Sound waves(The behavior of soundboards)

[Ron Nossaman]

http://www-ccrma.stanford.edu/~jos/waveguide/Dynamic_Terminations.html


Dynamic Terminations 

Perhaps the most glaring lack of realism in all plucked string simulations
described thus far is the
use of a perfect reflection at the ``bridge.'' A perfectly rigid bridge
cannot transmit any sound into
the body of the instrument, such as in a violin or guitar. 

The bridge of a violin can be modeled up to about  5 kHz, for purposes of
computing string loss, as
a single spring in parallel with a frequency-independent resistance
(``dashpot'') [61,62, page 27]. 

When a traveling wave reflects from the bridge of a real stringed
instrument, the bridge moves,
transmitting sound energy into the instrument body. How far the bridge
moves is determined by the
driving-point impedance of the bridge, denoted . The driving point
impedance is the ratio
of Laplace transform of the force on the bridge  to the velocity of motion
that results . 

etc.


Ron N