## 1 Introduction  
The concept of virtual acoustics includes a series of computer and acoustic signal processing techniques that allow to study and recreate the acoustic behavior of a room. Virtual acoustics has proven to be a very effective tool for studying heritage enclosure against different variables [1, 2]. However, there is no specific tool for studying the acoustic behavior of an open space with heritage interest. To solve this challenge, different authors have studied the applicability of the tools provided by the acoustics in rooms in the study of open and semi-open heritage soundscapes [3, 4, 5]. In this sense, [PERSON] et al. studied the characteristic loudness of various Roman theater stages using virtual acoustics, a tool commonly used in the acoustic study of rooms [6, 7, 8, 9]. In the same way, [PERSON] et al. performed a virtual reconstruction of the historical acoustics of the The Quantum Tecum of Pompeii [10, 11] and [PERSON] and [PERSON] performed a reconstruction of the acoustic sound field of Stonehenge based on measurements taken at a full-size replica [12]. For his part, [PERSON] analyzed acoustic echoes around the Mayan temple of Kukulkan at Chichen Itza, Mexico [13]. Also of interest is the research carried out by [PERSON] et al., in which they used auralization to recreate the entire soundscape of a specific event, in this case, [PERSON]'s 1622 gumpowder plot sermon at Paul's Cross, outside St. Paul's Cathedral in London, as it was prior to the fire of 1666 [14]. Following the line of these investigations, in the present study, virtual acoustics is applied to acoustically characterize the environment of the Water Tribunal of the Plain of Valencia. This event, declared Intangible cultural heritage of Humanity in 2009 by UNESCO, is the oldest-existing justice institution in Europe [15]. The sessions of the Water Tribunal of the Plain of Valencia take place every Thursday under the Door of the Apostlesof the Cathedral of Valencia, which is an excellent sample of the late Gothic of the Valencian Golden Age [16]. It is a soundscape of great heritage value where the transmission of the word is a preferential factor. The purpose of this work is the analysis of the acoustic conditions in the environment of the Water Tribunal of the Plain of Valencia and its soundscape, characterizing the main sources in this environment to serve as an objective record of the cultural heritage event. This study is intended to contribute to the knowledge for researchers and practitioners in outdoor cultural heritage events. The methodology followed for this work, in the acoustic measurement, is based on the requirements of ISO-3382-1 [17] and some open perspectives in ISO 12913 [18; 19; 20]. The acoustic simulation was carried out with ODEON and CATT-Acoustic software. As a novelty, this research has proven convenient to perform the calibration of the acoustic model with the parameters C80 and C50 instead of with T30, because they turned out to be more stable parameters in the singular environment studied, in contrast with the usual results in closed rooms [21]. A comparison of the results obtained with both acoustics software was carried out to analyze their applicability in the acoustic study of open spaces. For the auralization of event sound, an anechoic recording of recited text during sessions was made. In addition, to give more precision to auralization, the real source of the event was characterized, which is the voice of the bailiff who recites the text. For this, the anechoic chamber located in Universitat Politecnica de Valencia was used. As a result of process, the acoustic and visual simulation of the surroundings of the Water Tribunal of the Plain of Valencia were obtained. Using this simulation, the soundscape has been characterized using the protocol established by [PERSON] et al. [22].