+ WHO?
Andrea Cera
Collaborations:
UNIGE
CERTH
+ WHAT?
Examine the intrusiveness of urban soundscapes, explore innovative countermeasures, and analyse how soundscapes influence behaviour
+ HOW?
Modelling and automated analysis and enhancement of intrusive soundscapes
User testing
My ReSilence project starts from a curiosity : what makes certain sounds of our everyday soundscape more intrusive than others? What makes them salient, emerging? I’m not interested in our conscious evaluation of such sounds, but only in the primitive mechanisms that bring them to our consciousness. Can we use body movement as a privileged point of observation to learn something about these sounds? Intrusiveness in
city soundscapes can have implication of the health and quality of life of citizens, therefore this my research question has a potential to go beyond artistic implications.
I imagined a modular project in which sound design techniques, scientific experiments, artistic activities and pedagogical interventions are strictly intertwined, towards a contribution to tackling the problem of sound pollution and the creation of new solutions. The main focus of this research is to investigate dimensions beyond the simple pressure level, which is widely used to assess sound pollution. In particular, I focused on four timbral descriptors (spectral centroid, roughness, spectral sharpness and spectral skewness), and on temporal dimensions.
I based my work on a collection of intrusive urban sounds (traffic / roadwork noises) I recorded in several European cites and in several periods of my activity as a sound designer. I decided to focus on urban sounds because the scientific literature on sound pollution is largely based on this topic and, above all, because intrusive soundscapes can have serious implications on the health and quality of life of citizens. However, since I believe that intrusive sounds are unintended consequences of any kind of technology, I also added sounds like smartphone alerts and ringtones, music, etc., which can be intrusive at low pressure levels. The kind of technology I devised has the ambition to counteract any kind of sound which emerges in an intrusive way from a background.
Interactive Modules & Web Tools:
My ReSilence residency focused on two modules : ReSilent (Android app) and Moving Soundscapes (interactive installation) and on the participation in the design and implementation of a scientific experiment/pilot study of the InfoMus-Casa Paganini research centre.
ReSilent is a proof-of-concept smartphone app (Android only) in which I embedded a series of sound design techniques designed to lower the intrusiveness of sound signals. The sounds produced according to these sound design techniques were investigated and validated in the pilot experiment conducted with InfoMus-CasaPaganini. The ReSilent app applies in real-time these sound design techniques to the streaming captured by the smartphone’s microphone, and delivers the resulting counter-measures on the smartphone’s output, to be listened to with headphones. The core of these techniques lies in the creation of a sound background whose timbral make-up (in terms of spectral centroid, roughness, etc.) imitates the timbral features of emerging intrusive sounds – this new background, by virtue of its timbral resemblance to the intrusive sounds, lowers their salience, at the price of slightly increasing the overall level of the background. This (potentially negative) rise in overall sound pressure is counterbalanced by the filtering and dampening effect of the headphones.
The methods used to analyse the participants’ movements in the pilot experiment, and the sound design techniques aimed to lower sound intrusiveness were also at the core of the artistic installation “Moving Soundscapes”, in which the qualities of visitors’ movements are mapped to the intrusiveness of a generated soundscape and of a video stream. The installation consists of an interactive system which analyses in real-time the fuidity, jerkiness, predictability, and energy in the visitor’s movements, and maps these qualities towards timbral features of a soundscape generated by three main granulators and a series of additional synthesis modules. The video stream is based on images generated by a GAN network (see video).
Collaborations:
Pilot Experiment: The pilot experiment conducted with InfoMus-Casa Paganini allowed us to verify that sounds designed according to low-intrusiveness guidelines (and especially shaped along 6/10 sec. temporal scales) have a lesser impact on the qualities of human movement, compared with montages of intrusive urban sounds. The control condition, with only background noise (i.e. no foreground sounds) does not have an impact on the quality of movement. The focus on human movement gave us a direct, organic feedback, independent from user’s verbalisations, which often get distorted by personal, cultural, emotional factors.
ReSilent: The core algorithm was designed by me within the MaxMSP/RNBO environment, and then ported into and Android app by Julien Boit, using the JUCE framework.
Moving Soundscapes: The analysis of the visitor’s movement uses a series of concepts, methods and algorithms which derive by InfoMus-CasaPaganini background knowledge, in particular the modules on smoothness and jerkiness. Visual dimension: to help spatial positioning of the visitors, a video projection was designed, aimed at capturing their visual attention, and hence their position within the installation. The visual content was developed in collaboration with CERTH, which created a GAN network whose output is controlled by parameters connected with the 4 timbral descriptors mentioned above (spectral centroid, roughness, etc.), following a cross-modal mapping. In this way, visual features like brightness, saturation, presence of patterns, etc. corresponded to timbral features of the generated soundscape.
