Larson Davis SoundAdvisor 831C Reference Manual page 195

11885.02
12589.25
13335.21
14125.38
14962.36
15848.93
16788.04
17782.79
18836.49
19952.62
f) Linear Operating Range
Table B.5 Linearity Range (Nominal Values)
Weighting Gain
A 0 dB
20 dB
C 0 dB
20 dB
Z 0 dB
20 dB
g) Linear Measurement Starting Point
Table B.6 Linear Measurement Starting Point
Gain 31.5 Hz
0 dB 74.5 dB
20 dB 54.5 dB
h) Electrical Insert Signals
The electrical design of the input device to insert electrical signals into the preamplifier is a series 12pF ± 5%
capacitor. The Larson Davis ADP090 is used for this purpose. The ADP090 is also use for noise floor measurements
by attaching the included BNC short on the front of the ADP090.
i) Self Generating Noise in Low Level Sound Field
Table B.7 SLM Noise Levels (Sheet 1 of 2)
Self Generated Electrical
SoundAdvisor Model 831C
-0.50
-0.57
-1.17
-1.59
-2.20
-3.05
-3.88
-5.38
-6.56
-8.15
31.5 Hz 1 kHz
Lower Upper Lower
22.6 100.5 22.6
18 80.5 18
25 137.5 25
24 117.4 24
36 140.5 36
35 120.5 35
1 kHz
114 dB
94dB
Noise
Weighting Typical (dB)
A
-4.31
-4.41
-4.64
-4.95
-5.41
-6.30
-7.46
-8.87
-10.06
-11.24
4 kHz
Upper Lower Upper
140 22.6 141
120 18 121
140.5 25 139.7
120.4 24 119.6
140.5 36 140.5
120.5 35 120.5
4 kHz
115 dB
95 dB
0 dB Gain
Max (dB) Typical (dB)
10 12
-2.90
-2.76
-2.90
-3.41
-4.07
-4.98
-6.31
-7.91
-9.40
-10.80
8 kHz
Lower Upper Lower
22.6 138.9 22.6
18 118.9 18
25 137.4 25
24 117.4 24
36 140.5 36
35 120.5 35
8 kHz 12.5 kHz
112.9 dB 109.7 dB
92.9 dB 89.7 dB
20 dB Gain
Max (dB)
6 9
0.30
0.30
0.30
0.30
0.30
0.30
0.30
0.30
0.30
0.30
12.5 kHz
Upper
135.7
115.7
134.3
114.2
140.5
120.5
B-9