Alpha Parameters

It is customary in the wave digital filter literature to define the alpha parameters as

where are the admittances of the wave digital element interfaces (or ``reference admittances,'' in WDF terminology). In terms of the alpha parameters, the force-wave parallel adaptor performs the following computations:

We see that multiplies and additions are required. However, by observing from Eq.(Q.17) that

we may implement , say, as in order to eliminate one multiply. In WDF terminology, port 1 is then a dependent port.

---

Order a Hardcopy of Physical Audio Signal Processing

Previous: General Parallel Adaptor for Force Waves
Next: Reflection Coefficient, Parallel Case

---

written by Julius Orion Smith III
Julius Smith's background is in electrical engineering (BS Rice 1975, PhD Stanford 1983). He is presently Professor of Music and Associate Professor (by courtesy) of Electrical Engineering at Stanford's Center for Computer Research in Music and Acoustics (CCRMA), teaching courses and pursuing research related to signal processing applied to music and audio systems. See http://ccrma.stanford.edu/~jos/ for details.