There are not many of so complex instruments like the piano, and as most of the other ones the whole mechanical system is a result of empirical improvements. The well-known piano sound is influenced by many parameters.
A physical model-based representation of an instrument could be useful in two different aspects. In one hand the model-based sound synthesis is a competitive alternative to the nowadays dominant sample-based sound synthesis, because through a parametrised physical model we receive quite infinite number of existing and virtual instruments. In the other hand these models could also play an important role in improving and perfectionating the instruments; a precise model could be a great support in piano manufacturing.
In my work I deal with a complex but simplified physical model of the main mechanical elements which take part in the sound production of the piano. Besides the mechanical features of hammers and strings, the soundboard plays the most important role in the sound production process. In this study I describe some characteristics of nonlinear hysteretic hammer felt models, the main problems and benefits of coupled digital waveguides in case of string modelling, and some effects of the orthotropic numerical soundboard model on the inside-board coupling and on the radiated sound. The model deals with the whole vibration propagation chain from the hammer impact on multiple strings to the sound radiation.