Recent developments in sound quality evaluation

This keynote introduces various contributions to a structured session on sound quality organized by the present author. In the last decade, basic research as well as practical applications of sound quality increased substantially. This holds true for sound quality of emissions e.g. in product sound as well as for sound quality of immissions e.g. in the environment. For product sound, two cases of sound quality are considered: one, where sound quality is the dominant, generic feature of a product like musical instruments or loudspeakers, and a second, where sound quality is a by-product like the sound of Dieselengines or to give a more exotic example the sound quality of snoring. As concerns sound immissions, wanted sounds typical for a soundscape and unwanted sounds typical for noise immissions can be distinguished. However, also sounds blending perfectly into a soundscape like the noise of a chain saw in the soundscape of a forest, may be pretty annoying. For both product sound and sound quality of the environment, influences of the meaning of sounds have to be considered. Additional extra-aural effects like the image of brand names or audio-visual interactions can significantly influence sound quality judgements.