5.1. Hackathon Outcomes
The main goal of including creativity in the evaluation criteria was to promote outside-the-box thinking in generating creative ideas for more fitting soundscapes. A common thread in all presented interventions is the use of green elements, or more generally, elements from nature. Green spaces in particular are attractive for several reasons: they encourage social interaction, stimulate physical activity and give opportunities for mental restoration [
50]. Moreover, the beneficial effect of green elements on the urban soundscape is well documented in literature, see for example [
7,
51]. Although all presented interventions focus in some way on nature-related aspects, the four teams took a different conceptual approach. Team Noize Makers emphasized and improved existing elements, for instance bird sounds or a fountain in the background. Teams URCHI and Trio Akustiko added additional green elements, such as a dome overgrown with ivy (URCHI), or even an entire scene with hills and trees (Trio Akustiko). Three teams gave materialized support for the services the green provides: wind chimes or a fountain for relaxing sounds (URCHI, Trio Akustiko), a cafe for social interaction (Trio Akustiko), resting benches for mental restoration (Trio Akustiko, Immensive) or gym exercise equipment for stimulating physical activity (Immensive). One could consider the gym stand to be superfluous, since the park itself gives plenty of opportunities for performing similar excercises. However, these installations add the potential of social interaction to the physical stimulation, as it may function as an attraction point in the park. The presence of green elements is strongly related to the tranquility of a space. In general, three groups of people can be discerned based on how they attach meaning to the concept of tranquility. They either associate it with silence, natural sounds or social relationships [
52]. Approaches that emphasize existing green elements (Noize Makers), or that involve adding new green elements (URCHI), address the need for natural sounds and to a lesser extent also the need for silence. Approaches that support the services for social interaction that the greenery provides (Immensive, Trio Akustiko), address the importance of social relationships. Although it is not required that all viewpoints on tranquility are covered in each urban place, it would be advantageous that all teams in a hackathon consider them. To this end, it is necessary to have a well balanced team with participants covering these different viewpoints.
Theoretical soundness was included in the evaluation criteria in order to counterbalance creativity, as it should be physically feasible to implement those creative ideas in the urban scene. Additionally they should make sense, in order to effectively increase the quality of the soundscape. All teams spent a considerable amount of effort to make their designs sound plausible. However, the extent to which the solutions could be implemented in real life varies considerably. Interventions such as those in New York City Hall Park (Noize Makers) are meant to be implemented on top of existing scenery, without physically altering the real environment, and could be relatively easily implemented. Other interventions, such as those at Potsdamer Platz (Trio Akustiko) or at the Rose Fitzgerald Kennedy greenway in Boston (URCHI) would require considerable landscaping efforts to realize. Moreover, they would require considerable changes to the original design in order to make sense acoustically because the acoustical screening effects are overestimated in the initial auralization. This illustrates some of the pitfalls of co-creation: firstly, participants may violate the laws of physics due to a lack of knowledge; secondly, some factors might be neglected, for instance the cost of implementing a new design; thirdly, some indirect effects, e.g., the flow of persons in emergency situations, may not be considered adequately due to lack of expert knowledge in particular fields.
The use of technology as an evaluation criterium assesses the way the teams made use of the available tools to present their ideas in a convincing way. As discussed in
Section 3.4, the hackathon participants had a wide range of visualization and audio rendering techniques at their disposal for presenting their solutions. The results of the hackathon show that (a combination of) the current technologies allow to audio-visually present the redesign of a space in a limited time frame of two days and with relatively good quality.
On the one hand, most interventions revolved around adding sounds, which is reflected in the dominant choice of rather quiet (e.g., Montreal McGill University Campus) or relatively confined spaces (e.g., New York City Hall Park or Hong Kong Signal Hill Garden). Added sounds are sometimes visually accentuated during the presentation, such as in the intervention in New York City Hall Park (Noize Makers), where special legend objects guide attention to selected interventions. For the interventions in Potsdamer Platz (Trio Akustiko) and the McGill University Campus (Immensive), accentuation during presentation is less critical, as the added objects are rendered differently on top of the original visual scene and already focus attention. However, these objects may lose appreciation of their added functionality since they visually dominate the scenery. As a result, having a balance between attracting attention and becoming part of the scenery is an important rendering aspect for creating the VR outcome. On the other hand, two interventions involved suppressing existing sounds: the added hills at the Potsdamer Platz (Trio Akustiko), and the dome at the Boston greenway (URCHI). With most audio rendering software or VR engines, new sounds can be added relatively easily to an existing soundscape. Suppressing existing sounds originating from a particular direction poses a greater technical challenge. Given the limited time available, both teams provided a first impression of the effect of their intervention by reducing and spectrally shaping the ambient soundscape as a whole, approximating the physics of sound propagation involved. Nevertheless, in order to allow participants to investigate the full potential of suppressing existing sounds, future soundscape hackathons should consider providing easy-to-use software tools for sound propagation, such that participants can focus on the creative aspect rather than on physics.
