Technology Mediated Soundwalking

When reviewing technology’s use within soundwalking, the most prevalent consumeravailable tool used within the practice is the handheld, battery-powered field recorder. Since its invention in the early 1930s, there has been a relationship between art and portable audio recording technology. This relationship is illustrated by Walter Ruttman’s Wochenende (1930), which is credited as the first radio production and the first artwork that utilised field recordings. While Ruttman’s system was cutting-edge then, it is large, expensive, and barely mobile by the standard of the mid-20th century just a few decades later. However, with the invention of the battery-powered field recorder in 1951, these devices quickly became vital tools for many avant-garde sound art practitioners and musique concr´ete composers who relied on field recorders to source sonic material from natural soundscapes and urban environments for their works. [124]

With the advent of lower-cost and more transportable models in the 1970s, the use of field recorders increased within sound-based artistic disciplines. In addition, field recording communities compiled vast online soundscape databases accessible by anyone with an internet connection. These projects include databases created by researchers and institutions such as the World Soundscape Project [33], Richard Benjamin Keys [125], Mari Laakso and Tiina Sarjakoski [126], the University of Utah [127], the British Library [128], and the Oakland Museum of California [129]. Databases such as these are significant as they provide a wealth of natural sonic material which artists and researchers can access for nearly any purpose. As it serves as the most common example of technology facilitation within the practice, the remainder of this discussion focuses on applications of field-recording technology while soundwalking.

This document refers to soundwalks that use electronic transducers such as microphones to mediate the listening experience as a technologically mediated soundwalk. Technologically mediated soundwalks are commonly executed for pedagogical purposes as a tool to encourage exploration of the in-situ sonic environment. In technologically mediated soundwalks, the participant does not record the soundscape but listens to the sonic environment in real time through the device’s microphone. The pedagogically focused soundwalks by Ian Rayes in the early 2010s provide typical examples of using this tool to generate novel listening perspectives. Each student is given a field recorder, a pair of headphones, and a microphone for the walks. They are guided by a facilitator and listen to the sonic environment through the field recorder’s microphone. Reyes describes these walks in his writing: "In this exercise, students experience listening as a microphone does, without intentionality or judgment, and with great sensitivity. The purpose is to introduce students to a critical listening technique allowing them to overcome their cultural conditioning, to become conscious of sound as such, and to recognize that one’s ears do more than receive sound, they actually produce it". [109]

Field recorders move the hearing apparatus outside the body and partly decouples the listener from their psychoacoustic processes. This removes possible soundscape colouration caused by the listener’s sensory apparatus while allowing them to focus their aural attention on specific sound sources. Through the use of unbiased microphone and amplifier technology, these soundwalks facilitate a comparatively objective listening experience where the field recorder’s microphone serves as an essential tool that acts as a training device to promote listening instead of operating as the artistic focus of the practice. These works encourage the use of microphones within hyper-soundwalks to support objective environmental listening experiences. Indeed, as pointed out by Rayes, the lack of “intention” and “judgement” provided by this technology is arguably what makes technologically mediated soundwalking so widely adopted.

Assembled by Bernard Krause in 2002, the definitive guide for ecologicallymotivated soundwalking is Wild Soundscapes in the National Parks: an Educational Program Guide to Listening and Recording. Commissioned by National Park Service in the United States of America, this 85-page-long document provides detailed instructions on how (and why) to conduct soundwalks within outdoor natural environments. In line with encouraging in-situ environmental listening, Krause argues that natural soundscapes are an under-recognised natural resource. To raise awareness of this resource, Krause proposes a set of seven programs, “which take the form of soundwalks, to help guide visitors on the path to discovery of good listening and field recording”. [6]

The observation that soundscapes are a habitually overlooked natural resource that should be actively conserved is not culturally unique to the United States. On all seven continents, numerous researchers have actively addressed this topic over the previous decade, including in Australia [130], Canada [101], Chile [131], China [132], Egypt [133], Greece [134], Israel [135], Italy [136], New Zealand [137], Poland [138], Qatar [139], Spain [140], Zimbabwe [141], and even the Antarctic [142]. While there are numerous technologically mediated soundwalks conducted for conservation efforts and as a pedagogical instrument, this discussion focuses on less-conventional technologically monitored soundwalk realisations to better inform our research objectives.

