aMcGill University
bComputational acoustic modeling laboratory, CIRMMT, McGill University
Abstract :
In the context of preserving historical musical instruments as interactive digital acoustic
artifacts that can be played and heard in real time, we provide an overview of our recent
progress on measuring, modeling, and virtually recreating the sound radiation
characteristics of real acoustic violins. Our approach is based on measuring the
directivity of an acoustic violin and constructing an efficient digital filter model that can
be used for real-time processing of a whitened version of the electrical signal coming
from a silent violin as played by a musician. In a low reverberation chamber, we use a
microphone array to characterize the radiativity transfer function of a real violin by
exciting the bridge with an impact hammer and measuring the acoustic pressure at 4320
points on a sphere surrounding the instrument. From the real violin measurements, we
design a mutable state-space digital filter that allows to obtain the sound pressure
radiated in any direction. We characterize the silent violin transfer function by exciting
the bridge with an impact hammer and measuring the electrical signal at its output.
From the silent violin measurement, we design a recursive parallel filter that allows to
whiten the electrical signal and digitally recover the force signal.