Four recommendations inspired by sustainable HCI
In this paper, we propose a set of reflections to actively incorporate environmental sustainability instances in the practice of circuit bending. This proposal combines circuit bending-related concepts with literature from the domain of sustainable Human-Computer Interaction (HCI). We commence by presenting an overview of the critical discourse within the New Interfaces for Musical Expression (NIME) community, and of circuit bending itself—exposing the linkages this practice has with themes directly related to this research, such as environmental sustainability and philosophy. Afterwards, we look at how the topic of environmental sustainability has been discussed, concerning circuit bending, within the NIME literature. We conclude by developing a list of recommendations for a sustainable circuit bending practice.
NIME, environmental sustainability, circuit bending, template
•Applied computing → Arts and Humanities → Performing arts; Sound and music computing
Circuit bending is an evolving practice. First formalised by Reed Ghazala, it has evolved through time in parallel with new technological discoveries. Even today, circuit bending is still gaining interest within the musical context and the NIME debate: by bending circuits and pieces of technology, many fresh Digital Musical Instruments (DMIs) can be designed and created.
Circuit bending offers some implicit environmentally-friendly approaches. For example, it tends to be directly bonded to the reuse and repurpose, as a whole or in part, of discarded Electric and Electronic Devices (EEDs), which acquire a new meaning and purpose through the bending process. However, to the best of our knowledge, a comprehensive discourse on the environmental potential of circuit bending is still missing. While this concerns circuit bending as a whole, if considering only its practical side the focus usually tends not to be on its linkage with environmental sustainability.
In this paper, we propose a set of reflections and recommendations to actively and consciously incorporate environmental sustainability instances when practising circuit bending. Our objective is to provide guidance on what could be improved or avoided to consolidate an environmentally aware circuit bending practice. By building upon the critical discourse that has been developed within the NIME debate in the last years, we developed these recommendations by combining literature from 1) the circuit bending practice, 2) its cultural and philosophical frame, and 3) sustainable HCI.
A long tradition of (self-)reflective research has characterised the NIME debate and, recently, it has increasingly focused on ethical (and environmental) issues related to music technology. For instance, researchers have reflected upon the value of community in interactive music research , creative and technical discourses surrounding the design of DMIs , general research approaches —with the specific aspects also being investigated such as evaluation strategies  or thematic analysis , the identity of NIMEs , the use of scores , the meaning of gestures , and inclusivity in gender diversity .
In the last edition of the conference, Fasciani and Goode presented an extensive overview of the evolution of the conference itself. In this paper, the authors estimated the carbon footprint of the various editions of the conference, based on the travel distances of attendees . The recent critical and ethical reflections that have been incorporated increasingly within the NIME conference can be also observed in the diversity1, ethics2, and—particularly relevant for this paper—environmental3 statements and codes. Overall, environmental sustainability has been recognised as an important ethical value (see also ). Additionally, papers critically reflecting upon the conference started to be presented at the event. For instance, Hayes and Marquez-Borbon addressed the market demands of the neoliberal university . Bin discussed the importance of documenting for promoting critical discourse , arguing in favour of ongoing, flexible and open documentation which can «[…] show us how our work is responding (or failing to respond) to social issues such as environmental concerns.» . Morreale et al. have argued for the need for an outward-looking effort towards looking at social, ethical, and cultural issues related to the NIME discourse . In their paper, the authors also touch on environmental issues: «[…] environmental costs are not limited to the production and disposal phase, and our analysis should also include environmental costs at run time […]» . To conclude, a recent paper specifically focused on a more sustainable NIME practice . In this work, the authors highlight a general lack of research focused on environmental sustainability within the NIME discourse and propose eco.nime.org4, a wiki that aims to promote a more environmentally aware practice. Additionally, they proposed a model to reflect on the environmental impact of NIMEs. Particularly relevant for this paper is the attention reserved to hidden environmental costs caused, for example, by Storage, or Travel, and the attention to Disposal.
