Testing the airborne sound insulation of reduced size baffles with different dimensions

The article discusses the requirements for determining airborne sound insulation according to ISO 10140-2, which involves measuring sound pressure levels in the source (L1) and receiving (L2) rooms, as well as reverberation time measurements in the receiving room. The size of the free test opening and the equivalent sound absorption area in the receiving room affect the value of L2. While ISO 10140-5 specifies the dimensions of a full-size test opening, reduced-size openings can also be used. However, testing reduced-size baffles with specific dimensions may be necessary, and measurements on rectangular-shaped baffles may yield higher sound reduction indices than square-shaped ones. The article presents a comparative analysis of the spectral characteristics of different types of single homogeneous baffles with various dimensions using experimental methods. It examines the measurement methodology's influence on determining sound insulation spectra and the weighted sound reduction index Rw. The article also calculates the combined uncertainty in determining the sound insulation properties and partial uncertainties in determining L1 and L2.