# The Soundscape Hackathon as a Methodology to Accelerate Co-Creation of the Urban Public Space
## 1 Introduction  
The creation of new urban environments used to be the responsibility of architects, urban designers and local authorities. Only recently, the role of the citizen has changed to becoming a partner in a co-creation process [1]. This new form of direct participation allows to more directly include the elements that the local population considers as important for liveability of the area [2]. It has been recognized since many years that environmental noise is a main contributing factor to the liveability of an environment [3].  
Recently, the awareness has grown that the soundscape of a space is equally important as its visual aesthetics [4, 5]. The term soundscape refers to the acoustic environment as perceived by people, in a certain context [6]. Therefore soundscape design aims to (partly) alter that perception or the acoustic environment itself, treating sound as a resource rather than a waste. Not all environmental sounds are noisy or disturbing and should be avoided. Some sounds should be preserved or even accentuated, because a matching soundscape may support the identity and atmosphere (e.g., lively, calming) of the space [7, 8, 9, 10].  
Sound architects that are involved in the sonic design of urban spaces have a broad range of techniques at their disposal. Examples are in- and out-door auralization models, which aim to recreatean aural impression of the acoustic characteristics of a space [11], as well as efficient and realistic acoustic simulation, and immersive audio-visual reproduction systems [12]. Virtual reality (VR) and the combination of it with the aforementioned techniques are possibly the most powerful tools currently available. VR is very affordable and not that difficult to work with. It gives the users the impression of being physically present in the environment and allows them to interact with it in real time [13; 14; 15]. These techniques are very appealing to both experts and non-experts, and hold new opportunities to motivate urban designers to consider soundscape design, thereby aiming to have a positive impact on the everyday users of the space.  
This paper puts forward the concept of a soundscape hackathon, on the one hand as a way to generate tools and methodologies for co-creating the urban sound environment, on the other hand to explore and demonstrate creative ideas for soundscape design. A Soundscape Hackathon was organized as a satellite event to the Urban Sound Symposium, which took place on 3-5 April 2019. The combination of both events attracted acousticians, sound engineers, artists, city representatives, architects as well as urban planners, representing a broad mix of backgrounds that is very valuable in the context of co-creation. The hackathon event took place at De Krook, the new media center in Ghent that houses the city library, imec and different research groups of Ghent University, among which the Institute for Psychoacoustics and Electronic Music (IPEM).  
This paper is organised as follows. In Section 2, the general hackathon approach is discussed. In Section 3, the Soundscape Hackathon is described as it was organized by the authors, including task description, team recruitment, information about the provided soundscape data set, the available equipment and the criteria the evaluation was based on. Section 4 then presents the scenarios developed by the different teams. Subsequently, in Section 5, a critical discussion about the hackathon and its goals is presented. Finally, in Section 6, the suitability of the soundscape hackathon as a method to generate creative approaches for improving the urban sound environment in co-operation with various stakeholders is evaluated.