The founder of the Logos Foundation and a pioneer of mechatronic music, Godfried-Willem Raes, realised the “street happening” Klankspoor Sound-track in 1982. [143] The work was led by Raes using his purpose-built Soundtracker magnetic tape recording device. For this work, Raes and a group of artists travelled approximately 3 km across a city while recording environmental sounds. The recording speed of Raes’s Soundtracker varied throughout the installation as described by Raes in a typed handout for the project: "The tape is inserted into the recording-machine, while its utter end is fastened to the street... The machine is carried by one of the performers who follows the route and meanwhile provides to the recording with a microphone - held hand - at the speed of his own motion... This recorded soundtrack was... left behind as a track through the city. The tape was stuck on the street itself with markings of time and date, or, in parks and on soft soil, buried whenever possible".

Klankspoor and the Land art movement share characteristics, including a degree of physicality usually absent from the soundwalking practice. The process of physically embedding the magnetic tape in the ground near where the sounds were originally captured is reminiscent of the common Land art methodology of digging holes and putting things in them as demonstrated by works such as Bruce Nauman’s Untitled Piece, Jem Finer’s Score for a Hole in the Ground, and Jon Hassell’s Solid State (1974).

A contemporary example of artistically-motivated purpose-built soundwalking technology can be found with R´ebecca Kleinberger’s Phox Ears (2015). For the work, “a pair of head-mounted, independently articulated parabolic microphones allow the user to sharply direct their attention to distant sound sources, which are amplified and presented by built-in bone conduction transducer or optional external headphones”. Phox Ears demonstrates the use of conventional sensing technology (parabolic microphones) with unconventional actuation technology (bone conduction transducer) to augment the sensor capabilities of walkers to provide a unique technologically mediated listening experience based on the soundscape mixing approach to sonic installation art.

One common theme within technologically mediated soundwalks is the use of unconventional transducers to listen to environments that are typically not heard or beyond the natural biological capabilities of the human sensory apparatus. For example, Bernard Krause proposed using hydrophones for listening to marine environments in his soundwalking program guide. Alternatively, Christina Kubisch created numerous installations experienced as soundwalks that benefited from purpose-built electromagnetic induction technology that sonifies fluctuations in nearby magnetic fields. The first such work Il respiro del mare (1981), left) featured handheld cubes that participants move over wires to reveal placed sounds transmitted through electromagnetic waves emanating from the wires.

With a similar methodology as Il respiro del mare, but exhibited in an outdoor natural location, Kubisch’s Magnetischer Wald (1983) was exhibited in a forest where “cables (that matched the surroundings) were laid between trees and around the trunks”. In contrast to Kubisch’s earlier installations, where sounds are projected into the environment using loudspeakers fitted onto the handheld devices, Electrical Walks (2004 - present) fits the electronics into a pair of headphones. When beginning an Electrical Walk, participants are provided with headphones and a map highlighting particularly interesting electromagnetic emissions identified by Kubisch within a few blocks from the walk’s starting location. The maps provide suggested paths, but participants are free to determine their route and pace while exploring the city. Electrical Walks’s creative use of purposebuilt tools, along with its artistic focus on providing novel listening experiences through the use of purpose-built technology by revealing new perspectives on the installation location provide insight for how hyper-soundwalks can construct tools to augment existing sonic environment to support novel listening experiences and physical exploration.

The technologically mediated soundwalks introduced in this discussion use outdoor in-situ sonic environments as source material for their augmented listening experiences. The use of handheld field recorders, microphones, headphones, and microphone preamps is the most prevalent use of technology as a tool within soundwalking. This observation is especially true when discussing ecologically and pedagogically focused soundwalks such as those facilitated by Krause and Reyes. While these tools are well suited to address these walks’ artistic and research objectives, the reliance on general-purpose technology could be limiting when conceptualising artistically-motivated experimental soundwalks. To address this limitation, as demonstrated by the walks of Godfried-Willem Raes, Rebecca Kleinberger, and Christina Kubisch, some artistically-motivated soundwalk practitioners developed purpose-built tools to realise their artistic visions.

Most of the discussed works adopt an exhibition methodology that augments the soundwalker’s sensory apparatus. As technologically mediated soundwalking is the most prevalent approach to soundwalking with technology and serves as an essential reference when creating novel soundwalking experiences. While not the most prevalent approach, an alternate approach to leveraging technology within the practice of soundwalking involves using actuators to augment the in-situ environment with cochlear or visual stimulus. As this approach demonstrates broader applications of technology and a wide range of purpose-built solutions to soundwalks focused on facilitating novel listening experiences, these works are essential to our discussion.