Another common aspect in all interventions, particularly made possible through the use of VR technology, is the interaction between the user and its environment. Interaction, where the user of a space can to some extent take control of its soundscape, creates a larger sense of presence and immersion, and therefore may make the presentation more convincing. Basic forms of interaction with which the user can shape its soundscape were included in several interventions, such as the sound of footsteps when walking in the Boston greenway (URCHI) or the sound of the gym tools (e.g., the moving water of the rowing machine) at the McGill University Campus (Immensive). In more advanced forms of interaction, users are able to manipulate objects inside the VR environment in order to create sound or alter the soundscape. This requires haptic feedback devices, which were not available in this hackathon. Future soundscape hackathons would therefore benefit from having such tools at the disposal, allowing participants to design sound environments with a higher level of interactivity.
5.2. Evaluation of the Event
As this was the first soundscape hackathon, the authors acknowledge that there is still room to improve the organization of the event. To receive feedback and to gain more insight into the organization of the event, a small questionnaire for evaluation was distributed among participants, jury members and those attendees of the Urban Sound Symposium that registered to attend the final presentations and demonstrations. The questionnaire included a mix of rating questions and open-ended question and dealt with, among other topics, format, general appreciation, and suggestions on improvements. Because the number of respondents was small, the questionnaire was not used as a statistic way to evaluate the event, but rather as an inspiration for improvement. In general, the event was perceived as creative and interesting, and certainly to be repeated. Combined with how the organizers experienced the event, three main points of improvement could be extracted from the questionnaire responses.
A first point of improvement is the selection of participants. As the event was inherently connected to the Urban Sound Symposium and was shared among the academic and professional network of the organizers, participants mainly were acousticians and sound professionals with a technical background. According to the respondents, other parties should be invited as well, including artists, architects, city representatives, public space designers, software developers and residents (in order of importance as stated by the respondents). Given a wider mix of participant backgrounds, more creative ideas could have emerged.
Secondly, due to the organization of the event in parallel to the Urban Sound Symposium, the jury members were not able to visit the teams during the hackathon itself. To decide on a winner for the Soundscape Hackathon, the jury members individually gave points on the three evaluation criteria to obtain an overall score for each team, thus making it an outcome-centered evaluation. Several respondents suggested to have multiple smaller awards for different sub-challenges, instead of one team winning everything. This could reduce the competitive nature of the event and instead stimulate cooperation, possibly leading to better results. One could assess the degree of collaboration within and between the teams as an extra criterion or as a sub-challenge, next to the quality of the work. In the outcome-centered evaluation as it was, Team Noize Makers was declared as the winning team and received a trophy and a monetary award.
Thirdly, the organization and timing of the final presentations can definitively be improved. Given the short duration available for the final presentations and the use of the same equipment by different teams, it was hard to coordinate efficiently and to provide access to a broader audience. However, in context of co-creation, the presence of and the interaction with a broader audience can reflect the participation of local residents. Even an award based on the score of the audience could be included, as suggested by the respondents, instead of only having a jury to provide scores.
The Soundscape Hackathon was organized to explore the potential of the hackathon format in a co-creation context for generating creative concepts, methods and tools to increase the quality of the soundscape of urban outdoor spaces. To achieve this goal, the aforementioned improvements must be taken into account. The hackathon should bring together a wide mix of stakeholders to enhance their project participation. Evaluation should be based not only on the outcome of the presented work, but the interaction of the hackathon teams with each other and with the different stakeholders will have to be integrated in the hackathon process, and should be taken into account in the evaluation. In this case, the composition of the jury will need to reflect the different stakeholders and will need to be extended with moderating professionals. When also a broad audience of local residents can attend final presentations or can even actively participate, new opportunities for co-creation arise.