SmartSMS User Manual
Soft dB inc.
User Manual
p. 100
Appendix B: Sound level meter with limited 50 dB dynamic range
Some sound level meters (SLM) have a limited dynamic range (example 50 dB
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), and cannot cover
the levels from 35 dBA (typical background noise level) to 94 dBA (standard calibration level) for
one range selection. The solution is to change the dynamic range between the input calibration and
the measurements. In this case, the user must specify the dynamic range difference in the interface
used to determine the reference sensitivity. Use the Ref. Input Sensitivity button to launch this
interface. The following figure presents input parameters with the Calibration and measurement
dynamic difference (dB) control.
Figure 97: Reference input sensitivity adjustment interface
To determine the value of the difference, subtract the dynamic range used for the measurement
from the dynamic range used for the sensitivity adjustment. For instance, if the dynamic range used
for the sensitivity adjustment is 50 to 100 dBA and the dynamic range used for the measurement is
30 to 80 dBA, the difference is 20 dB.
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Note that the sound level meter used should be able to measure a background noise level of 35 dBA and have a dynamic
range of at least 50 dB.