Soundwalks Through Technology Augmented Locations

Where the soundwalks discussed above were conducted while carrying and using technology to mediate the listening experience, the works introduced in this discussion use technology to augment the installation venue according to environmental conditions. In 1967, the composer Alvin Lucier purchased several handheld echolocation devices called Sondols that are intended for use by “boat owners, acoustic engineers, and the blind”. After experimenting with the devices for a year, the performance Vespers (1968) was realised using soundwalking methodologies as an augmented listening experience conducted while physically moving through space. The work involved a group of blindfolded participants directed to “articulate the sound personality of the environment using the Sondols”. Vespers forced visitors to exclusively use their hearing to navigate through the removal of their visual awareness and expansion of their hearing apparatus. While Vespers does not directly promote listening to the in-situ sonic environment during the performance, the work highlights usually ignored acoustic properties of the installation space while requiring physical exploration. Given this exhibition methodology, Vespers is an excellent example of work using an innovative application of repurposed technology to facilitate soundwalking.

An important soundwalk that uses purpose-built technology which foreshadows a particularly active period of soundwalk research in the 21st century, is Iain Mott and Jim Sosnin’s Sound Mapping (1997). Sound Mapping is realised through four participants wheeling electronically augmented suitcases around an outdoor area to trigger samples of audio clips linked to specific locations. GPS technology tracks the suitcases, each containing a computer and speaker system. Like Vespers, Sound Mapping follows a mixing approach to cochlear augmentation where sounds produced by the artist are layered on top of the existing sonic environment. Participant movement triggers audio clips played from loudspeakers built into the mobile soundscape augmentation suitcases. Like with Vespers, as loudspeakers produce the soundscape augmentations, anyone at the installation venue can perceive the sounds, including visitors not operating the technology themselves. Therefore, this technological implementation provides a distinct accessibility advantage over approaches where augmentations can only be perceived by the soundwalking participants.

To contrast Sound Mapping’s approach, Sonic City (2003) by Lalya Gaye, Ramia Maz´e, and Lars Erik Holmquist is a soundwalk that benefited from wearable augmentation technology. Sonic City’s soundscape augmentation technology is used to “turn the city into a musical interface where data collected by the sensors controls the audio processing of live urban sounds collected by the microphone”. Sonic City is a unique example in this document due to its recognition of the user’s bodily conditions and modular application of a wide variety of sensors. The prototype discussed in, “prioritized robustness, portability, and modularity in technical decision-making”, and featured “a light-to-frequency converter, sound gate (microphone), metal detector, accelerometer, thermometer, and pollution sensor”.

Gaye’s team deployed a modular design methodology which allowed sensors to be dynamically added and removed in multiple locations on the jacket according to the needs of the walk. Gaye observed the benefits of this modular design methodology, “There was a good response to flexible sensor placement – for instance, the choice between locating the light sensor on a highly dynamic part of the body such as the hand or a more static location where it might remain shaded and ‘muted’ for extended periods”.

Gaye’s use of modular design principles and a wide range of electronic environmental sensors to generate augmented walking experiences gave the team flexibility to adjust the configuration of the installation’s hardware to account for unanticipated circumstances during exhibition. This kind of flexibly and adaptability is valuable for works which target environmental sounds and soundscapes as sonic environments are elusive, unpredictable, and mobile. Therefore, this modular approach to hardware design provides an essential reference for this document’s research projects and the establishment of the guidelines and requirements for thesis hardware.

Teri Rueb’s Core Sample (2007) is a GPS-facilitated soundwalk where “sounds corresponding to specific historic periods of the island are mapped onto its geographical elevation profile with sounds relating to periods further from the past at sea level, and sounds relating to more recent times mapped to the tops of the hills”. For this work, the walkers wear headphones which provide a range of samples ranging from environmental sounds to narration. As described by Frauke Behrendt, “each walk is a unique combination of the island’s soundscape at that moment and the Core Sample sounds on their headphones, co-created by the pace and locational pattern of walking”.

An analysis conducted by Behrendt of Core Sample and other similar mobile, locative media soundwalks observed this approach’s ability to direct attention to the in-situ sonic environment noting that, “walking and listening are not only key aspects of sonic interaction design for “placed sound”, they are also two powerful modes of connecting us to our surroundings – and show how mobile media can be part of this process of connection, rather than isolating or alienating us from them”.

In recent decades, the smartphone has been the most prevalent technology platform for soundwalking. Smartphones typically possess impressive computational power and a wide enough range of sensors, including a microphone, orientation sensor, temperature sensor, and light sensor. However, the smartphone feature that had the most impact on soundwalking is GPS. GPS sensing facilitates real-time location tracking with reasonable accuracy nearly anywhere in the world. This powerful technological affordance inspired numerous soundwalking practitioners to conceive of smartphone-facilitated soundwalking experiences. The most common technological strategy for smartphone soundwalking is based on creating digital apps that use geofencing technology to track the position of participants with GPS to trigger sound samples that correspond to locations in the installation venue.

