Sound installation.
Streaming, 16 parabolic speakers, listening room, 24 speakers and electronics.
Exhibited at Oslo Central Station, October 2002.

Lydriket was the first work I did with public art. The work consisted of sixteen audio streams from around the country that was relocated into a sound installation at the Oslo Central Station. The idea of the sounds timbral and significant intrinsic value was central in the installation. The continuously variable structures and patterns in the sound sources combined with the different acoustic memories, perspectives and double exposures that occurred inside the Oslo Central Station constituted a fascinating web of acoustic information.

Right after the opening of the installation Erotogod in 2001 I moved to Berlin to work for half a year in the electronic music studio at TU1. While I still lived there I got an email from Notam2. Notam, NRK (the Norwegian public service broadcaster) and Rom for kunst3 had started a collaboration on sound art projects. Rom for kunst had access to the premises of the Oslo Central Station (Oslo S), and NRK had access to broadcast technology for streaming audio from all around the country. Would I be interested in making a work of sound art with this as a starting point?

The framework was interesting. 150,000 people travel through Oslo S every day, with all that implies, and through the streaming technology, I could exhibit sounds from vast geographical areas in real time. Besides, after working with the two synesthetic installations The Leap and Erotogod, I needed to work on a project where the sound’s intrinsic value was in focus.

I started working on the concept and presented a sketch. The sketch showed a listening space with 24 loudspeakers mounted inside the walls. Hanging from the ceiling on the outside of the room there was a row of loudspeakers facing towards the room’s centre. Inside the room a specially designed sound system made it possible to extend not only beyond the geographical place but also inwards into the sound. I eventually put together a team of sound artists, consisting of myself, Trond Lossius and Risto Holopainen, and work was started.

In the original draft the listening room was located in the centre of the Oslo Central Station, with rows of speakers drawing listeners from all over the station. For security reasons, the listening room was moved in the finished installation to the side of the main entrance. Illustration: Asbjørn Blokkum Flø.

High resolution listening experience
The installation opened in the autumn of 2002 at Oslo S. The facade was covered with a spectrogram showing the timbral qualities of the sound and a sound wave that showed the temporal qualities. Inside the station, different areas on the floor were highlighted, and when inside these areas you could hear audio streams superimposed with the sound of the station. These sound fields led towards the installation’s custom built listening space where a sound interface made it possible to examine the different audio streams timbral qualities, and to project these onto the immersive and three-dimensional listening sphere formed by the speakers that were hidden in the walls, floor and ceiling of the listening room.

However, the installation’s real starting point was out in the field, with microphones placed throughout the country. These audio streams were sent to Oslo S and played back on rows of speakers with parabolic reflectors hanging from the ceiling. The speakers were hung at a height that made the focal area around the listener’s ear, and thus increased the focus of the sound fields, while limiting unwanted sound leakage into the station. The ceiling loudspeakers pointed towards the installation’s listening space. This room was built with high acoustic precision, and the room’s sound interface, combined with the 24 speakers hidden behind the perforated walls made the high resolution listening experience possible.

Although the speaker system in the installation Erotogod (2001) constituted a very effective sound sphere there were no speakers placed in the most critical listening position, the listener’s ear level. In Lydriket this was therefore extended with eight speakers placed at ear level. This system had 24 speakers combined with a custom designed acoustic room, and made it possible to create a highly credible three-dimensional sound.

Sounds timbral and intrinsic meaning
Central to Lydriket was the idea of the sound’s timbral and significant intrinsic value. The artistic process had already started through choosing the different audio streams. Aspects such as the sound’s structural possibilities, its ability to change over time and semantic ambiguity were central. Along with the speakers at Oslo S the audio streams formed a web of acoustic information. In the installation the audio streams mixed with the train stations own acoustic identity, and thus created new, imaginary spaces. This dislocation examined the relationship between different acoustic memories and viewpoints, and between the visual and the auditory. In the central listening room, a gradual acoustic and visual isolation arose, and the focus shifted from the contextual and over to the acoustic and timbral qualities of the sound. Here, the listener could take direct control of the sound and process the acoustic information himself.

