Movement and sound
It was long known from the Gestaltists that two identical visual targets moving across each other can be perceived either to bounce off or to stream through each other . In 1997 Sekuler et al. demonstrated that a brief sound at the moment the targets coincide biases perception toward bouncing.
Both artists have a keen interest in synchronised sound‚ but our approaches are from either end of the digital/analogue spectrum. Because the medium deals with embodied perception of movement‚ we felt it was essential that the artworks incorporated sound.
This is how we recorded Carol’s voice for the audio of the Swing and Bounce experiment.
When we came to create the Gestalt Circle‚ the sound emerged almost intuitively. This was partly due to time constraints‚ but also was an example of the artist’s accord on using synchronised sound. The audio was much remarked on by participants who viewed the piece and organically highlights the difference between phi and beta movement by using digitally synchronised sound to the former and vocal analogue sound for the latter.
This is the first attempt to record the sound effects for the Gestalt circle….
…but there was too much background noise‚ so Bruno ended up recording the sounds in his house until 5 in the morning‚ the night before the opening! He used audio samples of spanish castanets to create the clicky sound of the Phi movement‚ and blew in the microphone in the same way that Carol did for the ‘airy’ sounds of the Beta movement.
It was an interest in synchronous sound that first brought Carol and Bruno together to work on the project. A major reason for enjoying the experience of viewing the Diasynchronoscope comes from the medium’s unique ability in combining animations with precisely synchronized sound. Sound is treated as a formal raw material that is morphologically equivalent to the iconic objects placed and lit in the Diasynchronoscope. This means that sound and visuals are intertwined in a way far beyond that of most screen-based media and this makes for a unique and comforting gestalt experience. This synthesis of sound and vision is a primary element of much of animation’s appeal‚ and was investigated at length by Michel Chion who coined the term for it of ‘Synchresis’‚ defining it as: The forging of an immediate and necessary relationship between something one sees and something one hears. 
In the Diasynchronoscope we are constantly challenging ourselves to create ‘bonds of inevitability’ between audio and visuals so that we create an added dimensionality to the way artworks are perceived.
 Metzger W (1934) Beobachtungen über phänomenale Identität. Psychologische Forschung 19:1–60
 Sekuler R‚ Sekuler AB‚ R Lau (1997) Sound alters visual motion perception. Nature 385:308
 Chion‚ M.: Audio-Vision : Sound on Screen. (trans. Gorbman‚ C.) Columbia University Press‚ New York 1994