Circuit bending is a cross-disciplinary practice, blending a broad range of studies; it is difficult, therefore, to present a clear definition. On the one hand, a core set of disciplines are related to the practical and technical aspects of circuit bending encompassing electronics, IT, physics and design. On the other hand, other areas of knowledge—such as philosophy, ethics, and sustainability—contribute to its contextualization in the contemporary world and society from a different, humanistic perspective. Circuit bending has been adopted primarily in music  and performative sonic art , where artists investigate sonic results obtained through the modification of circuits. Circuit bending primarily focuses on exploring unexpected behaviours of circuits by applying modifications to their electronics. By modifying the actual electrical schematic, electricity flows differently, leading to outputs different from the originally designed ones.
Fernandez and Iazzetta clearly stated that circuit bending is deeply related to the Do-It-Yourself (DIY) culture . Such movement is primarily composed of nonprofessional enthusiasts of a given sector (i.e. hobbyists) keen on modifying, repairing, or improving objects related to their field of interest. It should be noted that the adjective ‘nonprofessional’ does not refer to the skills and expertise owned by the practitioners—who tend to be at least informed hobbyists. Instead, it refers to the fact that the activities undertaken within the DIY scope are not driven—at least not directly—by commercial purposes .
It is common to find, in place of ‘circuit bending’, the lemma ‘hardware hacking’ used almost as a synonym. However, Collins has suggested that each have two slightly different meanings. While the former is completely based on extreme experimentation, the latter needs to be an informed practice, at least partially. The author also points out that this does not diminish the ‘bending’ practice. Indeed, he adds that «[…] Bending’s try-anything extreme experimentalism can produce wonderful results never anticipated by the original designers of the device being bent.» . Overall, it seems that the difference between the two lemmas is considered trivial . Additionally, these two terms are used interchangeably both in literature and informal resources . This relation to the hacking practice connects circuit bending to an open attitude. Indeed, the hacking culture is historically and culturally at the basis of the Free/Libre and Open Source Software (FLOSS) . As discussed later on in a further section, FLOSS tend to have a multifaceted positive impact on environmental sustainability.
From an environmental sustainability standpoint, circuit bending has been associated with the concepts of recycling, reusing, and repurposing . Thus, it can be seen as a practice that opposes current market policies and (planned) obsolescence . Indeed, technologies and devices used in the bending processes do not need to be new. Rather, they can be recovered amongst the many EEDs that—often while still usable and in good conditions—are discarded every day, turned into e-waste that feeds the growing pile of hazardous scraps . Hertz and Parikka acknowledged the chance for discarded EEDs to be ‘resurrected’ and repurposed to new uses through circuit bending . To summarise the path of a discarded EED—from being useful for a specific task to becoming e-waste, and back again to a repurposed device through circuit bending—the authors have also proposed the concept of ‘zombie media’:
«Yet, dead media creeps back as dangerous toxins into the soil, or alternatively as zombie media recycled into new assemblies. […] Zombie media is concerned with media that is not only out of use, but resurrected to new uses, contexts and adaptations.» .
Ghazala also underlined the ecological and environmental values undergoing the circuit bending practice. Indeed, he described discarded or abandoned-and-forgotten EEDs piling up in garages, second-hand or flea shops, and garbage bins as the primary sources of material for circuit benders . It is absolutely undisputed that, as Goddard argues, repurposing disposed of EEDs as bent objects, is not at all a way to solve the persistently growing problem of e-waste disposal . On the contrary, it could potentially worsen this issue as bending a circuit could easily lead to irreparable damages, resulting in a burnt circuit, void of any further usefulness. The value of circuit bending in relation to environmental issues, therefore, does not exclusively lie in its practical side (repurposing discarded devices) but requires conceptual and theoretical reflections and awareness. Simultaneously, through technical-creative practice, circuit bending can foster reflections and create or enhance connections amongst different perspectives on sustainability. In doing so, it unveils issues and criticalities related to current production and market policies, capitalism, consumer society, and social inequities—to name a few.
Circuit bending has the potential to be an ecologically and environmentally sustainable practice. However, when it comes to the practical side, this potential is not always uncovered nor sufficiently highlighted or extensively investigated. Reed Ghazala  and Nicolas Collins  wrote the two most complete manuals for circuit bending. These books propose the fundamentals of circuit bending and relevant theory through several practical projects . However, they do not address the environmental potential of circuit bending. Only the former author, building upon what he has previously stated , acknowledges that discarded circuits can be very useful in the practice—like gem mines for circuit benders . Besides that, informal resources (e.g. virtual courses on e-learning platforms5 and YouTube channels6) tend to encourage buying cheap electronic devices in second-hand shops for the sake of saving money. However, whatever the source or typology of the devices is, bending them when still functioning and usable might not be an environmentally aware practice—and this is particularly true when the bender is a beginner or when the bending process is still in an exploratory phase. Indeed in such cases, burning circuits and components is not uncommon.
