Psychoacoustics, sound quality and music

In this keynote, relations between psychoacoustics, sound quality, and music are discussed. In the domain of psychoacoustics, a Dynamic Loudness Model (DLM) is presented which can simulate loudness perception of sounds with strong temporal structure for both normal hearing persons and persons with (slight) hearing deficits. Recent results on the hearing sensation pitch strength will be presented and discussed in view of applications both in sound quality design and music. Sound quality is assessed on the one hand for products where it is a genuine feature like musical instruments, and on the other hand where it is just a by-product like Diesel engines or closing car doors. It is shown that the psychoacoustic magnitudes loudness and sharpness can account for largely different aspects like the annoyance of snoring sounds on the one hand and the sound quality of grand pianos on the other hand. The concept of psychoacoustic annoyance based on noise evaluation is contrasted with the concept of sensory pleasantness, anchored in musical acoustics. For questions of sound quality design, an approach incorporating elements of decision tree studies is proposed. The strong ties between psychoacoustics, sound quality and music have been advocated already about 150 years ago by Helmholtz. He postulated that musical consonance is governed by the absence of roughness. These days, roughness is one of the major ingredients for sound quality design. Also, musical dynamics from ppp to fff is reflected in modern category scaling procedures used in psychoacoustics as well as sound quality rating. Moreover, A-weighted level can be misleading with respect to loudness perception for both musical and technical sounds. Therefore, a loudness-thermometer is contrasted with a level-thermometer, including possible cognitive effects of recognizing the sound source.