3
INFORMATION FOR TYPE APPROVAL
If the device is exposed to mechanical vibration with an acceleration of 1 m/s
2
perpendicular to the mem-
brane plane of the microphone, the lower limit of the linear operating range increases to 75 dB for the
frequencies 31,5 Hz, 63 Hz, 125 Hz, 250 Hz, 500 Hz, 630 Hz, 800 Hz and 1000 Hz, frequency weighting A.
If the device is exposed to mechanical vibration with an acceleration of 1 m/s
2
parallel to the membrane
plane of the microphone, the lower limit of the linear operating range increases to 58 dB for the frequencies
31,5 Hz, 63 Hz, 125 Hz, 250 Hz, 500 Hz, 630 Hz, 800 Hz and 1000 Hz, frequency weighting A.
3.5
Self-generated noise
In a sound field with an insignificant contribution to the inherent noise, levels of
L
AF
<
14
dB
as well as
L
CF
<
16
dB
are to be expected.
The electrical noise inherent in the preamplifier (terminated with spare capacity and
50Ω
at the input) will
produce
L
AF max
<
14
dB
as well as
L
CF max
<
20
dB
in the display device.
3.6
Linear operating ranges
The operating ranges given below are only valid for calibrated devices! The starting value for each level
linearity test is 94 dB at 1 kHz.
Frequency max in dB(A) min in dB(A) Range in dB(A)
31,5 Hz
100
25
75
1 kHz
140
25
115
4 kHz
140
27
113
8 kHz
139
27
112
12,5 kHz
135
27
108
Table 3.9: Linear operating ranges A-weighted
Frequency max in dB(C) min in dB(C) Range in dB(C)
31,5 Hz
137
62
75
1 kHz
140
30
110
4 kHz
138
30
108
8 kHz
137
30
107
12,5 kHz
133
30
103
Table 3.10: Linear operating ranges C-weighted
3.6.1
Level linearity range
The following table 3.11 contains the measurement ranges for A-weighted sound levels and the C-weighted
peak sound level for microphone sensitivity of 50 mV/Pa.
Fast/Slow/Leq in dB(A) L
AE
in dB(A) L
Cpeak
in dB(C)
25. . . 140
ab 25
37. . . 143
Table 3.11: Level linearity ranges for A-weighted sound levels and C peak
Manual Tango_Plus
40 of 47
SINUS Messtechnik GmbH
