Analysis of the Signal Complexity in Sitar Performances

Abstract

The sitar is perhaps the most well known of the Indian plucked string musical instruments. It has a varying number of strings but 16-20 is usual. When played by an expert, the sitar produces a melodious sound effect. The mode of attachment of strings and/or the interaction of the large number of strings, some of them being playing strings, some drone and others sympathetic, create the total acoustic environment, which also includes the global resonance structure of the instrument. This creates a sound whose complexity is difficult to model by usual mathematical methods.Fractal dimension is an effective tool for analysis in such cases. In the present paper D 0 (fractal dimension), D 2 (correlation dimension) and also the higher moments are studied for acoustic signals obtained from actual sitar performances. Four such performances are used for the present study. The obeying of power law indicates the presence of non-linearity in the production system. The presence of multifractality is noticed through an examination of relationship between q and D q and the functional relationship between the D q 's. It was observed that fractal dimension might be used as a measure of signal complexity.

Music of brain and music on brain: a novel EEG sonification approach

“…Already, the art community has employed such chaotic patterns, and many examples exist of nonlinear/ fractal visual art created with the assistance of the computer (Pressing 1988;Truax 1990). Thus, non-linear dynamical modeling for source clearly indicates the relevance of non-deterministic/chaotic approaches in understanding the speech/music signals (Behrman 1999;Kumar and Mullick 1996;Sengupta et al 2001;Bigerelle and Iost Bigerelle and Iost 2000;Hsü and Hsü 1990;Sengupta et al 2005Sengupta et al , 2010. In this context fractal analysis of the signal which reveals the geometry embedded in signal assumes significance.…”