Typical applications and use
The G.R.A.S. 40PS is a low-profile, light surface microphone for general purpose measurements on planar and curved surfaces within aeroacoustics, wind tunnel applications and large arrays.
Its frequency range extends from 10 Hz to 12 kHz and its dynamic range is from below 27 dBA to 145 dB.
It has an integrated CCP preamplifier with TEDS according to IEEE 1451.4 for remote identification and reading of calibrated sensitivity.
It requires a constant-current power supply such as the G.R.A.S. 12AL 1-Channel CCP Power Module with A-weighting filter, or any other compatible constant-current power supply.
Pressure equalisation is via a vent placed at the front of the microphone just by the side of its diaphragm. This makes it suitable for use in conditions with rapid static pressure changes, for example on aircraft or on road vehicles in mountainous country.
Together with any of the G.R.A.S. mountings, the profile of the surface microphone will not exceed 3 mm.