Virtual acoustics displays

The real time acoustic display capabilities are described which were developed for the Virtual Environment Workstation (VIEW) Project at NASA-Ames. The acoustic display is capable of generating localized acoustic cues in real time over headphones. An auditory symbology, a related collection of representational auditory 'objects' or 'icons', can be designed using ACE (Auditory Cue Editor), which links both discrete and continuously varying acoustic parameters with information or events in the display. During a given display scenario, the symbology can be dynamically coordinated in real time with 3-D visual objects, speech, and gestural displays. The types of displays feasible with the system range from simple warnings and alarms to the acoustic representation of multidimensional data or events

Effects of virtual acoustics on dynamic auditory distance perception

Sound propagation encompasses various acoustic phenomena including reverberation. Current virtual acoustic methods, ranging from parametric filters to physically-accurate solvers, can simulate reverberation with varying degrees of fidelity. We investigate the effects of reverberant sounds generated using different propagation algorithms on acoustic distance perception, i.e., how faraway humans perceive a sound source. In particular, we evaluate two classes of methods for real-time sound propagation in dynamic scenes based on parametric filters and ray tracing. Our study shows that the more accurate method shows less distance compression as compared to the approximate, filter-based method. This suggests that accurate reverberation in VR results in a better reproduction of acoustic distances. We also quantify the levels of distance compression introduced by different propagation methods in a virtual environment.Comment: 8 Pages, 7 figure

Archaeology and virtual acoustics. A pan flute from ancient Egypt

This paper presents the early developments of a recently started research project, aimed at studying from a multidisciplinary perspective an exceptionally well preserved ancient pan flute. A brief discussion of the history and iconography of pan flutes is provided, with a focus on Classical Greece. Then a set of non-invasive analyses are presented, which are based on 3D scanning andmaterials chemistry, and are the starting point to inspect the geometry, construction, age and geographical origin of the instrument. Based on the available measurements, a preliminary analysis of the instrument tuning is provided, which is also informed with elements of theory of ancient Greek music. Finally, the paper presents current work aimed at realizing an interactive museum installation that recreates a virtual flute and allows intuitive access to all these research facets

Virtual acoustics of the Cathedral of Cadiz

Among heritage buildings, cathedrals best reflect European cultural identity. In addition to litur-gical activities, with the concurrence of the faithful, cathedrals, in spite of their long reverbera-tion times, develop other cultural activities, with a large audience, and have become spaces of the utmost interest for tourism, with a massive influx of tourists. This paper presents a summary of the Final Degree Project in Fundamentals of Architecture of the first author and describes the process of architectural analysis of the cathedral of Cadiz towards the development of a virtual model of the site. The simulated results are compared with those measured in situ for the preeminent position of the source: the high altarEntre los edificios patrimoniales que mejor reflejan la identidad cultural europea están las catedrales. Además de las actividades litúrgicas, con la concurrencia de los fieles, en ellas se desarrollan, a pesar de sus largos tiempos de reverberación, otras actividades culturales, con numerosa audiencia, y se han convertido en espacios del máximo interés turístico, con masiva afluencia de turistas. En este trabajo se hace un resumen del Trabajo Fin de Grado en Fundamentos de Arquitectura del primer autor. En él se describe el proceso de análisis arquitectónico de la catedral de Cádiz con el objetivo de elaborar un modelo virtual del recinto y se comparan los resultados simulados con los medidos in situ, para la posición preminente de la fuente sonora: el altar mayo

Virtual acoustics of the roman theatre of Italica

Classic outdoor theatres have special significance in the universal, cultural and architectural her-itage. These scenic environments have undergone acoustic research in ERATO European project with basic purposes of recreation of associated intangible heritage and for their adaptation to contemporary cultural performances. In this work, the Roman theatre of the archaeological site of Italica (Seville) is studied by means of acoustic simulation, which responds to the classical scheme: cavea, orchestra, scenae, four-sided portico, and a capacity for 3,000 spectators. Throughout this paper, the creation process, adjustment, and validation of the 3D model of the theatre for simulating its sound field is analysed, which is based on the experimental measure-ment of reverberation time. The initial model, once validated, is modified to assess the acoustic impact of various proposed interventions.Los teatros clásicos al aire libre tienen muy especial significación en el patrimonio arquitectónico y cultural universal. Estos entornos escénicos han sido objeto de investigación acústica en el proyecto europeo ERATO, con fines básicos de recreación del patrimonio inmaterial asociado y para su adaptación a espectáculos culturales contemporáneos. En este trabajo se estudia me-diante simulación acústica el teatro romano del conjunto arqueológico de Itálica (Sevilla), el cual responde al esquema clásico: cavea, orchestra, scenae, pórtico de cuatro lados, y un aforo para 3.000 espectadores. A lo largo de la comunicación se analiza el proceso de creación, ajuste y validación del modelo 3D del teatro para la simulación de su campo sonoro, apoyado en los ensayos experimentales del tiempo de reverberación. Una vez validado, el modelo inicial se ha modificado con objeto de evaluar el impacto acústico de varias intervenciones propuestas

Virtual acoustics of the Cathedral of Malaga (Spain)

The Catholic Cathedral of Malaga (southern Spain), located in the historical centre, is the most emblematic building of the city. Its construction began in 1528 and was completed in 1782, suffering several interruptions and modifications at the hands of various architects, and hence various architectural styles are superimposed: the interior is Renaissance and the façade is predominantly Baroque. Rectangular in shape, it has three naves of the same height, with the central nave being the widest. In this work, a 3D model of this ecclesiastical space is created in order to carry out an acoustic simulation of its sound field by using the simulation algorithms of CATT Acoustic software implemented in the new TUCT calculation motor (The Universal Cone Tracer). The virtual model created is calibrated through an iterative process of adjustment of reverberation times simulated in such a way that they differ by no more than 5% from those measured. These measured values were obtained from the impulse responses monitored in situ. Likewise, a comparison of the experimental and simulated results of other acoustic parameters in terms of their just noticeable differences (JND) was also carried out, which supports the reliability of the computational acoustic model implemented. This work is the starting point of a multidisciplinary project which aims to incorporate the acoustic aspects within the heritage value of Andalusian cathedral