SoundAdvisor Model 831C
A-14
FIGURE A-5
Self-generated noise levels for 1/3 octave filters with direct input
OBA Measurement System
Integration Method
: Follows setting for SLM
Frequency Weightings
: Independent of setting for
SLM, selected frequency weighting (A, C or Z)
indicated by
Time Weightings/Detectors
: Follows setting for
SLM, time weighting (S, F or I) indicated by
OBA Measurements
Instantaneous “Live” Metrics
:
For display and
profile graph, not stored with measurement.
Overall Metrics
:
Percentile Spectrum Levels
, uses same
percentages n1 through n6 selected in SLM, 0.01 to
99.99%
Statistics are sampled every 100ms from the
selected OBA frequency weighting and time
weighting into 0.1 dB wide amplitude classes
-30.0
-20.0
-10.0
0.0
10.0
20.0
30.0
40.0
50.0
1
10
100
1000
10000
Direct 1/3 OBA Noise Floor
High +0dB
High +20dB
0dB
20dB
Linear
Exponent
Units
OBA Live Equivalent
Level Spectrum, 1s
L
ω
eq(f)
L
ωƬ
eq(f)
dB
Linear
Exponential
Units
OBA Overall Equivalent
Level Spectrum
L
ω
eq(f)
L
ωƬ
eq(f)
dB
OBA Overall Maximum
Level Spectrum
L
ω
max(f)
L
ωƬ
max(f)
dB
OBA Overall Minimum
Level Spectrum
L
Ƭ
min(f)
L
ωƬ
min(f)
dB
Units
1
L
ωƬ
n1(f)
dB
2
L
ωƬ
n2(f)
dB
3
L
ωƬ
n3(f)
dB
4
L
ωƬ
n4(f)
dB
5
L
ωƬ
n5(f)
dB
6
L
ωƬ
n6(f)
dB
