China
Africa
Explore chapters and articles related to this topic
Acoustics and acoustic devices
Published in Michael Talbot-Smith, Audio Engineer's Reference Book, 2013
Bob Walker, Talbot-Smith Michael, Chris Woolf, John Borwick, Francis Rumsey, John L. Andrews, Peter Baxandall, Alan Tutton
In the laboratory, the sound isolation of a partition is measured as the difference in levels between a source room and an adjoining receive room, with the test partition in the common surface. To make comparisons possible between different laboratories, the effects of the area of the partition and the acoustic conditions of the rooms are removed numerically. The resulting normalized value for the sound isolation is called the �sound reduction index� (SRI). For practical design to a criterion calculated as above, on the required sound level differences (SLD) the corrections appropriate to the particular design must be reapplied to the SRI figures to obtain the actual differences likely to be achieved in practice.
Thermal and sound insulation performance assessment of vacuum insulated composite insulation panels for building façades
Published in Advances in Building Energy Research, 2021
Sound reduction index () is measured at various frequencies, generally one-third octave band between 100 and 3150 Hz. However, a single number rating, i.e. weighted sound reduction index () is required for quantitatively measuring the sound insulation properties of each panel. can be calculated using the procedure described in BS EN ISO 717-1 (BSI, 2013b) where measured results are compared against the reference curve given in BS EN ISO 717-1. The reference curve is shifted towards the measured curve in increments of 1 dB until the total of unfavourable deviations is as large as possible but not more than 32 dB. An unfavourable deviation at a particular frequency takes place when the experimental value is lower than the reference curve value. The value of shifted reference curve value at 500 Hz frequency is considered as the weighted sound reduction index, .
Thermal and sound insulation of lightweight steel-framed façade walls
Published in Science and Technology for the Built Environment, 2019
Eduardo Roque, Paulo Santos, Andreia Carvalho Pereira
In this section an analysis of the sound reduction index (R) in one-third-octave bands for the several LSF models is assessed. Figure 8 presents the results for the three LSF construction types. In this figure, the plots displayed on the left (column 1) relate to the partitions with the studs and those on the right (column 2) display the results for walls without the steel frame.