Complete natural listening events
So, the starting point for the installation was a web of audio streams from microphones placed around the country. This was supposed to be sixteen parallel audio streams4 which was sent in real time to Oslo S, but for technical reasons, a last-minute change reduced this to four audio streams in real time and twelve recordings of the remaining audio streams played back from an audio player.

The sixteen audio streams listed along the coast from north to south, were: the coast at Berlevåg, the Sami Parliament (Karasjok), beer bottling plant at the Mack brewery in Tromsø, low tides on the Helgeland coast, football match with Rosenborg at Lerkendal stadium in Trondheim, the Ålesund pier, barn at Hornnes in Førde, casting at Outokompo Norzink in Odda, Fiskepiren in Stavanger, marina in Kristiansand, sheet workshop at Hydro Porsgrunn, Sandefjord Torp airport, railway transition in Drammen, the National Theatre subway station in Oslo, the river Mesna in Lillehammer, the glass cabin in the old town in Fredrikstad. Illustration: Asbjørn Blokkum Flø.

The artistic work began with the selection of the audio sources. To ensure a diverse catalogue of sounds I asked the sixteen local NRK branches to collect sounds in the three categories natural sounds, industrial sounds and urban sounds. Based on this catalogue we started the investigations of the audio stream’s artistic and musical potential.

Some sounds had a timeless quality such as the continuous sound of the waves crushing against the coast of Finnmark, while other sounding environments had only been around for a few years. Several of the sound sources had acoustic features that represented a specific meaning for that area. This could include the sounds of nature, sports, agriculture, transport and industry. While the sound of a marina was an acoustic feature for the seafaring town of Kristiansand, the sound from the zinc plant had a similar function in the industrial town of Odda. Both these acoustic features told something important about the site’s identity.

These found objects were in themselves complete, natural sound events with timbral structures and patterns. This applied to natural sounds as well as urban sounds. They were all living sources of acoustic information, and had at any given time an unheard sounding complexity. Through the installation, we uncovered that meaningful sonorous structures and patterns existed as a natural process in all sounds. All that was required was mindful listening.

This listening was fundamental in the artistic and musical work of the installation. The listening act was fundamentally focused towards compositional structures, both in the choice of audio streams, in the processing of them and ultimately in the public’s listening. The listening act was expanded geographically through the web of audio streams. At the same time, through the microphones, we could focus the listening inwards towards the smallest constituents of the sound. Since the audio sources initially contained all the necessary information, the work of the installation became a sort of composition in reverse. The structures and the patterns were already there in the form of a hidden music, and through listening we could unveil and juxtapose the various layers of sound to discover the unheard.

The audio streams were in themselves complete sonorous universes, and they were not static. On the contrary, they were of an evolving nature, where changes took place along several parallel time-scales. The sound changed not only in the moment, but also on a slower time-scale. It could be a tidal change in the seaside, the change during the working day at the factory, or recurrent loudspeaker announcements at airports and train stations. These shifts in the installation’s musical material moved between the different acoustic polarities of the audio streams, creating a vibrant sound space in constant change.

The installation’s starting point was these audio streams, but in everyday life we often filter out this kind of environmental sound. In a visually oriented culture our basic response to the world is semantic; we are looking for meaning. Similarly, we want to make sound significant. Sound is seen as meaningful when it is part of a semantic context in which meaningful symbols and codes are established, as in traditional music or in language. When we filter out the environmental sounds it becomes irrelevant, it is moved to the background and becomes noise. However, these environmental sounds were not without significance: they were semantically ambiguous, and in the installation’s redefinition of the acoustic context, we wanted to transform the ambiguous noise to be a potential carrier of meaning.