Circuit bending’s «[…] potential for enhancing relationships between the psychological, social and ecological aspects of sustainability […] are considerable when it is seen as a possible precursor of future and diverse ways of bending» . This statement by Cagol et al. apparently suggests that the bending process is going to bend more than just a few recovered circuits. We can stretch this consideration to the point that our (pre-)conceptions are going to be bent. Through de-contextualisation and re-contextualisation, a discarded EED can be turned into a crafted new piece of musical technology. What was a useless device is transformed through the bending process, thus acquiring a different value.
Neo-materialist philosophy proposes a framework to better address this shift in our perception, which can help to reconsider the objects (EEDs, in this context) we label as useless or expendable. This change of perspective is realised by projecting human qualities to these objects, placing them on a more equal footing with us and thus contrasting humans’ tendency to think of ourselves as separate from the system in which we live. Such an approach leads to addressing disposal from a different standpoint: «With such a view, the conception of casually discarding an often fully-functional piece of machinery for an improved one can take on an aspect similar to that of disposing of an old friend.» . In his practice, Ghazala embraces this way of thinking by considering objects not too different from living beings. Besides referring to bent instruments as ‘alien instruments’ or ‘living instruments’, he forges the term ‘BEAsape’, standing for ‘BioElectroacousticAudiosapian’ . This term has been used to describe some of the first instruments he built, which needed both circuitry and body contact .
However, like every living being, bent instruments have their lifecycle. The bender-musician is responsible for that as they have to choose whether to turn it on—playing it but consuming its life faster—or conserving it by not using and maintaining it in a ‘sleeping’ state . The choice becomes more difficult as bent circuits do not age linearly, but tend to run faster towards their burnout due to the modifications. The same characteristics identifying them as special, one-of-a-kind instruments, are also their curse, and a balance does have to be found between use and conservation: «The instrument grows a little older, moves a little closer to early demise, every time it is turned on. Don’t play it to save it? Play it to let it sing?» . Following this way of thinking, critical listening as an ecological activity  can help to monitor the consumption of the electrical components, and thus the ‘health status’ of the bent instrument over time—as, due to its livingness, it changes its voice as it ages .
Circuit bending implicitly embodies glitch  and post-digital aesthetics . While both focus on errors and artefacts the latter is engaged, in particular, with digital hardware and software as its name suggests. Although ‘digital’ may not seem a central adjective concerning circuit bending—which mainly employs analogue hardware—, Andrews proposed a description of the post-digital composer that perfectly fits the profile of the circuit bender: «[…] the post-digital composer sets processes in motion to arrive at the unforeseen, and make aesthetic use of what would normally be regarded as deficiencies and errors in digital process.» . The ‘deficiencies and errors’ described are of particular interest in the context of circuit bending if read from a broader perspective. Indeed, they could refer not only to the unpredictable and sometimes chaotic sounds generated by bent instruments but also to the hardware itself which—treated as a useless scrap and discarded—is recovered and repurposed for a new, artistic aim. The same mindset can be applied to the linkage between circuit bending and the glitch aesthetic. Of course, the most prominent connection concerns the sounds. But bent instruments themselves can be described as ‘glitches’ within the hardware domain—unexpected ‘reincarnations’ of devices originally designed for other purposes . The simple technological and practical bending process—the material repurposing of an old, discarded device—has, indeed, a great aesthetical meaning too. This approach to the ‘reincarnation’ of technology through glitch exploration is deeply related to environmental sustainability. Both post-digital and glitch aesthetics focus on retrieving artistic meaning through (already) faulty or discarded pieces of technology rather than on destroying or bending, for this purpose, functioning devices bought for little money in a shop.
