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The new 47AC Infrasound microphone set

The new 47AC - perfect for infrasound measurements

The increased awareness about infrasound, and the discomfort that noise and low frequencies can bring along, has given rise to new measurement challenges from the aerospace industry to monitoring environmental noise. These challenges require the possibility to measure at extremely low frequencies.

Our answer to these challenges? The new 47AC infrasound microphone set.

Explore the new 47AC

Infrasound graph 

Helping JAXA

Infrasound jaxa

The Japanese Space Exploration Agency

Prior to the launch of the 47AC we have worked extensively with the Japanese Space Exploration Agency (JAXA) to develop testing equipment that enables realistic measurements of sonic booms generated by supersonic airplanes.

Read the JAXA case

Pioneers within infrasound

From a customized solution to a standard product

GRAS are pioneers, when it comes to infrasound measurements. After having worked with a number of partners we have now developed a solution for the market and are introducing the 47AC microphone set.

Contact us for advice


Product benefits

Infrasound jaxa

Why you should choose the 47AC

  • Frequency range from 0.09 Hz to 20 kHz
  • Dynamic range 20 dB(A) to 148 dB
  • Sensitivity 8 mV/Pa
  • The preamplifier has TEDS for automatic sensor identification and reading of calibration data
  • The 47AC set is assembled and calibrated as a complete unit

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