Sound Recording Range Calculation; Quality - Larson Davis SoundAdvisor 831C Reference Manual

18.7.1 Sound Recording Range Calculation

Table 18.2 Sound Recording Range Calculator
Range
Instrument Gain
Upper Limit
Lower Limit Level
Sound Recording Range

18.7.2 Quality

SoundAdvisor Model 831C
When the peak overload, range, and gain have been set for the
SoundAdvisor, the sound recording range can be calculated using the
table below:
High
0 dB
Peak Overload Peak Overload
- 0 dB
Lower Limit Level — Upper Limit
For example, if the following settings were active for a measurement
setup:
• Range: High
• +20 Gain
• Peak Overload: 143.3
Then the Sound Recording Range would be 30.3 dB — 123.3 dB.
The quality of the sound recording depends on the levels of sound
being recorded and the instrument gain and range used in the setup. If
the sound level exceeds the upper limit, clipping will occur. If the sound
level drops below the lower limit of the sound recording range, then its
signal will be lost in the noise during playback. Because of this, the
selection of the gain and range should be made with the characteristics
of the anticipated sound in mind.
When measuring very loud noise levels (gun blasts, sonic booms, space
shuttle lift off) use the High range. When trying to identify quiet noise
sources (crickets, airplanes flying at 3000 ft, national park soundscape
studies, people talking in the vicinity of the microphone) and don't
mind very loud noises being clipped (distorted), use the Normal range.
Sound Recording Range
+20 dB 0 dB
Peak Overload
- 20 dB - 31 dB
Upper Limit - 93 dB
Normal
+20 dB
Peak Overload
- 51 dB
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