To understand how the circuit bending discourse has been articulated in relation to environmental sustainability within the NIME context, we relied on the official open repository Zenodo7 and performed a systematic search using ‘circuit bending’ as the keyword (query performed in October 2021). According to the manual of Zenodo , by default, the system returns papers that match the keyword in any field of the repository. Although this method is fairly basic, it is robust enough to present a broad overview of the papers that self refer to circuit bending. The research produced 16 results, of which five articles directly address circuit bending, while the others simply used one of the two words in other contexts. These five articles are: , , , , . Here we discuss them in comparison with other literature, in light of the scope of this paper.
Overall, the possibility offered by circuit bending to physically work on the instrument by changing its parameters through cables, switches, and potentiometers has been particularly appreciated as it allows for an experience full of immediacy and exploratory value . As a downside, bent instruments, which were not originally designed for performative purposes, offer limited and simpler interactions compared to digital or proper physical instruments ; such limitations of a piece of technology could, however, become artistic possibilities . Finally, the aforementioned immediacy and the characteristic unpredictability allow them to ‘evolve’ their perceived status—from the products of a semi-improvised hardware hacking practice to essential parts of a highly explored artistic form with plenty of opportunities .
Hardware hacking provides a useful perspective concerning the openness of musical devices . Drawing from the scope of engineering, it rejects the ‘black box’ approach in favour of a 'white box’ one . White box, which allows users to access every component of a given device, is a distinctive central trait of circuit bending . Openness does not only make the action-sound relationship more tangible and clear but also encourages the process of appropriation of the new instrument by the player . Through this, limitations (constraints) of the bent instruments can be explored and turned into novel artistic features . This approach is also strongly connected to media archaeology—as it allows one to better understand bent instruments/NIMEs by taking into account the history and evolution of the media upon which they are built . However, it also exposes that a musical instrument is not considered as merely for its physical properties, rather for its cultural context and boundaries .
However, there is generally a lack of exposure of information regarding the connection between circuit bending and ecology—that is, the possibility to repurpose and reuse discarded devices through this practice. Marasco et al. theoretically and collaterally acknowledge an aesthetical linkage occurring between the upcycling movement and the hacked devices when performing with the latter . Only Rieger et al., although not referring specifically to the technical side of circuit bending, take into account and expand its core upcycling idea when describing their NIME ‘Driftwood’. Constructed, as the name suggests, with repurposed wood it aims to shed light on the forgotten nature and origin of objects that are often underestimated, encouraging their reuse. «It is easy to forget the importance of trees when they are merely driftwood, kindling or paper.» , and the same logic can be applied to discarded circuits and devices. A last relevant example that offers a reflection from a different perspective is ‘Fragile Instruments’ by Haddad et al., which have been designed with an external shell meant to be broken . Built to be played through (creative) destruction, they recall the practice of destroying musical instruments during a live show, which, common in some musical contexts, can have a bold political and artistic meaning . It is important to highlight that the authors of the ‘Fragile Instruments’ designed them to allow for the construction of the external shell by employing salvaged and recyclable materials . Despite this attention, the generation of waste implicitly at each reiteration of the performances is not widely discussed.
The overall lack of specific interest in the environmental sustainability of circuit bending within the NIME debate is not surprising. In fact, in a recent systematic literature review performed by Masu et al., it emerged how this theme has been scarcely scrutinised in this context so far . Therefore, in the following section, drawing from the debate around environmental sustainability and HCI, we wMill propose a set of recommendations aiming to turn circuit bending from a solely artistic practice to an environmentally aware one.
Some valuable reflections about environmental sustainability and technology have been developed within the HCI debate (e.g. ). For instance, Blevis pointed out «[…] the perspective that sustainability can and should be a central focus of interaction design […]» .
Mankoff and colleagues  proposed a distinction between sustainability in and through design. This distinction has been widely used in successive literature (see for instance ). Sustainability in design occurs when the environmental issues are addressed during the material design of an artefact. Sustainability through design, on the contrary, refers to those artefacts that address environmental issues indirectly, thus promoting the awakening of environmentally-friendly practices. This second approach focuses on «[...] ways of living and processes of social change.» .
