Larson Davis SoundAdvisor 831C Reference Manual page 185

Instrument Noise Levels With OBA, by Preamp
FIGURE A-2
40.0
30.0
20.0
10.0
0.0
-10.0
1
SoundAdvisor Model 831C
Overall Metrics:
OBA Overall Equivalent Level Spectrum
OBA Overall Maximum Level Spectrum
OBA Overall Minimum Level Spectrum
Statistics are sampled every 100ms from the selected OBA frequency weighting
and time weighting into 0.1 dB wide amplitude classes, as shown in Table A.18.
Table A.18
1
2
3
4
5
6
The following charts show the 831C instrument noise levels for the OBA filter With
PRM831 and Direct Input.
Self-Generated Noise Levels for 1/1 Octave Filter With PRM831
10
100
Units
L dB
ωn1(f)
L dB
ωn2(f)
L dB
ωn3(f)
L dB
ωn4(f)
L dB
ωn5(f)
L dB
ωn6(f)
1000
Linear Exponential
L L
ωeq(f) ωeq(f)
L L
ωmax(f) ωmax(f)
L L
ωmin(f) ωmin(f)
High +0dB
High +20dB
Normal +0dB
Normal +20dB
10000
Units
dB
dB
dB
A-21