Computer modeling of musical instruments has been an active area of research for nearly two decades. Because of inherent nonlinearities in such systems, time-domain models have been of particular interest. Most time-domain modeling techniques for complete woodwind instrument systems involve the convolution of a pre-calculated or measured instrument reflection function with a nonlinear driving mechanism . Digital waveguide (DW) modeling  is a technique which simulates traveling-wave propagation along the length of a woodwind instrument bore using digital delay lines. Thus, a distributed model of the air column is used to continuously calculate the instrument reflection function, which allows variation of the resonator parameters in a physical manner during a simulation.
Most previously reported models of a woodwind tonehole have characterized only one state of the hole (open or closed). A dynamic DW tonehole model was presented , but this neglected the effects of closed holes.