BRUEL & KJAER 4188 - Page 27

Chapter 2 — Prepolarized Free-field
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Frequency Response
Falcon™ Range of Microphone Products
Microphone Handbook
Brüel & Kjær
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2.3.6 Random-incidence Response
A microphone’s response in a diffuse sound field is equivalent to its random-inci-
dence response. The microphone’s random-incidence correction curves are shown in
Fig.2.6, Fig.2.8 and Fig.2.10. These corrections are added to the microphone’s actu-
ator response obtained using Electrostatic Actuator UA0033 in order to determine
the random-incidence response. The typical random-incidence with and without the
protection grid, and with Random Incidence Corrector DZ9566 are shown in
Fig.2.12, Fig.2.13 and Fig.2.14, respectively.
The random-incidence corrections are calculated from the free-field corrections
measured in 5° steps according to Draft IEC1183–1993.
Fig.2.12 Typical random-incidence response for the microphone with Protection Grid DD0525
Fig.2.13 Typical random-incidence response for the microphone without protection grid
940934/1e
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Frequency (Hz)
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940885/1e
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