Digital Waveguides

A digital waveguide is a sampled traveling-wave simulation for waves in ideal strings or acoustic tubes.
A (lossless) digital waveguide is defined as a bidirectional delay line at some wave impedance .

$\begin{figure}\centerline{\scalebox{1}{% \input{waveguide.pstex_t}}} \end{figure}$
As before, each delay line contains a sampled acoustic traveling wave. However, since we now have a bidirectional delay line, we have two traveling waves, one to the ``left'' and one to the ``right''.
While a single delay line can model an acoustic plane wave, a digital waveguide can model any one-dimensional linear acoustic system such as a violin string or a clarinet bore.
In real acoustic strings and bores, the 1D waveguides exhibit some loss and dispersion so some filtering will be needed in the waveguide to obtain an accurate physical model of such systems.

``Music 206: Digital Waveguides'' by Tamara Smyth, Department of Music, University of California, San Diego (UCSD).