Numerical and Experimental Study of the Effect of the Bridge of Sarasvati Veena on its Timbre

Abstract

The Sarasvati Veena is an Indian stringed musical instrument with a curved bridge having a parabolic equation. We study the effect of such a bridge on the timbre of the instrument. We model the interaction of the vibrating string with the bridge as frictionless impact. So we implemented an energy-conserving method where string–bridge interaction is modelled with a penalty approach. We solve the resulting Hamilton’s equations numerically. Simulations are performed with different values of bridge parameters, namely slope and curvature. The numerical model is validated by comparison with experimental analysis. We isolate the contribution of the bridge by mounting it on the sonometer in place of one of its knife-edges and a mechanism is provided on the sonometer to change the bridge slope. We mounted the sonometer on foam to minimize the effect of other structural parameters. The typical Veena timbre shows sustain of most harmonics and the revival of higher harmonics with time. These features are attributed to the shape of the metallic layer at the top of the Veena bridge, its slope and curvature. Our model also shows these features, which are further corroborated by the experiment.