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arXiv · 0809.1320

The eigenspectra of Indian musical drums

G. Sathej·R. Adhikari
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Abstract

In a family of drums used in the Indian subcontinent, the circular drum head is made of material of non-uniform density. Remarkably, and in contrast to a circular membrane of uniform density, the low eigenmodes of the non-uniform membrane are harmonic. In this work we model the drum head by a non-uniform membrane whose density varies smoothly between two prescribed values. Using a Fourier-Chebyshev spectral collocation method we obtain the eigenmodes and eigenvalues of the drum head. For a suitable choice of parameters, which we find by optimising a cost function, the eigenspectra obtained from our model are in excellent agreement with experimental values. Our model and the numerical method should find application in numerical sound synthesis.

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G. Sathej, R. Adhikari. 2008-09-08. The eigenspectra of Indian musical drums. https://doi.org/10.1121/1.3058632

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