Strutt Help
Sound Level Difference
1/1, 1/3
Strutt|Building Acoustics|Sound Level Difference calculates the sound level difference between a source and receiver room, taking into account the background noise level of the receiver room:
ISO 10140-4 (2010)
Where the background noise level in the receiver room is 15 dB or more below the measured receiver room noise level:
`L=L_(source)-L_(receiver)`
Where the background noise level in the receiver room is 6 - 15 dB below the measured receiver room noise level:
`L=L_(source)-10*log10(10^(L_(recevier)/10)-10^(L_(BGN)/10))`
Where the background noise level in the receiver room is 6 dB or less below the measured receiver room noise level, it shall be clearly indicated in the report that a 1.3 dB correction has been made and these values are the limit of measurement:
`L=L_(source)-1.3`
If the user ticks the "Report Limits of Measurement instead of Level Difference" box, the function will report whether or not a correction to the receiver room level as been applied as follows:
- BGN 15 dB or more below receiver room level: "Valid"
- BGN 6-15 dB below receiver room level: "Correction"
- BGN 6 dB or less below receiver room level: "Limit"
ASTM E336-11
Where the background noise level in the receiver room is more than 10 dB below the measured receiver room noise level:
`L=L_(source)-L_(receiver)`
Where the background noise level in the receiver room is 5 - 10 dB below the measured receiver room noise level:
`L=L_(source)-10*log10(10^(L_(recevier)/10)-10^(L_(BGN)/10))`
Where the background noise level in the receiver room is less than 5 dB below the measured receiver room noise level, it shall be clearly indicated in the report that a 2 dB correction has been made and these values are the limit of measurement:
`L=L_(source)-2`
If the user ticks the "Report Limits of Measurement instead of Level Difference" box, the function will report whether or not a correction to the receiver room level as been applied as follows:
- BGN More than 10 dB below receiver room level: "Valid"
- BGN 5-10 dB below receiver room level: "Correction"
- BGN less than 5 dB below receiver room level: "Limit"
ASTM E336-20
Where the background noise level in the receiver room is 6 dB or more below the measured receiver room noise level:
`L=L_(source)-10*log10(10^(L_(recevier)/10)-10^(L_(BGN)/10))`
Where the background noise level in the receiver room is less than 6 dB below the measured receiver room noise level, it shall be clearly indicated in the report that a 1.26 dB correction has been made and these values are the limit of measurement:
`L=L_(source)-1.26`
If the user ticks the "Report Limits of Measurement instead of Level Difference" box, the function will report whether or not a correction to the receiver room level as been applied as follows:
- BGN 6 dB or more below receiver room level: "Valid"
- BGN less than 6 dB below receiver room level: "Limit"
Comments or suggestions to
strutt@arup.com