Larson Davis 831C-FFT, Reference Manual

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SoundAdvisor Model 831C SoundAdvisor 831C Display In SLM Mode 39
About the Normalized Octave Band Page (Overall Page)
TAKE NOTE
This feature requires the 831C-OB3 firmware option, and OBA enabled in the
measurement setup file.
The user-defined references are determined at this location: Tools
3

System
Properties  Reference Spectra .
FIGURE 4-13 Overall Tab: Normalized Octave Bands
1.
Highlight the bands to change the selected frequency
by using the left and right arrow keys and Enter
5
.
2.
Press Enter
5
to jump from Ref, Set Reference, and
back to Octave labels.
3.
When you change the weighting and reference, reset
Spectra values by selecting Set Reference .
Table 4.2 Overall Octave Band Colors
L
eq
“Leq” is the average sound level of the highlighted
frequency band for the duration of the measurement.
L
max
L
max
is the maximum sound level of the highlighted
frequency band. The maximum spectrum is determined by
the Max Spec setting.
Bin Max : When set to Bin Max, this value is the maximum
value which occurred during the entire measurement for
that frequency band. Since individual frequency bands
may reach their maximum levels at different times, this
spectrum might be one which never occurred at any
instant during the measurement period.
At Max : When set to At Lmax, this value is the
instantaneous spectrum at the moment when the
broadband maximum occurred (such as LSmax).
L
min
L
min
is the minimum sound level of the highlighted
frequency band for the duration of the measurement. Since
individual frequency bands may reach their minimum
levels at different times, this spectrum might be one which
never occurred at any instant during the measurement
period.
1.
3.
2.