Blevis has discussed ten actions, ranging from greatest to the least negative environmental impact—from disposal to active repair. Based on these, the author suggested ten principles to promote a sustainable HCI practice: 1) Disposal—when the design causes the disposal of physical or digital material; 2) Salvage—when the design saves previously discarded physical material; 3) Recycling—recycled materials are used or the design facilitates future recycling; 4) Remanufacturing for reuse—when the design provides for the renewal of material for reuse or updated uses; 5) Reuse as is—when the design provides for the transfer of ownership; 6) Achieving longevity of use—when the design allows for long term use of the materials; 7) Sharing for maximal use—when the design allows for use by many people; 8) Achieving heirloom status—when the design supports long-lived appeal that motivates preservation; 9) Finding wholesome alternatives to use—when the design eliminates the need for the use of physical resources; 10) Active repair of misuse—when the design aims at repairing the harmful effects of unsustainable use .
Finally, recently it has been pointed out that the FLOSS can facilitate generative upcycling8 or simply prolong the lifespan of hardware . Indeed, being open can prevent planned obsolescence and foster social collaborations to develop updates that can extend the lifespan of technological artefacts.
As shown, Mankoff and colleagues proposed two main approaches to address sustainability in interaction design: in and through design . We support that circuit bending offers a valuable perspective over both of them. On the one side, it promotes the practical reuse and upcycling of technologies and circuits ; on the other side, its aesthetic values and approach are based on re-contextualisation (use of such technologies) . Thus, it can be used to promote recycling and reuse as a message of the final bent instrument. Additionally, we have also seen how circuit bending is connected to hardware hacking  and can support rejecting the ‘black box’ approach in favour of openness , and how that can expand the lifespan of hardware . In addition, openness in hardware and software, when well documented, has the potential to contribute to promoting critical reflection .
All these aspects shape notable standpoints to promote environmental sustainability in and through design, as summarised in the following table.
Circuit bending characteristic
Type of sustainability
Use of discarded EEDs
It reduces the environmental costs of raw materials and prolongs the life of the technology
Aesthetic values and approaches are based on re-contextualisation
It can promote recontextualisation and reuse as an artistic message of the final bent instrument
Rejecting the ‘black box’ approach in favour of openness
Can prevent obsolescence and foster social collaborations to develop updates
Has the potential to contribute to promoting critical reflection
However, in order to effectively foster an environmentally aware circuit bending practice, two points need to be further analysed. The first point is related to reusing. As we have seen, the ‘reusing’ part of the bending process is not systematically embedded in the practice, but rather it relies much on the practitioner's education, vision, and sensibility. Additionally, the educational material does not systematically suggest strategies to find and use discarded EEDs and, occasionally, it even suggests buying new devices.
The second problem related to circuit bending is that bent instruments tend to age faster than newly designed ones . Therefore, it is particularly relevant to reflect on and consider their maintenance and disposal, possibly even before starting the actual bending. In this sense, the scale from disposal to repair proposed by Blevis  can be particularly of use.
Based on the various themes overviewed and considerations developed in this manuscript, we propose the following set of recommendations for sustainable circuit bending (each of which is detailed below):
To rely on second-hand electronics;
To inform the audience about the reusing process;
To consider future reusing of the material;
To be open.
To rely on second-hand electronics
As a first point, circuit bending should always rely on second-hand electronics, aiming at re-contextualising, remanufacturing, upcycling, and repurposing otherwise disposed of technology. Using still functional and—most importantly—usable devices would contribute to producing new waste, particularly since bent instruments tend to have a shorter life . As we have seen, currently manuals do not deeply investigate an environmentally aware method to source the devices to bend. Therefore, a good evolution in that sense, and a concrete contribution towards practically implementing these recommendations, would be the development of didactic resources dedicated to finding, selecting, and collecting second-hand devices. Although regulations regarding the management of disposed of EEDs differ amongst countries , in order to allow for didactic resources to be effective they should at least contain suggestions on how to proceed in the collection of devices. Additionally, in the long term, such didactic material could help find similarities and develop strategies that can be valid in general, and not only locally coping with the regulations.
