Top page Yokoyama Lob. Home Page, Music analysis, Timbre of Instrument {

Target : Music and Information science, Numerical Simulation, Virtual Reality etc.

Who ? :
- I am professor and music composer of Meisei University(Homepagej
- I studied violin making at Tokyo and Cremona when I was young.
- I play cello and teach at small music school in Tokyo!
Brief biography, Papers and proceedings

Coupled numerical simulation of vibration and acousitc by numerical simulation
Mode vibration and acoustic radiation using COMSOL Multiphysics
3D model by micro CT scan and laser scanner.

Numerical simulation of the acoustic field around a violin of Stradivari (ICA 2022, pdf)
The vibrations and the sound field around the body of an old violin made by Stradivari are studied, in which this violin is scanned using a micro-CT scanner to generate a highly precise geometric image.

Coupled simulation of vibration and sound radiation in concert hall (WCCM 2022)
Coupled numerical simulations of the structure and acoustics of a violin body (JASA)
Mode vibration of violin plate (ICA 2019, pdf)



The numerical simulation of the mode vibrations of top/back plates of violin (Stradivari) and the radiation patterns around violin are performed by the finite element method using COMSOL Multiphysics.

Displacement of violin by forced oscillation on bridge where G string puts (196Hz). Sound pressure fields around body of violin in x-y plane 30 mm above from top of arch of top-plate. Sound pressure field in y-z plane in forced vibration by sine wave of 196Hz at the G string position on bridge.

Introduction Video https://youtu.be/Azo-UYfN4Hg
The mode vibration and eigenfrequency were simulated by Finite Element Methods in order to analyze the influence of the wood properties such as Youngfs modulus, thickness and density.

The numerical simulations of the mode vibrations of violin and the radiation patterns around violin https://youtu.be/5_6LMTzrM-Y
Guarneri Giuseppe Filius Andrea (1698)
Paper : Coupled numerical simulation of structure and acoustic of violin

Analysis of timbre by neural network (AI)
Identification of the timbre of violin by experiment and deep learning. Detection of violin by sound using the spectral envelope and MFCC.

Identification of violin timbre by neural network. 2022, PDF
Possibility of distinction of violin timbre by spectral envelope. 2020, PDF
Comparison of overtones Stradivari(1698), Fagnola(1923) and Pressenda(1838). Stradivari's S/N ratio is higher.
Relation between violin timbre and harmony overtone, ASA-JSA, 2016,PDF



Mechanism of bowing
Analysis of pressure and moment by the "bowing machine", which is 6]axis dynamic sensation sensor developed originally and can be controlled by easy programing.
Visualization of Vibrato Technique
Motion of vibrato of professional violinist taken by high speed camera and motion capture system. The corelation between expression words such as "Rich" or "Bright" and the overtones of violin sound is analyzed.

Wood and Rosin of Musical Instrument
Change in the acoustic or mechanical specific of wood by the heat-treatment and the medicine application.

Measurement Tools
Load measuring and bowing system(Original), FFT analyzer(Oros, NVGate),
High Speed Camera(Optronis), Motion Capture System(Optitrack),
LucchiMeter, Scanning Electron Microscope(SEM), moisture meter,,, etc

Society : Acoustical Society of Japan
Music and Computer of IPSJ
The Visualization Society of Japan
The Japan Society of Mechanical Engineers
Papers and proceedings

(c) M.Yokoyama