Modal analysis of impact sounds with ESPRIT in Gabor transforms
Authors: Sirdey A., Derrien O., Kronland-Martinet R., Aramaki M.
Publication Date: September 2011
Journal: Proceedings of the 14th International Conference on Digital Audio Effects (DAFx-11) (pp. 387-392, Paris, France, 19-23 September 2011)
Identifying the acoustical modes of a resonant object can be achieved by expanding a recorded impact sound in a sum of damped sinusoids. High-resolution methods, e.g. the ESPRIT algorithm, can be used, but the time-length of the signal often requires a sub-band decomposition. This ensures, thanks to sub-sampling, that the signal is analysed over a significant duration so that the damping coefficient of each mode is estimated properly, and that no frequency band is neglected. In this article, we show that the ESPRIT algorithm can be efficiently applied in a Gabor transform (similar to a sub-sampled short-time Fourier transform). The combined use of a time-frequency transform and a high-resolution analysis allows selective and sharp analysis over selected areas of the time-frequency plane. Finally, we show that this method produces high-quality re-synthesized impact sounds which are perceptually very close to the original sounds.
Successive synthesis using the n modes of highest energy: