Department of Architecture, Design, and Media Technology

PhD Defence by Silvin Willemsen

On Friday, October 1st 2021, Silvin Willemsen will defend his PhD titled "The Emulated Ensemble: Real-time Simulation of Musical Instruments using Finite-Difference Time-Domain Methods".

Last modified: 27.09.2021


09.00            Opening by the Moderator
09.05            Ph.D. defense by Silvin Willemsen
09.50            Break (coffee & tea will be served)
10.05            Questions and comments from the Committee. Questions from the audience at the Moderator’s discretion    (Moderator should be notified prior to the session)
12.00            (No later than) End of Session

After a short meeting the Committee announces its recommendation.

A reception will be arranged afterwards.

Assessment Committee

  • Associate professor Olga Timcenko (Chairman), Department of Architecture, Design and Media Technology, Aalborg University, Copenhagen Campus
  • Professor Julius O. Smith III, Center for Computer Research in Music and Acoustics, Stanford University, California, USA
  • Professor Augusto Sarti, Department of Electronics, Information and Biomedical Engineering, Politecnico of Milan, Italy


  • Professor Stefania Serafin, Department of Architecture, Design and Media Technology, Aalborg University, Copenhagen Campus. The supervisor is a committee member in a non-voting capacity.

A reception will be arranged afterwards. The PhD Dissertation as a download can be obtained from Silvin Willemsen by sending an email to him.


Department of Architecture, Design & Media Technology, Aalborg University, Copenhagen Campus.

Time and place

Friday, October 1st, 2021 - 09.00-12.00

Konferencesalen/ Conference room (1.001), A.C. Meyers Vænge 15, Building A, 2450 Copenhagen SV

The PhD Defense will be live-streamed here


Digital versions of musical instruments have been created for several decades, and for good reasons! They are more compact, more easy to maintain, and generally less difficult to play than their real-life counterparts.

One way to digitise an instrument is to record it and play back the samples, but this does not capture the entire range of expression of the real instrument. Simulating an instrument based on its physics, including its geometry and material properties, is much more flexible to player control.

An application of physical modelling, is to simulate instruments that are unplayable as they are too rare or vulnerable. A model of the underlying physics of the instrument could potentially resurrect the instrument making it available to the public again.

Furthermore, as a simulation is not restricted by the laws of physics, it could possibly go beyond what is physically possible. Properties such as the material or geometry of an instrument could be dynamically changed, which could potentially broaden the range of expression of the musician.

This PhD project has focused on the real-time implementation of several traditional instruments using finite-difference time-domain (FDTD) methods. The instruments include the well-known trombone, as well as more obscure instruments, such as the tromba marina and the hurdy gurdy.  Finally, a novel method has been created that paves the way for physically impossible manipulations of the instruments.