ListenTree: Audio-Haptic Display in the Natural Environment

Abstract

In this paper, we present ListenTree, an audio-haptic display embedded in the natural environment. A visitor to our installation notices a faint sound appearing to emerge from a tree, and might feel a slight vibration under their feet as they approach. By resting their head against the tree, they are able to hear sound through bone conduction. To create this effect, an audio exciter transducer is weatherproofed and attached to the tree trunk underground, transforming the tree into a living speaker that channels audio through its branches. Any source of sound can be played through the tree, including live audio or pre-recorded tracks. For example, we used the ListenTree to display live streaming sound from an outdoor ecological monitoring sensor network, bringing an urban audience into contact with a faraway wetland. Our intervention is motivated by a need for forms of display that fade into the background, inviting attention rather than requiring it. ListenTree points to a future where digital information might become a seamless part of the physical world.