In the content of the book publication:


TopoSonic Arts 1997-2006


Kehrer Verlag, Heidelberg 2007


Dr. Hanno Ehrler


To Render the Inaudible Audible…



Space-sound is a central term in the oeuvre created by the artist-couple <sabine schäfer // joachim krebs>. All pieces realized by the two composers deal with the behaviour of sound in space. Taken vice-versa, the term sound-space hints at other essential aspects of the composers' communal work. While composing, Sabine Schäfer and Joachim Krebs create sound-spaces in the twofold sense of the word. Thus, they look at the intrinsic, hidden realms of complex sound, while at the same time composing 3-dimensional acoustical figures establishing interactions with their surrounding space - be it a concert hall, a museum or even an open air area.



The 3-dimensional figures are sound worlds which may, by means of a network of loudspeakers, be positioned freely in space. Furthermore, the acoustical elements of a composition can be moved, more or less easily, through space. „Thus we create a sound-Body emitting music in different states of motion“, writes Sabine Schäfer. These „states“ depending on the location and mobilisation of a given sound constitute the essential elements of their works and are allotted very special meanings within the compository concept. Until the middle of the 1990s, Sabine Schäfer composed such pieces – that is, dynamical works carefully located in space – under the title „TopoPhonien“. However, since 1990, that is, since she started cooperating with the composer Joachim Krebs, the idea of space-sound emerges in a modified form. On the formal level, the exact positioning and location of sound elements in space is not assessed the same importance as before; rather, their work intends to fill a space with sound. The result is still a 3-dimensional experience, though less in the shape of a differentiated figure formed along the 3 vectors of space than as a work to be conceived in its entirety.




Furthermore, the artist-couple deals with „intrinsic sound-spaces“ which are externalized, thus making them experienceable. The necessary procedure developed by Joachim Krebs is based on digital audio technology that has existed since the 80s of the 20th century: the sampler and the computer. Joachim Krebs calls this procedure "audio microscopy" or „EndoSonoScopy“. In analogy to the process of optical microscopy, the sounds are magnified by the extension of time. As a reduction of velocity is coupled with a downwards transposition of pitch, elements of the sound which were up to this moment inaudible are rendered audible, for instance the frequencies of an insect's voice normally too high for human perception. Once they have been submitted to microscopy, the sounds shift into the sphere of human perception. Furthermore, rhythms and melodies will turn up which before were too fast to perceive.



The pieces composed on the basis of this material – Joachim Krebs calls them „Artificial soundscapes“ – follow the impetus to establish a sound art beyond traditional categories such as „autonomous work of art“, „sound collage“, „sound design“ or „ambient music“. Combined with the „TopoPhonien“ by Sabine Schäfer, they constitute the foundation for the overall project „TopoSonicArts“ developed by the artist-couple since 1998, comprising a body of more than 30 common Space-soundCompositions.



The project focuses on the sounds of nature, of animals and humans. These are recorded/sampled in the manner of musique concrète and thus made available for artistic elaboration. The selection of the composition material is already the first central aesthetical aspect of the artists' couple's project „TopoSonicArts“. On account of the evolutionary history of man and his biological integration in nature, this sound material touches on deep layers of our primal experiences and is understood quasi instinctively, in the sense that the sounds we hear bear connotations originating from our every-day, non-artistic living experience. Natural events carry an inherent reference to the extra-musical world; an insect or bird voice is immediately identified.



Thus, natural sounds such as they are understood by the artist-couple originate far beyond musical traditions so that they distinguish themselves fundamentally from the common „musical“ – instrumental or electronical – sounds produced by humans. They are untouched by the musical traditions or music-historical categories that affect all other sound material. Sabine Schäfer and Joachim Krebs claim that natural sounds possess a „universal character transcending all political and cultural limitations.“



In order to maintain this character in their artistic work, the two composers try to modify, and manipulate the natural sounds as little as possible, to let them speak for themselves. Thus, they call the technical process they apply on the material not "sound processing“ but resort to different terms: Sounds are „molecularized“ by temporal extension und downwards transposition. They are „fragmented“ by cutting out small pieces from the temporally extended sounds and composed in loops.; they are „elementarized“ by the reduction or intensification respectively of certain parameters, in some cases in order to eliminate disturbing features, in other cases to lend increased transparence to essential aspects of a sound. Analogous to optical processes, we may talk about magnification or focusing while foregoing any general modification of the initial material.



In the process, the intrinsic sound spaces opened up by microscopy, by „audio slow motion“ have the utmost importance. Any individual sound element has ist specific build-up time and its decay time as well as its very own reverberation which now appears magnified and intensified. It represents the ambient evoked by an insect or bird voice, the atmosphere intrinsic to that voice. It is these atmospheres as well as any other magnified and focused sound „shreds“ that constitute the elements of the actual composition process. They function as material building blocks combined and layered by Sabine Schäfer and Joachim Krebs to lend shape to the figures called „Space-soundMilieux“ by the composers.



The name „TopoSonicSpheres“ (title of a space-sound art project the artist-couple has been working at since 2004) contains the term of „sphere“ which in English comprises the meanings „field of activity“, „globe“ or „vaulted roof“. These semantic fields indicate the „reservation“ for listening the two artists wish to create with their Space-soundCompositions. Actually, it is the activity of listening which Sabine Schäfer and Joachim Krebs allocate utmost importance to. In their sonic art, they put major emphasis on sound while trying to push the (visual) arts aspect into the background. The optical and architectonical aspects of the spaces in which they realize their pieces serve, in the first place, for creating a space situation which enables undisturbed, concentrated and attentive listening.



In more recent times, the artist-couple designed so-called „audio-biospheres“, sound-spaces which the two composers call „living spaces for sounds“. These „audio-biospheres“ are artistic, musical products which may be considered, at the same time, as contributions to a sound ecology dealing with social and political problems of sound in the environment. Sabine Schäfer and Joachim Krebs put high emphasis on this aspect of their work – actually, it is reflected in sound itself. In their listening spaces, the two composers close out the outer world interspersed with noise and havoc. They display a sound material that distinguishes itself fundamentally from what is normally heard in man's everyday environment – cars, motors, machines, mobile pones, stereos. The listeners are confronted with the immediate experience that nature sounds are in short supply and a rare treat in our mechanized civilization.



The artist-couple aims at sensibilizing the listener for this endangered universe of sounds. Experiencing a Space-soundComposition by Sabine Schäfer and Joachim Krebs might contribute to the recipient's awareness of general ecological problems. As documented by the flood of political discussions in the media following in the wake of the climate report, these ecological problems always have a political aspect to them and in view of the ongoing destruction of our planet's biosphere by humanity, they do possess utmost explosiveness.



Hanno Ehrler, June 2007



© Hanno Ehrler

Translation Bettina Obrecht, 2007

Print, copy and further application of this text or parts of it only with explicit allowance of the author (

Dr. Hanno Ehrler studied musicology, art history and ethnology in Mainz. He is working as a freelance journalist a. o. for the Frankfurter Allgemeine Zeitung (FAZ) and the public German TV station ARD (subjects: contemporary music, science fiction, modern technologies).



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