Technical Booklet G Resistance to the Passage of Sound·Page 119·B2.4
Source room measurement spectrum requirements
The difference between average sound pressure levels in adjacent one-third octave bands in the source room must not exceed 6 dB, otherwise the source spectrum should be adjusted and measurements repeated.
For the source room measurements, the difference between the average sound pressure levels in adjacent one-third octave bands should be no more than 6 dB. If this condition is not met, the source spectrum should be adjusted and the source room measurement repeated. If the condition is met, the average sound pressure level in the receiving room, and hence a level difference, should be determined.
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