Roughness calculation utilizing envelope waveforms

Psychoacoustical roughness refers to the tactile percept of rough surfaces related to an auditory sensation. The presence of roughness influences many sound-quality aspects e. g. annoyance, comfort or the sportive character in a vehicle interior sound. A reliable calculation method for roughness predictions is a very powerful tool in processes like sound design or sound analysis. Roughness perception depends on many acoustical signal parameters like modulation depth, sound level, audio frequency, modulation frequency or the shape of the modulating envelope waveform, which have not been taken into account in previous calculation methods. Also, the temporal regularity of occurring modulations strongly affects the amount of perceived roughness. A new algorithm for roughness calculations based on a generalized hearing model will be presented. It takes into account all these dependencies for synthetic signals as well as several sound properties occurring in natural sounds. During development, the focus was set on the roughness of interior vehicle noises as roughness can be seen here as a sound feature governing attributes like "dynamic", "sportive" or "comfortable".