Building the carousel with its mechanics, electronics & loudspeakers

The whole carousel with its loudspeakers and electronics was developed  from scratch in Cologne. The carousel mechanics was designed and realized by the engineer Michael Reyl (Kunstmechanik).  The artist & sculptor David Fried helped to create the spherical arylic housing of the loudspeakers, which were finally produced in his studio in Düsseldorf.  The artist's basic idea for the electronics was to create a unit of sine generator, amplifier and illuminated loudspeaker which receives control data simply over a local network.  This electronics based on Arduino was finally realized by the engineer Gary Grutzek

  • Test setup in an industrial hall in Cologne, February 2014.
  • David Fried cutting the first translucent acrylic sphere for the loudspeakers.
  • Drilling holes in the spheres for the string mounts.
  • Gary Grutzek testing the electronics.
  • Last check of the spheres before lifting the carousel.
  • Michael Reyl explains the mechanics of the gear to the associate director of Hubble Space Telescope Antonella Nota (ESA/STScI).
  • First test hanging with four strings.
  • Replacing a loudspeaker.
  • The first revolutions of the fully assembled carousel in occasion of a private preview in Cologne.
  • The first test with a trailer crane in Cologne.
  • The control environment for the carousel programmed in Puredata (PD).


In principle each adressable loudspeaker can be controlled via the console sending a string simply via network (OSC/UDP). For the composition the artist programmed a sequencer like control software in Puredata (PD). Not only the loudspeakers can be controled but also the speed of the carousel. Additional sensor based velocity measurements allow to synchronize the rotation with the metrum of the composition.

In February a test installation was set up in an industrial hall in Cologne and first outdoor tests with a crane were performed. The preparations in Cologne are also documentated in the six minute feature Das Universum im Museum on the German daily science related boadcast nano on .

impression from the test setup in the industrial hall in Cologne (2:12 min.)

Special thanks for help and consultancy for the Cologne setup also to: Daniel T. Braun, Alexander Gurko, Jan Meulemann, Martin Nawrath, Tim Riecke, Ariane Riefert, Olaf Roggendorf, Patrik Roth, Johanna & Miriam Seidler, Wonbaek Shin, Dirk Specht. Thanks for improving the PD code to Janus Fouché.