The Hexenkessel (witch’s cauldron) is an augmented musical instrument, combining a classical orchestral timpani with multitouch tracking technology and embedded video projection. Unlike traditional acoustic instruments, where sound production is inseparably linked to the physical construction, the Hexenkessel acts as a gestural interface for computer music, controlling live-electronics, sound synthesis and even stage-lighting, without affecting the original sound and functionality of the timpani. The initial prototype was realized in a tattered 21” timpani from the 1960s.

Hexenkessel prototype (2010)

After six month of tedious experiments with different systems for projection and mallet-tracking I succeeded in putting together a stage-proof setup that was publicly premiered with the composition Licht & Hiebe in 2010. In 2011 the Hexenkessel was shipped to the U.S. as submission to the Margaret Guthman New Instruments Competition in Atlanta. In this international competition for innovative musical instruments the Hexenkessel was awarded a honorary mention.

In 2014 the development was continued as part of the UMIS-Project after having rested for 2 years. Various components of the original prototype that appeared to be problematic in concert situations were able to be optimized. The main challenge was to reduce the time span necessary for setup and to permit the easy reproduction of the instrument and its parts. Also the software was entirely rewritten, thus enhancing the overall system-performance and simplifying the development of new graphical interfaces.

Hexenkessel v2 (inner view)

With the recent development of the Hexenkesselchen the technological basis was transferred into a standard 14” floor-tom. All features of the original instrument could be retained, while offering a portable, low-cost solution for every drummer.

Hexenkesselchen (2015)

Whether the Hexenkessel’s evolution will ever go beyond the status of a prototype, ready for small-scale production, remains to be seen. The target group of experimental timpani players appears too small to go into mass production. However, the Hexenkesselchen may appeal to a whole new group of potential users.

Meanwhile the use of the Hexenkessel in the context of contemporary music and multimedia performance arts goes on: See it in action at SMC 2016.

For more info see the papers on the topic.