Web of acoustic information
The semantic potential of the sound was therefore only apparent when we redefined the acoustic setting. To achieve this, we constructed a web of acoustic information. The combination of microphones, which were located around the country, and the speakers located inside the urban setting of the train station, formed a web of audio information that held artistic and compositional qualities.

The microphones captured the separate sources of information, and sent them as audio streams to the installation where they were reconstructed into a new unity. Here we connected several spatial points together at a defined point in space, and in this way the installation amounted to a three-dimensional tracing of the Norwegian acoustic topography. In this composed web, the acoustic horizon expanded. The simultaneous listening points sent acoustic data that were recreated as artistic and timbral information.

When I presented this idea to co-composer and sound artist Risto Holopainen he commented dryly that this sounded more like a gigantic surveillance system than an art project. And it is true that there were many similarities between Lydriket and the systems for surveillance and intelligence. From SOSUS5 to Echelon6, from Watergate to the modern-day accumulation of digital traces, the handling of audio data has always provided valuable information. Just as the gathering of signals in intelligence aims to uncover hidden relationships, we wanted to uncover hidden relationships in the timbral and significant intrinsic value of the sound in Lydriket.

The timbral and significant intrinsic value is enhanced when the sound is pulled out of its environment and placed into a new frame of reference. In Lydriket this new environment was Oslo S, a place that for many Norwegians are known for drugs, prostitution and crime. The clock tower in the square outside the main entrance was once characterized by a Norwegian author as “a giant thermometer stuck in the capital’s rectum.” But Oslo S has many identities. Every day, endless streams of travellers go through the station with their own luggage and their own memories. Similarly, the station carries on its own acoustic luggage and memories. The place has served as a railway station for over 150 years, and gradually the acoustic impression has been transformed from horse cabs and steam locomotives to escalators and loudspeaker announcements. As it emerges today, Oslo S is a fascinating piece of sound design in which the different layers of background music from shops and messages from the public address system are superimposed with the sound of people constantly passing through.

It was in this acoustic environment that the installation operated. Lydriket existed in the tension between the live audio streams, and the live acoustic environment of the station. The audio streams were played back over loudspeakers hanging from the ceiling, and this sound was superimposed with the station’s actual environmental sound setting. In the original sketch the listening room of the installation was to be located in the centre of the train station and rows of speakers, in the same architectural design as the listening room, were to stretch out as acoustic tentacles into the station in order to draw the listener into the installation’s centre. For practical reasons, these speakers had to be replaced with simpler speakers in plexiglass.

The environmental sounds that were streamed into these ceiling loudspeakers created a transparent acoustic cover, and the continuous variable combination of different audio streams and the station’s acoustic identity created a compositional and spatial form. Not only was the sound environment at Oslo S shaped by the sounds that poured into the station, but the audio streams themselves also changed their character in light of the new context. In traditional listening situations such as concert halls, in front of the stereo, or with portable music players, this natural interaction does not exist, and the goal is on the contrary to isolate the listening as much as possible from external and disturbing sounds. In Lydriket, this interaction between the intended and unintended sound was central.

The transfer of audio streams from around the country to Oslo S held a significant aesthetic value. The sounds were not isolated from the environment. They came from an initial setting and were placed into a new one. The dislocation was surprising. Audio streams from beaches, harbours, agriculture and industry placed inside Oslo S appeared as an acoustic contradiction. The purpose of this dislocation, however, was not to display a national romantic idealized version of an exotic Norway, but a radical transformation of the acoustic meaning of this public urban space.

Through the displacement we filled Oslo S with new acoustic memories. The station’s 150 years of acoustic history was superimposed with a wide range of sounds. These sounds contained their own meaning. Audio streams of water, sea, fishing, agriculture, industry, transportation and sports said something about identity. The sounds evoked the visitors’ own acoustic memories, which were well documented in the installation’s guestbook. The sounds triggered memories of childhood and identity, historical and personal events, and for many visitors the sounds worked as an immediate and emotional time portal.

