International audienceIn this study, a finite element model is used to simulate the impact of wood modifications on the dynamical behaviour of a violin. Chemical and fungal modifications of the wood selected for violins (tonewood) are considered. In addition, the impact of spruce indented rings anatomic singularities is also studied. Models are used to compute modal bases up to 4000 Hz, and eigenfrequencies, eigenvectors and bridge admittance are used to compare different dynamical behaviours. The impact of wood modifications over the geometric tolerances inherent to instrument makers methods is discussed. This study shows that some modifications or anatomic singularities are not sufficiently efficient to be observed reliably over the geometric uncertainties. In contrary the fungal treatment method also known as mycowood sufficiently modifies the dynamical behaviour to to overcome the luthiers tolerances. Moreover, results give a wood modifications threshold, which can be used as a support for further wood modification methods