Real-time Physical Modelling

The interaction between musicians and their instruments is a key aspect of expressive music performance. Therefore, recent studies have focused on understanding how the actions of the players affect sound generation. Based on experimental results obtained using both human performers and an artificial blowing machine, we present a numerical model that, taking the players’ actions into account, may synthesise expressive woodwind instrument sounds. Implemented in C++ the model allows real-time performance on a standard desktop computer, thus enabling the user to modify the model parameters in a live performance scenario. Apart from varying parameters related to the embouchure of the player and the length of the resonator (i.e. mimicking modifications that could take place in real playing) this model also allows virtual modifications that would not be possible to realize in the physical world, such as a cone gradually morphing into a cylinder and vice versa. Besides parameters related to the excitation mechanism and the geometry of the instrument, the user is able to modify the properties of the air inside the instrument and the magnitude of the viscothermal losses. Further modelling and implementation details, as well as a demo video can be found below.

Features:

  • Variation of reed parameters (stiffness & equilibrium position)
  • Variation of player control parameters (blowing pressure & tongue position)
  • Variation of instrument geometry (lenght & end radius) and air-column properties (speed of sound, losses, air density)
  • Dynamic grid allocation
  • Numerical stability
  • Real-time performance

References

  • V. Chatziioannou, A. Hofmann and S. Schmutzhard. A real-time physical model to simulate player control in woodwind instruments. in Proc. International Symposium on Musical Acoustics, 2019. https://pub.dega-akustik.de/ISMA2019/data/articles/000034.pdf
  • V. Chatziioannou, S. Schmutzhard, M. Pàmies-Vilà and A. Hofmann. Investigating Clarinet Articulation Using a Physical Model and an Artificial Blowing Machine. Acta Acustica united with Acustica 105 (4), 682-694, 2019. https://doi.org/10.3813/AAA.919348