very reasonable cost and with a short turn-around time. This not only protects your investment, but also pleases your quality assurance department because you don’t have to worry about new serial numbers, etc.

Calibration

• Before leaving the factory, all GRAS microphones are calibrated in a controlled laboratory environment using traceable calibration equipment.
• Depending on the use, measurement environment, and internal quality control programs, we recommend recalibrating the microphone at least once a year.