Svantek SVAN 979 - Description of the Decay Curve Recording in Different Measurement Methods

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SVAN 979 User Manual - Appendixes
Fig 4. The RT 30 evaluation
E.3. DESCRIPTION OF THE DECAY CURVE RECORDING IN DIFFERENT MEASUREMENT METHODS
➢ DECAY method
This RT 60 measurement method requires omnidirectional sound source which emits pink noise in appropriate
frequency band. The most critical parameter of the omnidirectional sound source is emitted sound pressure
level as it was mentioned in the beginning of the appendix.
The graphical illustration of the data recording in this method is presented in Figure 5.
Fig 5. Data recording in the decay method of the reverberation time evaluation
t [s]
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[dB]
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4
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1
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4
5 dB
noise
margin
linear approximation
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3
30 dB
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[dB]
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e
t
s
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2
t
trig
10 dB
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1
registration time
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off
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on
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3