Intrigued by the phenomena and history of optical sound, Mariska de Groot makes  comprehensive analog light-to-sound instruments and installations. A new version of her Stirred Mandala performance arises from her ongoing research on optical sound and spiral movements in body and machine and is a result of Mariska’s residency at A4. The spinning pattern of a ‘tone wheel’ is projected on the floor, like a rug of light creating the instrument surface for the performer, while light-to-sound transducers become her playful tools.