|A basic digital waveguide (likely of a string) with a rigid termination on one end (left) and a frequency-dependent attenuating filter at the other (right).|
Digital waveguide models are comprised of delay lines to represent the geometry of the waveguide, digital filters to represent the frequency-dependent losses and dispersion in the medium, and often include non-linear elements. Losses incurred throughout the medium are generally consolidated so that they can be calculated once at the termination of a delay line, rather than many times throughout.
Digital waveguide synthesis was developed by Julius O. Smith III and represent an extension of the Karplus-Strong algorithm. Stanford University owns the patent for digital waveguide synthesis and signed an agreement in 1989 to develop the technology with Yamaha.