This book addresses the acoustic signal analysis and spectral dynamics
of the tanpura, an Indian plucked string instrument. In addition, it
strives to provide a logical and objective explanation of Indian
classical musicians' cognitive experience. Issues of relevance in this
regard include the rich, mellifluous sound; the undulation of the
loudness; the somewhat cyclical variation of the timbre, which is
strongly related to these undulations; and the occasional perception of
virtual notes to which no strings are tuned.
The book analyses the materials used in the tanpura, the instrument's
simple structure, the intricacies of the lower bridge, and the theory of
string vibration with variable string length. Cognitive experiments to
provide the basis for perceptual quality assessment, as well as a
methodology for ranking, are described. This is followed by acoustic
analyses, both temporal and spectral, for sounds produced by male and
female tanpuras, for each individual string and the combined one. An
important aspect related to the naturalness of perceived sound, namely
the intrinsically associated random perturbations, is also discussed.
The apparent irregularities perceived in the acoustic signal produced by
the tanpura reveal the importance of examining the signal from the
perspective of non-linear analysis, an aspect that is also covered in
the book.
Given its scope, the book will appeal to students and researchers in the
fields of music acoustics, artificial intelligence, and cognitive
science, as well as musicians and musicologists around the world.
