Perceptual and Physical Aspects of Musical Sounds

This paper presents the research involved in the elaboration of the timbre model, a signal model which has been built to better understand the relationship between the perception of timbre and the musical sounds most commonly associated with timbre. The elaboration of the timbre model involves an overview of the related topics in many fields. In particular the signal processing, perceptual and physical considerations, which have been taken into account when elaborating the model, are detailed. This includes in particular the timbre perception research and results from physical models of musical instruments. The timbre model is based on a sinusoidal model, and it consists of a spectral envelope, frequencies, and a temporal envelope, which together form the deterministic part of the model, and different irregularity parameters, which form the stochastic part of the model. Many of the parameters of the model (the timbre attributes) are here associated with verbal opposition pairs, such as high-low and dark-bright. An overview is given of the relevant signal processing aspects, the perceptual and psycho-acoustic research with relevance, and the physical reality behind many of the choices made when elaborating the model. The analysis, estimation and understanding of the timbre attributes are related to relevant research, wherever applicable, giving indications on how to improve these issues, evaluate the improvement and relate the improvements to timbre perception.