15 Technical features
15.1Microphone and windscreen of the class 1 DB300 sound level meter
The instrument is equipped with an electret microphone with an integrated preamplifier of standardized diameter of ½ inch. Fixed at the
top of the sound level meter, it gives to the group (microphone and housing) free field features compatible with standards.
15.1.1 Sheet
Brand: PCB - 377B02
Type: condenser with electret
External diameter of the grid: 13.2 mm (½ inch)
Nominal sensitivity for preamplifier output: 45 mV/Pa
Equivalent capacity: about 12 pF
15.1.2 Normal frequency response in free-field
15.1.3 Windscreen
B-DB23 windscreen creates modifications of free field response that comes in addition to initial features of the microphone on the
housing. The whole stays compliant to requirements class 1 reference standard. So, when using the windscreen, there is no need to
take into account a correction term free field.
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Technical features
Free-field frequency response type – incidence 0 ° on the sound level meter housing - template class 1 NF EN 61672-1
Free-field response microphone type +B-DB23 – template class 1 EN NF 61672-1
dB
Hz
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