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4.5
Measurements of low-level sounds
The self-generated noise level for the most sensible ranges of S50 is
below (but near to) 20dBA or 23dBC. This must be considered when
measuring low-level sounds. The self-generated noise and the
measured sound can be considered as uncorrelated and don’t add
directly to each other. The self-generated noise level for the less
sensible ranges is higher, but is at least 5 dB below the low end of
the range.
Measured level = 10
*
log
10
(10
(noise/10)
+ 10
(sound/10)
) [dB]
Example:
noise level = 20 dB, sound level = 23 dB
measured level = 24.8 dB
Influence by the self-generated noise level, as function of the difference between
the sound level and the noise level.
Summary of Contents for 080-02850-0
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