Frauke Behrendt, a thoughtful soundwalk practitioner, academic, and artist, analysed numerous smartphone-facilitated soundwalks in her 2010 PhD thesis where she refers to the common technique of geolocated sounds triggered by the movement of walkers as “placed sounds”. In her writing, Behrendt brings attention to the agency these technologically-facilitated soundwalks give participants by allowing them to move through space at their own pace and experience the placed sounds in different orders. Behrendt refers to the agency participants enjoy in the sonic environment as remixing, the same term Kubisch used to describe interactions with her installations. Salient examples of smartphone-facilitated soundwalking include Mark Shepard’s Tactical Sound Garden [TSG] (2006), Andrea Williams’ Riverfront Park Soundwalk (2016), and Ellen Reid’s Soundwalk (2020).

While not artistically-motivated, the 2009 soundwalks of Gokce Kinayoglu use a soundwalking methodology that uses the mixing approach. Kinayoglu designed a system that tracked participant location and the direction they were looking while mixing external sounds. Participants wear headphones plugged into a backpack containing a laptop and other electronics and are instructed to explore an outdoor area to discover geolocated sounds. Results from Kinayoglu’s walks established that “sound can transform the emotion or mood associated with a place. In some cases, perception of sound can trick our other senses to induce synaesthetic effects”. Kinayoglu further observed: "The sounds were designed to be in overall harmony with the environment on the Esplanade yet it is clear that they highlighted certain aspects of the place and suppressed others. Sounds directed the participants’ attention, gaze and movements towards particular details, objects and locations. Certain features of the environment that would otherwise go unnoticed came into the attention of the participants while they were looking for the sources of the sounds".

Kinayoglu’s observations reveal the profound artistic potential of leveraging a mixed sounds approach to soundscape augmentation. While the soundwalks of Kinayoglu, Mott, and Sosnin are driven by the walker’s location within physical space, and Gaye’s walks sense a combination of environmental and biological conditions, these works do not directly respond to in-situ sonic conditions. This is not a shortcoming or disadvantage for these works, as their objectives did not require this feature. However, when targeting in-situ soundscapes as my hyper-soundwalk installations do, real-time environmental reactivity is a feature that can aid in directing attention to the sonic environment while hyper-soundwalking.

In contrast to the works already discussed, Musique Parabolique (2014) by Dennis Van Tilburg manipulates the in-situ sonic environment to produce real-time cochlear augmentations. Musique Parabolique is realised by Tilburg leading a group of participants through an outdoor location where sounds from the environment are sampled, looped, and mixed. Participants follow Tilburg while listening to the concert-like performance consisting of real-time soundscape mixing via a pair of wireless headphones.

Technologically, the work utilises a handheld parabolic microphone, a custom audio processing system, and a wireless transmission rig fitted into a modified handheld suitcase. Like many technologically-facilitated soundwalks, Musique Parabolique demonstrates environmental reactivity through the use of audio effects and manipulations to in-situ sounds before being heard by participants. This contrasts with the technologically mediated soundwalk Phox Ears, which utilised similar technology but did not manipulate audio collected from its microphones before conveying the sounds to the participant. A notable aspect of Musique Parabolique’s exhibition methodology that is similar to Raes’s Klankspoor, is the passive role of the participants who tap into the real-time performance managed by the soundwalk facilitator; Tilburg in the case of Musique Parabolique and Raes for Klankspoor. The works in this discussion were realised utilising transportable, self-powered, worn, carried, and rolled technology. This application of technology allowed the works to cover reasonably large geographical areas while granting participants high levels of freedom and mobility. The uses of technology introduced within this discussion facilitated novel listening experiences valuable for artistic and pedagogical purposes which would have been difficult or impossible to replicate otherwise.

Some smartphone and field-recorder soundwalks have confirmed the advantages of using technology to augment the participants’ perception of the environment to facilitate novel listening experiences. However, using smartphones and field recorders can limit the artistic possibilities of certain installation scenarios as these are general-purpose tools that are not optimised for soundwalking. While this limitation is usually not a problem for pedagogicallymotivated walks, it can inhibit the creation of artistically-motivated walks, which often desire a broader range of functionality to realise novel listening experiences.

References and Suggested Readings

This writing has been adapted from prior published works including my PhD thesis from Victoria University of Wellington. The reference numbers have been carired over from this document to ease my personal workload. I am planning on expanding this section to include more in-depth dicussions that are not restrained by the limitations imposed by writing a PhD thesis. Stay tuned for future writings! If you are interested in reading my PhD thesis where most of this writing originates, you can find it on this page HERE. Meanwhile, for easier reference, below are the in-text references (with links to many).

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