The acoustic memories also had a three-dimensional quality. The audio streams originally belonged to specific locations, and were three-dimensional acoustic imprints that bore on the spatial information of these sites. They were volumes in space, and depicted the sound’s original occupation of their own space. This spatial quality was enhanced through displacement, and in its final, invisible form the interaction between the audio streams and the sound of the station assumed a three-dimensional character. The scale of the sound was also displaced through this dislocation. The installation’s acoustic environment was opened up by the large dimensions of, for example, the sound of the ocean, only in the next second to be reduced by the sound from the train station’s own speaker system. Further interferences of the dimensions came with acoustic double exposures, where the station’s announcements of train departures were superimposed with similar announcements from the airport’s audio stream. The size of the space was no longer a constant, and in this way the sound material obtained a new range of possible acoustic meanings.

Although the installation consisted of three-dimensional sound objects, there were obviously no corresponding optical objects in the installation. In Lydriket the correspondence between the visual and the auditory was turned upside down. It was as if the sound travelled faster than the speed of light, and we could hear further than we could see. The distances collapsed while the visual remained unseen. Listening has a different form of spatial correspondence than visual perception. Sound is immersive and at any moment we hear overlapping fragments of acoustic energy. It is not necessarily any direct correspondence between what we hear and what we see, we can hear something both before and after we see it. In the installation this relationship was further displaced. Not only were the audio sources invisible and geographically scattered, they were also superimposed on top of each other, as well as with the sound of the station. This new spatial dimension represented the installation’s own room.

Such an exhibition of invisible rooms might itself seem contradictory, but sound displayed in the public space in this way caused an additional tension between what you heard and what you saw. If you took the time to listen, new visual aspects appeared. The listener’s own imagination and fantasy were the mental spaces where their own images were created, and this was the installation’s visual space. As you listened, the mental visual space interacted with the station’s space and together they created a third room consisting of ticket gates, factories, convenience stores, farms, timetables, beaches and travellers in a continuous stream of sound.

Into the sound
Located in the centre of this double-exposed public sound space was a physical room inside the room, the installation’s focal point; the listening room. In the installation’s outer room the sound from the station blended with the audio streams, and the listener’s inner space mixed with the station’s external visual space. But in the listening room, it was different. The physical distance from the listening room to the microphones placed around the country was great, but the psychological distance to the outside world was perhaps just as great. Inside the room one were isolated both visually and acoustically.

Lytterommet, installasjonens midtpunkt, lå i sentrum av Oslo S. Foto: Jøran Rudi.The listening room, the installation’s focal point, was located at the centre of Oslo S. Photo: Jøran Rudi.Lytterommet, installasjonens midtpunkt, lå i sentrum av Oslo S. Foto: Jøran Rudi.

The acoustic isolation from the installation’s outer space to the inner listening space took place gradually. When you entered the listening room you heard less and less of the railway stations environmental sound until it completely disappeared in the room’s centre. In here, you only heard the audio streams and their processed versions. But the room was visually isolated as well, and all the technology that produced the sound was hidden behind the installation’s walls. Similarly, just as Pythagoras gave lectures to his disciples behind a veil, we heard the listening room’s sound come from invisible sources behind the wall. This acousmatic7 listening prevented visual and mental distraction, and increased the focus on the sounds intrinsic acoustic and timbral qualities. Listening in the centre of the room, one became taken by the immersive and sensual qualities of the sound.

The focused experience in the listening room was a natural consequence of the room’s acoustic design. The room was based on my original sketches, architect Morten Kaels developed these further to a finished concept and acoustician Bjørn Strand did the acoustic design. The room was specifically designed for acoustic balance and colour. Materials and dimensions for the absorbents were carefully chosen, and the room’s dimensions were optimized for timbral balance. Reflective diffusers was also placed to regulate the room resonance, and the entrance to the listening room was designed to limit sound leakage in and out of the room.

Early sketch of the listening room. Illustration: Asbjørn Blokkum Flø.
The listening room’s focused experience was a consequence of the acoustic design. Illustration: Morten Kaels.

