Typical applications and use
- Flush mounting in confined spaces
- Flush mounting in clay models
- Ground array measurements
- General noise measurements
With a height (to the diaphragm) of only 8 mm, 47AX is suitably designed for flush mounting in plates in ground array applications and other applications with size constraints. The microphone is a prepolarized pressure microphone with a dynamic range from 22 dB to 146 dB and a frequency range from 3.15 Hz to 20 kHz. The built-in preamplifier is a low noise constant current power (CCP) type, with a built-in TEDS circuit for automatic transducer identification. The set has an integrated 1.5 m cable with Microdot connector plus an adapter for BNC cable.
Flush-mounting is ideal where holes can be made in the structure, such as a clay model, to accommodate the front-vented 47AX. A rear-vented version is also available, the 47AX–S1.
It is included with the G.R.A.S. 67BX Ground Array Set, which has a 400 mm diameter mounting plate.
The 47AX is based on the IEC 61094 standard for measurement microphones.
|Frequency range (±1 dB)||Hz||5 to 12.5 k|
|Frequency range (±2 dB)||Hz||3.15 to 20 k|
|Dynamic range lower limit with G.R.A.S. preamplifier||dB(A)||22|
|Dynamic range upper limit with G.R.A.S. CCP preamplifier||dB||150|
|Set sensitivity @ 250 Hz (±2 dB)||mV/Pa||12.5|
|Temperature range, operation||°C / °F||- 30 to 70 / - 22 to 158|
|Temperature range, storage||°C / °F||- 40 to 85 / - 40 to 185|
|Static pressure coefficient @250 Hz||dB/kPa||-0.008|
|Humidity range non condensing||% RH||0 to 100|
|Humidity coefficient @250 Hz||dB/% RH||< 0.1|
|Influence of axial vibration @1 m/s²||dB re 20 µPa||66|
|TEDS UTID (IEEE 1451.4 )||27 v. 1.0|
|Connector type||Microdot 10/32|
|CE/RoHS compliant/WEEE registered||Yes/Yes/Yes|
|Weight||g / oz||15 / 0.529|
Typical frequency response
|G.R.A.S. RA0221||Pistonphone calibration adapter|