# Using Virtual Soundwalk Approach for Assessing Sound Art Soundscape Interventions in Public Spaces
## 1 Introduction
[45] found out that a unique integrally designed soundscape intervention can lead to an almost enthralled assessment, which included the Sea Organ installation in Zadar. Their results showed high ratings of presumably opposite positive soundscape perception descriptors--calmness and excitement. By using laboratory listening tests based on in situ measurements, [PERSON] et al. [44] acknowledged a significant shift towards 'positive soundscape descriptors' when generic music was introduced during the festive season in urban open spaces otherwise monotonous and characterized mainly by traffic noise. [PERSON] et al. [8] acknowledged the positive influence sound art interventions in a public space in Montreal had on the perceived calmness and pleasantness. However, while acoustic and psychoacoustic properties of water features added to public spaces were often in the focus of soundscape researchers [22; 51; 52], none of the studies reported in depth on the psychoacoustic properties of the added musical sound sources. Soundscape interventions investigated in literature featured case studies surveyed on-site and others recreated through laboratory simulations, covering both suppressing sounds (i.e., testing different noise barrier characteristics using virtual reality [38]) and adding sound sources. Laboratory studies are generally considered an ecologically valid tool for soundscape assessments per ISO/TS 12913-3: 2019, especially when using Ambisonics reproduction [53; 54], despite limitations and concerns raised by some researchers [25]. Moreover, reproduction techniques in laboratory conditions proved to have a negligible effect on the essential soundscape descriptors featured in ISO/TS 12913-2: 2018 [30; 55; 56]. Some of the above-mentioned studies were looking into the soundscape interventions 'as they are' [42; 45]. Other were trying to assess their impact by defining a baseline condition and then looking into the conditions such as 'on and off'/'with or without' [44; 57], 'before and after' [1; 7] or comparing different scenarios and exposure conditions [4; 5; 38; 58]. In terms of selecting key conditions, different time frames were featured, spanning from several years between the conditions [36; 44] to several minutes in the same time of day [4]. In the case of soundscape interventions that are built as an integral part of an architectural design, perhaps the 'before and after' scenario might not be appropriate, as it is implied that context as a whole changes significantly during the design process which would then take the focus away from the acoustic environment. On the other side, some soundscape interventions, such as the Sea Organ in Zadar, cannot be easily switched off. Finding an optimal, most ecologically valid way to assess soundscape interventions remains an open task, crucial for future soundscape planning and design. This study is looking at the effectiveness of a virtual soundwalk approach [39]. In a virtual soundwalk, participants keep a clear understanding of the spatial relation between the measurement points as in a soundwalk in situ, while the research benefits from the convenience and high level of standardization of test conditions ensured in the laboratory environment. This study aims to test:  
* if the SSQP is effective for assessing impact of a soundscape intervention featuring sound art in terms of: (1) sound source identification, (2) perceptual attributes, and (3) appropriateness;
* if a virtual soundwalk with two measurement points within a single urban open space approach is appropriate to figure as a tool for an experiment featuring baseline and exposure conditions;
* psychoacoustic properties of sound sources added within the'musical soundscape intervention' in an urban open space.