This optimal listening situation created a unique, detailed listening, and one became moved by the complexity of the sounding material. Through the listening room’s 24 speakers placed in a sphere that surrounded the listener, dynamic and intense dislocation of the audio streams could be realized. Stripped of all external visual reference, the attention shifted inwards into the sound.

Processing of information
In the centre of the listening room there was the sound controller. With this, the listener could process the information through his own choices. In here, the listener himself constructed the acoustic reality. This was not an unambiguous interaction, but rather open to interpretations and understandings, different meanings and layers of consciousness. Here the users attributed their own references and intentions directly to the sound. The audio streams were always the same, but the changing character of the sound, combined with the listener’s individual choice, continued to produce unique results. The results were always related but never the same.

The sound controllers were organized into three parts. The lower part was a spiral with push buttons to select which audio stream to listen to. Unlike the audio streams outside in the station area, these audio streams were heavily processed. Each single stream was transformed into a musical gestalt. Here, we continued the work from the previous two installations The Leap and Erotogod, and the idea of different forms of microsounds where the sound was split into small grains was central. The combination of the precise acoustics and the immersive loudspeaker sphere gave good opportunities for three-dimensional sound, and considerable effort was put into the design of the different movement-patterns and three-dimensional qualities of the sound.

Early sketch of the sound controller. Illustration: Asbjørn Blokkum Flø.
Final version of the sound controller. Illustration: Morten Kaels.

There were two rows of switches above the spiral, one for rhythmical and timbral manipulation and one for spatial change. Adding different durational patterns on top of the patterns that were already there made the rhythmical changes. In this way, you got three layers of time information; the audio streams own time, the musical gestalt’s time and the time of the durational pattern on top of this. The timbral changes entered the sound’s spectrum and changed them in the same way. Just as with the time information the spectral changes added new layers of information on top of the foregoing. The last series of switches provided spatial changes. The musical gestalt initially contained spatial information and spatial patterns, but by using this last row with switches one could ‘freeze’ the room, enlarge or reduce it, make it move further away or come loser, or simply intensify the existing movement patterns.

The controller was organized in three parts, a spiral with push buttons that chose the audio stream and two rows of switches, one for rhythmical and timbral manipulation and one for spatial change. Photo: Asbjørn Blokkum Flø.

It was a conscious choice to make the interaction this straightforward. Previous experience had shown us that a high density of information in the interface is not necessarily an advantage in interactive systems, and that an immediate feedback in the sound gave the user an immediate and understandable response to their actions.

Critical counterpoint
On top of the interactive layer of sound there was a second layer. This sound was constantly changing, but outside the control of the user’s interaction. The various pieces forming this layer were based on early recordings of the audio streams, and were composed by Risto Holopainen. The section served as a counterpoint and a comment to the listening room’s interactive audio streams. As the compositional process progressed Risto also incorporated sources that would appear as external. This could be national-romantic clichés such as mooing of cows, sheep bells and roaring crowds, or it could be remnants of old sounds that NRK had forgotten to remove from the tapes we received, such as voice tests and old radio programs. These “foreign elements” slid right into Risto’s characteristic sense of surreal and paradoxical combination of sounds, and commented on the other parts of the installation in a critical but humorous way.

Radio and Web
Lydriket existed in two more forms, on the Internet and as radio. In the Internet version, the sounds from the listening room were streamed together with images from the listening room’s exterior. In this way, the sound that poured into the installation was now sent back out in to the country where it came from. The third manifestation of the installation was in the shape of a radiophonic composition. This was a 25-minute composed sound piece made on the basis of the installation’s material. The big challenge here was to transform a work operating in nonlinear time to a work based on linear time, with a beginning and an ending. The radio version became Norway’s contribution to Ars Acustica8 in 2003 and was broadcast in 20 countries.

