Projects

Digital Variophon (supported by the DFG)

The Variophon is a wind synthesizer, that was developed at the Musicological Institute of the University of Cologne, Germany, in the 1970/80ies and at that time is based on a completely new synthesis principle: the pulse forming process. The central idea of that principle is, that every wind instrument sound can basically be put down to its excitation impulses, which independently of the fundamental always behave according to the same principles, and in which Karl Erich Schumann's Principles of Timbre are reflected (Schumann 1929, 15-18, 98 a. 100). In 1975 Jobst Fricke (1975, 407) and Wolfgang Voigt (1975, 51 a. 54) discovered the principles of generating wind instrument-like spectra with typical stable formant areas and spectral gaps evoked by the excitation pulses of double-reeds or lips. In a recent project, supported by the German Research Foundation (DFG), it is planned to digitally rebuild the Variophon in an improved version. The aim of the software-based modelling of that synthesis principle is both, creating a scientific experiment system for analyzing and synthesizing (wind) instrument sounds, as well as building a synthesizer, that would be an alternative to comparable Physical Modelling applications, because on the one hand this sound synthesis technique accounts for the place where the sound is generated, on the other hand just a single breath controller is required to produce all the sound-nuances, that are possible on a real instrument. A software-based Variophon makes it possible to bypass some restrictions, resulting from the limited technical feasibility at that time, as for example to synthesize the excitation impulses of original instruments by means of cosinusoidal or polygonal impulses, where the rising and falling edges of the impulses can be adjusted freely. Furthermore some important features of the sound production process, as the multiplicative interconnection between pulse forming and breath noise, can now be considered