Larson Davis 831C-FFT, Reference Manual

Page: 62 / 254

SoundAdvisor Model 831C Creating a Custom Setup File On the Meter 57
FIGURE 6-4
Setup Manager: SLM Tab
1.
Select a Frequency Weighting , Detector , and Peak
Weighting . Your choice for the Detector setting
communicates to the meter hardware how quickly it
needs to begin measuring the current sound. See also
“Detector” in the
Appendix C Glossary on page C-1.
2.
If you’re unsure which Integration Method to
choose, select
Linear
, and see the section below called
About Integration Methods .
3.
Select the 20 dB Gain checkbox when measuring
low-level sounds, or when the sound level is close to
the background noise level. For more information, see
the section below called About Using the Gain
Feature .
4.
The
Running Leq Period
is used when the Event
History option (831C-ELA) is purchased and enabled on
your meter. In this example, the period is the Leq of the
last 1200 seconds of the measurement run time. For
more information, see Module 17 Using Event History
Firmware .
About Using the Gain Feature
When using a microphone with sensitivity of 50 mV/Pa, the input overload occurs
approximately as shown in Table 6.1 .
About Integration Methods
Although the 831C measures levels at all 3 detector and frequency weighting settings
according to your selection, some features require a single combination. The level defined
by the detector and frequency weighting you select is used for the computation of Ln,
Exceedances, Sound Exposure, and Sound Events. However, some features may not be
available for Exponential Integration Method. See
Appendix C Glossary on page C-1.
Step 5.
If OBA is enabled for your meter, use the
right softkey
(
//*
) to navigate to
the
OBA
tab as shown in Figure 6-5 .
1.
3.
4.
2.
Table 6.1 OBA Overload Levels
Input Gain, dB OBA Range Overload Level, dB peak
0 High 143
20 High 123
0 Normal 110
20 Normal 90