Following previous investigation, carried out at the University of Parma in 1999 and 2000, LAE (Laboratory of
Acoustics and Electroacoustics) started a new measurement campaign to compare with the original results on the
same type of diffusor panels, to verify AES-4id-2001 measurement standard and to investigate the nature of
scattering phenomena in more detail. Measurements are conducted on the floor of a large closed space to obtain a
reflection free time window, long enough to study the first reflection from the panel; the use of sine sweep excitation
signals instead of the recommended MLS ones permits to ameliorate the acquisition process. The present article
discusses research background studies and the results from the first round of measurements