To inform the audience about the reusing process
Sustainable circuit bending for artistic purposes should expose the re-contextualisation and reusing process by informing the audience about the environmental implications of the practical and technological choices decided during the bending process. However, the hardware side of the bent instrument is just a facet of the whole. We argue that the ecological and environmental aspects could (and should) be reinforced through artistic reflection as well, and instances related to the post-digital and glitch aesthetics can be valuable in supporting this. While this already happens in practice sometimes (see ), it is not always exposed to the audience. Therefore, we suggest that more focus can be placed on making the repurposing and reusing side of circuit bending more evident to the public through artistic practice. By doing this, the physical and the performative components would become different parts of a whole—with the latter becoming the natural prosecution of the discourse started by the bending process and the physical instrument itself. Therefore, contextualising the entire circuit bending practice through the lenses of post-digital and glitch aesthetics can help the audience to better understand the very ecological and environmental meaning lying beneath the modification of disposed of EEDs, and their artistic use.
To consider future reusing of the material
Bent instruments, accordingly to Ghazala, have a different, usually shorter lifespan with accelerated ageing compared to the non-bent ones . While it is inevitable that they will eventually stop functioning, the real question relates to their doom once they reach their End-Of-Life (EOL). Drawing from Blevis’ categorisation , we propose recycling the components of a burned-out bent instrument as the best way to dismantle it in an environmentally sustainable way. While electric and electronic components can be tested and salvaged, other materials (e.g. the ones composing the case) can be recovered as well—or, if there is no other choice, recycled properly through the canonical waste management system. The resulting hardware can be used as spare parts or as components for bending other EEDs. We acknowledge that this method does not guarantee the total reuse of all the components and materials, but can say with confidence that the majority of them can be repurposed in this way. In addition, following Blevis’ suggestions, if DIY instruments realised from scratch are designed to be recycled, the effectiveness of this solution when there is a need to dispose of them will increase. We argue that this second reuse should be already accounted for in the initial design of the bent instrument, favouring future dis-assemblage and reuse of the components.
To be open
Sustainable circuit bending should aim to document the processes and artefacts, which implies relying as much as possible on open hardware and FLOSS approaches . The openness of the project and resulting hardware has many advantages. One such example is that it can help practitioners to share processes, workarounds, and solutions. Thus, it can prevent or limit the duplication of possible errors and, consequently, waste production. In addition, openness can facilitate future bending, thus prolonging the lifespan of technology, mitigating the problem of disposing of a bent instrument, as we discussed in point 3). In addition, there is to consider that openness offers other collateral advantages. For example, sharing knowledge can help spread the practice and aesthetic of environmentally aware circuit bending in a more effective and widespread way, possibly establishing an informal but valuable corpus of resources.
Drawing from the classification proposed by Mankoff and colleagues , we argue that points 1), 3), and 4) would contribute to addressing environmental sustainability in design, while point 2) primarily addresses this matter through design. In addition, on the track of the work done so far for the NIME Eco Wiki, we argue that creating a similar online space could offer key support for the points we proposed. Such a space, allowing benders to both retrieve and share knowledge, could be of interest in particular for points 1)—to share ways to obtain disposed of devices—and 4)—to share best practices, solutions, and knowledge in general.
To conclude, we underline the potential of circuit bending to be an environmentally aware practice and, through the four points we presented, we hope to strengthen this aspect both in its practical and performative sides. At the same time, we hope to renovate and reinforce the attention and interest for the environment in the scope of circuit bending within the NIME context. Future works should aim at finding ways to operationalise the proposed recommendations.
The first author acknowledges the University of Portsmouth - Faculty of Creative and Cultural Industries for the PhD Studentship supporting this research.
The second author acknowledges ARDITI - Agencia Regional para o Desenvolvimento e Tecnologia under the scope of the Project M1420-
09-5369-FSE-000002 - PhD Studentship and acknowledges the sup-
port of LARSyS to this research (Projeto - UIDB/50009/2020).
Both authors thank Charlie Smith for proofreading this article.
This paper primarily addresses environmental issues related to the practice of circuit bending. Environmental sustainability is one important topic in today's ethical debate, as addressed also in the NIME Code. The content of this paper has not been developed from studies that involved participants and, therefore, no issues related to data management or participants’ safety are relevant for this paper. We acknowledge that this paper fails to address other important ethical topics such as inclusivity and diversity. We also acknowledge that social inclusivity is an important factor to consider in relation to environmental issues, and we support that a follow-up to this paper would be needed to connect the proposed points in light of social inclusivity.