G.R.A.S. 40AN 1/2" Ext. Polarized Free-field Microphone, Low Frequency Date 10-06-2013. Page 1 of 5 G.R.A.S. 40AN 1/2" Ext. Polarized Free-field Microphone, Low Frequency Sensitivity: 50 mV/Pa Freq resp: 0.5 Hz to 20 kHz Dynamic range: 14 dBA to 146 dB The 40AN is an IEC 61094 WS2F classified ½" externally polarized free-field, low-frequency microphone with rear-venting. It is a high-precision condenser microphone made according to IEC 61094-4 requirements. The 40AN's design is based on the similar G.R.A.S. 40AF ½" free-field microphone, but optimized for low-frequency measurements. The cut-off frequency is as low as 0.5 Hz and obtained by modifying the equalization. Introduction The 40AN is an IEC 61094 WS2F classified ½” externally polarized free-field, low-frequency microphone with rear-venting. Read about the prepolarized equivalent [40AZ]. It is a high-precision condenser microphone made according to IEC 61094-4 requirements. The 40AN’s design is based on the similar G.R.A.S. 40AF ½” free-field microphone, but optimized for low-frequency measurements. The cut-off frequency is as low as 0.5 Hz and obtained by modifying the equalization. 40AN is individually factory-calibrated and delivered with a calibration chart stating its specific open-circuit

G.R.A.S. 40AN 1/2" Ext. Polarized Free-field Microphone, Low Frequency Date 10-06-2013. Page 2 of 5 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 40AN the obvious choice for infra-sound measurements—a fast growing discipline following the need for monitoring and reducing low-frequency noise from, for example, power and production plants and the increasing number of wind turbines. Compatibility The 40AN requires a standardized ½” or ¼” LEMO preamplifier and an...

G.R.A.S. 40AN 1/2" Ext. Polarized Free-field Microphone, Low Frequency Date 10-06-2013. Page 3 of 5 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 calibration equipment. Depending on the use, measurement environment, and internal quality control programs, we recommend recalibrating the microphone at least once a year. Learn more about G.R.A.S.’ calibration services. Specification Open-circuit sensitivity @ 250 Hz (±2 dB) Resonance frequency Dynamic range lower limit...

G.R.A.S. 40AN 1/2" Ext. Polarized Free-field Microphone, Low Frequency Date 10-06-2013. Page 4 of 5 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

G.R.A.S. 40AN 1/2" Ext. Polarized Free-field Microphone, Low Frequency Date 10-06-2013. Page 5 of 5 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...