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2008, 17

Varsha Shah, Rekha S. Patil

Virtual piano using inharmonic dispersion tunable comb filter

language: English

received 25.08.2008, published 14.11.2008

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An excitation/filter system of inharmonic sound synthesis signal is presented with an application to piano, a stiff string instrument. Specific features of the piano string important in wave propagation, dispersion due to stiffness, frequency dependent losses, presence of phantom partials and thump noise are included in the proposed model. The modified narrow bandpass filter is used as a basic building block in modeling the vibrating structure. The parallel banks of narrow band pass filters known as Inharmonic Dispersion Tunable Comb filter is used to model the dispersion. The center frequencies of narrow bandpass filters can be tuned to follow the same relation as the partial frequencies of piano tone. Novel loss filter is designed to implement frequency dependent losses. The resulting model is simulated using MATLAB which works as a Virtual Piano.

Keywords: bandpass, bandstop, dispersion, inharmonicity, synthesis

7 pages, 7 figures

Сitation: Varsha Shah, Rekha S.Patil. Virtual piano using inharmonic dispersion tunable comb filter. Electronic Journal “Technical Acoustics”,, 2008, 17.


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Varsha Shah - M.E., Pursuing Ph.D. Working as Asst. Professor at Rizvi College of Engineering, University of Mumbai, India.

e-mail: varsha_shah_1(at)


Rekha S. Patil - M.E., Ph.D., Presently working as a Principal, D.Y.Patil College of Engineering, Talsande, Kolhapur, India. Has been in the teaching profession since last 35 years at Udergraduate and post graduate level. Has held various posts such as Head of the Department, Dean of academics, Principal. Has guided more than 40 students for M.E. dissertation. Currently 7 students are doing Ph.D. under her guidance. Has published more than 35 papers at national, international level conferences and journals.

e-mail: prekha46(at)