Vibroacoustic Analysis and Sound Synthesis of Percussion Musical Instruments

Overview

Percussion instruments, such as cymbals and drums, produce complex sounds with a rich frequency spectrum, which depend on numerous factors: geometry, thickness, material, striking method, and pre-strain (in membranes). Our research aims to decode this complexity through an integrated approach combining:

1. Computational Simulations:We develop FEM-BEM models (e.g., using LS-DYNA software) to study vibrational behavior and sound radiation. We conduct:
   • • • Modal Analysis:Calculation of eigenfrequencies and mode shapes.
       • FRF (Frequency Response Function) Analysis:Studying the instrument’s response to harmonic excitation.
       • Time Domain FEM-BEM Analysis:Simulating the temporal evolution of sound after an impact, incorporating real motion capture data.
2. Experimental Recording:
   • • • Electronic Speckle Pattern Interferometry (ESPI):We visualize vibration mode shapes with nanometer accuracy, confirming the accuracy of FEM simulations.
       • Motion Capture:We record the actual drumstick motion from professional drummers (at various dynamics, from piano to fortissimo) and use it as input for simulations, achieving realistic excitation modeling.
       • Impulse Response Measurements:We use an impact hammer and accelerometers to measure FRFs and calculate the damping ratio.
3. Sound Synthesis and Data Analysis: Our simulations allow us to calculate the sound pressure at any point in space and generate audio files (wav). We compare velocity spectrograms (on the instrument) with sound pressure spectrograms (in the air), revealing how structural vibration translates into audible sound.
4. Design Optimization: We parametrically investigate the effect of geometry (e.g., using arcs vs. lines to describe cymbal curvature), thickness, pre-strain, and materials (e.g., leather, Mylar, Kevlar, MS63, B8 alloys) on acoustic behaviour.

Our methodology lays the foundation for future physics-based sound synthesis and the creation of extensive sound databases for training machine learning models.

Publications

Brezas, S., Kaselouris, E., Orphanos, Y., Bakarezos, M., Papadogiannis, N.A., Dimitriou, V. (2025) On the Correlation of Cymbals’ Vibrational Behavior and Manufacturing Processes. Applied Sciences 15(3), 1425; https://doi.org/10.3390/app15031425

Brezas, S., Kaselouris, E., Orphanos, Y., Tatarakis, M., Bakarezos, M., Papadogiannis, N.A., Dimitriou, V. (2024). Vibrational Analysis of a Splash Cymbal by Experimental Measurements and Parametric CAD-FEM Simulations. Vibration, 7(1), 146-160. https://doi.org/10.3390/vibration7010008

Kaselouris, E., Paschalidou, S., Alexandraki, C., Dimitriou, V. (2023). FEM-BEM Vibroacoustic Simulations of Motion Driven Cymbal-Drumstick Interactions. Acoustics, 5(1), 165-176. https://doi.org/10.3390/acoustics5010010

Kaselouris, E., Alexandraki, C., Bakarezos, M., Tatarakis, M., Papadogiannis, N.A., Dimitriou, V. (2022). A detailed FEM Study on the Vibro-acoustic Behaviour of Crash and Splash Musical Cymbals. Int. J. Circuits Syst. Signal Process., 16, 948-955. https://doi.org/10.46300/9106.2022.16.116

Kaselouris, E., Alexandraki, C., Orphanos, Y., Bakarezos, M., Tatarakis, M., Papadogiannis, N.A., Dimitriou, V. (2021). Acoustic analysis of impact sound on vibrating circular membranes. INTER-NOISE 2021, Washington, DC, USA, 1-4 August 2021. https://doi.org/10.3397/IN-2021-2389