Zeitraum (German for ‘timespan’, literally ‘time space’) is a sound environment exposing the interrelation of time and space in acoustic communication. The environment is composed of many identical sound sources dispersed irregularly in a large space, playing an aleatoric ostinato of percussive sounds. When listened to from a particular location (the sweet spot, marked with a spot light on the floor), the pattern is perceived as an accented but isochronous beat. The ostinato is structured such that the sounds from all sources arrive with the same delay at the sweet spot, compensating for the differences in propagation time. When walking away from the sweet spot, the regular pulse gets more and more distorted as the distances to all sound sources change and with them the propagation delays from the sources to the listener. What starts as almost imperceptible deviations and passes through various areas with different kinds of grooves, ends up in a rhythmically completely disrupted and apparently chaotic sequence of events when listened to from far off the sweet spot. By moving about the space, the audience explores a space literally made out of time, a time space – a bewildering experience enacted through one’s locomotion, revealing the always baffling relativity of observation.