Zeitraum

Zeitraum is a sound environment exposing the interrelation of time and space in acoustic communication and the implications thereof for music and sound art. The environment is composed of many identical sound sources distributed over a large space, playing an aleatoric ostinato of percussive sounds. When listened to from a particular location, 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 one particular (reference) location, compensating for the differences in propagation time. When walking away from that location, the regularity of the 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 reference location. By moving about, 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.

Zeitraum marks the end point in a series of case studies conducted in the course of the artistic research project The Choreography of Sound. ¹ The work was created to embody central research results and make them accessible through aesthetic experience. With Zeitraum, an aesthetic formulation of some of the basic constraints shaping the composition of spatial sound textures has been found, while touching upon fundamental conceptual and artistic conditions of possibility in electro-acoustic music composition and sound art.

Zeitraum exists in different formulations. ² Zeitraum Online was developed for the digital edition of PARSE journal. It is based on Zeitraum Göteborg, which was created for the courtyard of the Academy of Music and Drama in Göteborg as a contribution to the first biennial PARSE conference on Time in 2015. Zeitraum Online employs standardised web browser audio technology (the Web Audio API) to enable an interactive experience. It uses sound samples of the sound sources used in Zeitraum Göteborg (electromagnetically struck tubular bells), binaural rendering, convolution reverb, and a graphical interface to provide for an immersive spatial audio experience.

Users can move their listening position on a visual map of the courtyard to engage with the sound texture from any position. They may also turn their virtual heads in the environment, the sonic effect of which is best perceived via headphones. Besides the listening position, the reference position and the positions of the sound sources can be relocated. This enables the listener not only to explore but also to recompose the work. Hence an aesthetic experimental system is proposed allowing for testing ad hoc hypotheses about the work in a playful manner by reflection through experience.

The two central compositional choices of the work—the introduction of a reference position and the use of a random sequence with repetition control—are exposed by offering the possibility to neutralise them. Enabling or disabling the reference position and switching between a fixed and an aleatoric sequence allows a direct experience of the aesthetic consequences of the artistic choices. This kind of creative analytical access to the work is particular to the web browser formulations of Zeitraum (Online and Diagram) and distinguishes a reformulation from a documentation of a work. ³

To access the work go to:
Eckel, Gerhard. Zeitraum Göteborg. Video walkthrough with binaural audio. 2015. URL: http://vimeo.com/gerhardeckel/zeitraumgothenburg