Sound field diffusion by number of peak by continuous wavelet transform

The number of peak (Np) in the impulse response signal (IRs) captured for the real hall have been investigated and measured by using continuous wavelet transform (CWT). Np has a relationship with perceptual diffusion as an objective characteristic that is influenced by walls scattering elements. In addition, as measuring diffuse sound fields, the CWT coefficients are used for detecting the diffusive sound. Based on the absolute coefficient values calculated from CWT analysis, a practical method of counting reflections is considered. These reflections are specified as diffusive or specular base on their similarity with the mother wavelet. Temporal and spatial representation of absolute values of CWT is presented. Auditory experiments using a paired comparison method were conducted to gauge the relationship between the Np and perceptual sound field diffusion. It is revealed that a dominant factor influencing the subjective preference in the hall was the Np that varied with different wall surface treatments.