Introduction

Musicians have been using filters for thousands of years to shape the sounds of their art in various ways. For example, the evolution of the physical dimensions of the violin constitutes an evolution in filter design. The choice of wood, the shape of the cutouts, the geometry of the bridge, and everything that affects resonance all have a bearing on how the violin body filters the signal induced at the bridge by the vibrating strings. Once a sound is airborne there is yet more filtering performed by the listening environment, by the pinnae of the ear, and by idiosyncrasies of the hearing process.