Random travel through Oslo S
The original title of the installation was Norge – et lydrike (Norway – a country of sound), later abbreviated to Lydriket (a country of sound). The title had a double meaning. On the one hand, it described a country consisting of sound, and on the other hand, it played on the concept of “Lydrike” (puppet state), ie Norway’s centuries-long period subject to Denmark. This period is considered to have been strongly identity-forming, and in the installation we wanted to investigate whether identity could also be traced in sound.

The central focus was the sound’s timbral and significant intrinsic value. On the one hand, we created a listening space that was so acoustically and visually controlled that the focus naturally went inwards into the sounds timbral aspects. On the other hand, we investigated the sound’s significant aspects through displacement and superimposition of audio streams in a public sound space. The railway station’s public space also made sure that we had an audience of several thousand people who stopped under the speakers every day, and just under five thousand9 who visited the inner listening room during the exhibition period of eleven days, which must be regarded as a large number of visitors for an experimental sound art installation. Furthermore, the location at Oslo S gave us the additional possibility to communicate far beyond the concert hall and the gallery’s narrow circles. The installation was both technically and conceptually challenging, but the overwhelming positive response from an audience with very different backgrounds randomly travelling through Oslo S made the sometimes intense working process worth it.

Lydriket was shown at the Oslo Central Station during the Ultima Festival 2002.


  1. TU: Technische Universität Berlin. Kommunikationswissenschaft, Elektronische Studio.
  2. Notam: Norwegian Center for Technology in music and the arts.
  3. Rom for kunst (Room for art): a privately run art project working with art at Oslo S among other things.
  4. The sixteen audio streams listed along the coast from north to south, were: the coast at Berlevåg, the Sami Parliament (Karasjok), beer bottling plant at the Mack brewery in Tromsø, low tides on the Helgeland coast, football match with Rosenborg at Lerkendal stadium in Trondheim, the Ålesund pier, barn at Hornnes in Førde, casting at Outokompo Norzink in Odda, Fiskepiren in Stavanger, marina in Kristiansand, sheet workshop at Hydro Porsgrunn, Sandefjord Torp airport, railway transition in Drammen, the National Theatre subway station in Oslo, the river Mesna in Lillehammer, the glass cabin in the old town in Fredrikstad.
  5. SOSUS stands for Sound Surveillance System, and is a series of underwater listening posts that were created during the Cold War to monitor Soviet submarines.
  6. Echelon was created during the Cold War and is a controversial network that collects and analyzes information on a gigantic scale. The system is operated on behalf of Australia, Canada, New Zealand, UK and USA.
  7. Acousmatic: The word originates from the outer circle of Pythagoras’ disciples called Akousmatikoi which Pythagoras taught hidden behind a veil. The term was taken up again in the mid 50’s by the Musique Concrète movement, and can in its simplest form be described as sound in which the sound source is hidden.
  8. Ars Acustica is a group within the European Broadcasting Union (EBU) that promotes, initiates and coordinates activities regarding radio art and sonic art. It is also the name of an annual competition that among other things includes sound art for radio.
  9. The number of visitors was 4793, and was counted manually by the installation’s guards.

Asbjørn Blokkum Flø: concept, music, sound, sound programming
Trond Lossius: music, sound, sound programming
Risto Holopainen: music, sound

Morten Kaels: architect
Bjørn Strand: acoustics

Bjarne Kvinsland: producer
Tilman Hartenstein: producer
Alf Magnus Reistad: producer
Henrik Sundt: electronics
Anders Beckmann: carpenter
Kåre Sponberg: lighting
Odd Frydenberg: lighting
Jan Neste: design
Arnfinn Christensen: design

Produced by Notam, NRK, Ultima and Rom for Kunst ved Oslo S / Mesén.

More about Lydriket:
Rudi, Jøran 2003. Norge – et Lydrike, Norway Remixed: a sound installation.
Johnson, Geir 2002. The Night Train to Oslo.

Video editing: Asbjørn Blokkum Flø

Photo: Jøran Rudi
Map: Asbjørn Blokkum Flø