G.R.A.S. 40AZ 1/2" Prepolarized Free-field Microphone, Low Frequency Date 10-06-2013. Page 1 of 6 G.R.A.S. 40AZ 1/2" Prepolarized Free-field Microphone, Low Frequency Sensitivity: 50 mV/Pa Freq resp: 1 Hz to 20 kHz Dynamic range: 14 dBA to 134 dB The 40AZ is an IEC 61094 WS2F classified ½" prepolarized free-field, low-frequency microphone with rear-venting. Its design is based on the similar G.R.A.S. 40AE ½" free-field microphone, but optimized for low-frequency measurements. The cut-off frequency is as low as 0.5 Hz and is obtained by modifying the equalization. Introduction The 40AZ is an IEC 61094 WS2F classified ½” prepolarized free-field, low-frequency microphone with rear-venting. Read about the prepolarized equivalent [40AN]. It is a high-precision electret condenser microphone made according to IEC 61094-4 requirements. The electret technology for microphones was introduced in the beginning of the 1960’s and has been continuously improved over the years. At G.R.A.S., we have developed and refined our own techniques. This guarantees that our prepolarized microphones are as stable and robust as our traditional, externally polarized versions in daily use scenarios. Learn more about our prepolarized microphones. The 40AZ’s design is based on the similar G.R.A.S. 40AE ½” free-field microphone, but optimized for

G.R.A.S. 40AZ 1/2" Prepolarized Free-field Microphone, Low Frequency Date 10-06-2013. Page 2 of 6 low-frequency measurements. The cut-off frequency is as low as 0.5 Hz and is obtained by modifying the equalization. 40AZ is individually factory-calibrated and delivered with a calibration chart stating its specific open-circuit sensitivity, pressure, and corrected free-field frequency responses. Typical applications and use The low-frequency property combined with its high sensitivity and robust design make 40AZ the obvious choice for infra-sound measurements—a fast growing discipline following...

G.R.A.S. 40AZ 1/2" Prepolarized Free-field Microphone, Low Frequency Date 10-06-2013. Page 3 of 6 Service If you accidentally damage the diaphragm on a G.R.A.S. 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. Learn more about G.R.A.S.’ service program. Calibration Before leaving the factory, all G.R.A.S. microphones are calibrated in a controlled laboratory environment using traceable...

G.R.A.S. 40AZ 1/2" Prepolarized Free-field Microphone, Low Frequency Date 10-06-2013. Page 4 of 6 Temperature coefficient @250 Hz [dB/°C / dB/°F] Static pressure coefficient @250 Hz Humidity range non condensing Influence of axial vibration @1 m/s² CE/RoHS compliant, WEEE registered Weight System Setup Compatibility The 40AZ requires a standardized ½” or ¼” CCP preamplifier and an input module that supports this technology. The G.R.A.S. CCP preamplifiers connect to the input module either with BNC to BNC, SMB to BNC, or Microdot to BNC cables. If a CCP input on the analyzer is not available,...

G.R.A.S. 40AZ 1/2" Prepolarized Free-field Microphone, Low Frequency Date 10-06-2013. Page 5 of 6 To benefit from 40AZ’s low-frequency capabilities, the preamplifier must accommodate for the microphone’s low cut-off frequency and not become the limiting part of the measurement chain. For that purpose, we have developed the high-impedance G.R.A.S. 26CG 1/4" CCP Preamplifier with Microdot connector, low-frequency. Tegning: Typical Setup (blokdiagram) This example shows a typical setup using 40AZ and the 26CA ½” CCP Preamplifier and a CCP compatible input module with BNC connector. Note: Preamplifier...

G.R.A.S. 40AZ 1/2" Prepolarized Free-field Microphone, Low Frequency Date 10-06-2013. Page 6 of 6 Tradition Since the establishment in 1994, G.R.A.S. have been 100% dedicated to developing and manufacturing high-quality measurement microphones and related acoustic equipment. Founded by the Danish acoustics pioneer Gunnar Rasmussen who for more than 60 years has contributed to the world of sound and vibration with his unique ideas and designs. From the first reproducible 1” condenser measurement microphone that enabled quality measurements and instrumentation for acoustic calibration, Mr. Rasmussen’s...