Transitional public spaces, like car parks and stairwells, often have unusual sound signatures designed to facilitate movement. Francesco Tacchini, Julinka Ebhardt and Will Yates-Johnson have created a project to explore this very phenomenon. Space Replay comprises a floating sphere that moves around its space and replays the sounds it picks up after a short delay.

The project was a side collaboration between two departments at the Royal College of Art. It was a response to a brief that asked how could sonic objects mediate between people, technology and places.

Tacchini and his collaborators wanted to look at the acoustic properties of transitional public spaces, such as lifts, stairs, tunnels and car parks. They defined two types of sound relevant to such space – ambient sounds that are natural or byproducts of localized activity (like traffic), and sounds that are intentionally designed and implemented, such as a lift arrival bell.

"To explore the relationship between how and where people experience these sounds we needed a tool – a digital or physical object – that could augment or disrupt that experience," Tacchini tells Gizmag. "A tool to manipulate sounds by either time delay, echo, live transposition or transmission, amplification or pitch."

Following a process of research, the team felt that the object would need to be visible and constantly present within the selected spaces. " I jokingly proposed that the it should float, started researching about lifting gas and levitation methods and made a working prototype, an air filled sphere attached to the ceiling," Tacchini explains.

After working on some prototypes, a finalized design was created. A battery-powered Arduino, an Adafruit Wave Shield and a small speaker were hacked together to record and playback audio on-the-fly. The components were vacuum-formed in a plastic cone so as to enhance the sounds produced and protect the balloon from the wires and PCB edges.

The final design weighed 120 g (4.2 oz) and the balloon was filled with enough helium to be able to rise up and hover. The whole project took about two weeks to complete.

The video below shows the sphere moving around a space.

Source: Royal College of Art