Impact: The knowledge gathered from the pilot experiment, the refining of sound design techniques, and the algorithms developed during the residency constitute a corpus of findings, ideas and solutions that could enrich the scientific research about sound intrusiveness, still today too much focused on the dimension of pressure level. The educational side of the residency (YouTube playlist dedicated to sound intrusiveness, workshops…) remains an important component to assure that in the future the discussion on sound pollution will recognise the importance of timbral saliency and temporal scales. Such pedagogical actions are important to ease the transition to this type of new technologies. For instance, given the unpredictability and variability of today’s soundscapes, the ReSilent app has two controls (sensitivity, level). Users need to learn how to use these controls to adapt the app’s output to a given situation, and this “tuning” needs a non-negligible listening skill, which can be easily developed with pedagogical interventions. The more knowledge a user has about the more or less degraded quality of a soundscape, the more the app will be helpful. However, the “tuning” question is also a dimension where the ReSilent app could be further developed in the future, in order to assist users in the process. In order to autonomously adapt the app’s output to changing external conditions, a series of presets could be developed, to be activated according to a mapping strategy connected with a trend analysis of intrusive events in the soundscape.
Moving Soundscapes: in December ’24 the installaton was presented in “Catastrof del Silenzio”, an experimental public event at the premise of the InfoMus-CasaPaganini research centre in Genova, which offered to the public an immersion in several dimension of this research project. Visitors were invited to a series of 8 workshops dedicated to the relation between intrusive sounds, movement, and urban environment. After the workshops they entered in the installation. The simple logic of interaction (any rigidity, jerkiness, lack of fuidity, unpredictability, strangeness perceived by the system generates an increasingly intrusive sound / image production), coupled with the experience of the workshop previously experienced, allowed visitors to explore their body, and to discover new dimensions in their movement and in the relation with the movement of other visitors.
ReSilent: The app was also introduced to the public in the “Catastrof del Silenzio” event at CasaPaganini, with a dedicated workshop. Furthermore, in June ’25 I presented it to an interested audience (neuroscientists, healthcare professionals, psychologists) in the frame of the symposium “The Sound of Longevity: Music and Technology for a Healthy Ageing”, organised by the European Interdisciplinary Council on Ageing, and I showed how it could be used to lower the intrusiveness of sounds in healthcare facilities (hospitals, ICU units, etc).
These presentatons go side by side with a presence on the Internet, through my YouTube channel, which will diffuse these activates even after the end of the ReSilence residency
Lessons learned: The most important point I take away from these experiences is about communication. Since we naturally tend to simplify questions by framing their components in separated categories, communication about low-intrusiveness sound design must always insist on the difference between progressively lowering the intrusiveness of sounds (the effect of this app) and eliminating it (which is impossible). The success of such technologies as ReSilent doesn’t sit on a clear, immediate effect, but on the cumulation of small improvements, not immediately perceivable, whose effect builds up with time and use. For the same reasons, an experience like interacting with Moving Soundscapes could be limited, without the immersion in pedagogical activities like the workshops we offered to the “Catastrof del Silenzio” visitors.
Our pilot experiment investigates the deeper ways in which intrusive sounds affect our life. It is not only a question of being annoyed or irritated by the sound of a passing car : the presence of an intrusive sound changes our body functioning, without our conscious realisation, and with little, if any, ability for us to control this effect.
The pedagogical actvites, especially the “Catastrof del Silenzio” event conducted with InfoMus-CasaPaganini, aimed at sensitising the public to the themes of Use Case n.3. The “Moving Soundscapes” installation offers a symbolic, abstract reading of such themes, and allows people who have been introduced to them to explore new ways of moving, of dealing with their bodies and the bodies of other visitors : this could have a profound effect in the general ways they interact with each other, and stimulate a refection on what does it mean to be “intrusive”.
Adaptability / interoperability:
The ReSilent app has a great potential of practical use, as a noise pollution counter-measure in the peri-personal space, anywhere the soundscape’s quality should be compromised. It doesn’t offer a clear-cut and definitive solution to the problem of noise pollution, but ReSilent users could become more tuned with the problem of intrusive sound, and become actors of a slow movement in which participants contribute to a world where the components of a soundscape are more and more in interaction, and less and less in mutually ignoring superpositions.
Talking about ReSilent at the symposium “The Sound of Longevity: Music and Technology for a Healthy Ageing”, organized by the European Interdisciplinary Council on Ageing.