Norsonic nor1217, Инструкция по эксплуатации

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13 Norsonic Nor1217
Instruction Manual
Frequency response
The figure below shows the typical frequency re-
sponse for sound approaching the microphone in two
directions. The response marked “Vertical” is the re-
sponse for sound approaching the microphone from
above along the bird spikes, when the microphone is
in the recommended vertical direction. The response
marked “Horizontal” is the response for sound ap-
proaching the microphone in a horizontal direction
when the microphone is mounted in the same recom-
mended vertical direction.
Due to the lower sensitivity for higher frequencies, as
shown on the figure, it is recommended to correct the
frequency response to ensure that the response is
within the requirement for Class 1 sound level meters
specified in the international standard IEC 61672-1.
10 100 1k 10 k 20 k
30 −
25 −
20 −
15 −
10 −
5 −
0
5
10
Vertical
Horizontal
Sensitivity level [dB]
Frequency [Hz]
When the microphone system is used in connection
with the precision sound analyser Nor140 (for program
version 3.0 and above), just select 1214/1216/1217
Vertical or Horizontal in the input setup menu to enable
the right settings. Turn the polarization voltage
On
if
you use a Nor1225 and
Off
if you use a Nor1227.
When used with Nor118 we recommend the following
corrections:
Vertical: Random response correction (R) and
Windscreen correction (W)
Horizontal: Random response correction (R)
Please note that the frequency compensation applied
using the Nor118 does not fulfil the class 1 require-
ments, but is just a “best fit” method.