On the determination of transmission loss and facade sound insulation by means of impulse response measurements

The research described in the paper reports the determination of transmission loss and facade sound insulation by applying the impulse response method. The work started from the draft ISO/DIS 18233 on the "application of new measurement methods in building and room acoustics". From the measured impulse response it is in fact possible to determine the energy level, corresponding to a steady noise, and the reverberation time through the calculation of the Schroeder integral plot. The required parameters can then be calculated by using the relationship proposed by the ISO 140 series. The experimental measurements were carried out using the technique of exponential Sine Sweep. Some preliminary tests were made using also the MLS and the balloon-bursting techniques. The results obtained were analysed and compared with those produced with the traditional technique.