Acta Acustica United With Acustica 

About: Acta Acustica United With Acustica is an academic journal. The journal publishes majorly in the area(s): Noise & Sound pressure. It has an ISSN identifier of 1861-9959. Over the lifetime, 1572 publications have been published receiving 20183 citations.

Auditory distance perception in humans : A summary of past and present research

Abstract: Although auditory distance perception is a critical component of spatial hearing, it has received substantially less scienti.c attention than the directional aspects of auditory localization. Here we summarize current knowledge on auditory distance perception, with special emphasis on recent research results. The summary will be structured around three central questions. 1. How accurately can humans estimate the distances of stationary sound sources? We show that this psychophysical relationship is well approximated by a compressive power function, which suggests that listeners systematically underestimate distances to faraway sound sources. 2. What determines perceived sound source distance? We examine the various acoustical and non-acoustical factors thought to contribute to source distance percepts, and summarize the psychophysical literature relevant to each factor. 3. What are the neural correlates to perceived sound source distance? Recent evidence points to the role of areas within right temporal cortex in auditory distance perception, as well as in other spatial tasks in different sensory modalities.

Acoustic Indices for Biodiversity Assessment and Landscape Investigation

Abstract: Jérôme Sueur1), Almo Farina2), Amandine Gasc1,3), Nadia Pieretti2), Sandrine Pavoine3,4) 1) Muséum national d’Histoire naturelle, Département Systématique et Évolution, UMR 7205-CNRS ISYEB, 45 rue Buffon, Paris, France. sueur@mnhn.fr 2) Department of Basic Sciences and Foundations, Urbino University, Urbino, Italy 3) Muséum national d’Histoire naturelle, Département Ecologie et Gestion de la Biodiversité, UMR 7204 CNRS-UPMC CESCO, 55-61 rue Buffon, 75005 Paris, France 4) Mathematical Ecology Research Group, Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK

Three-dimensional non-refrective boundary conditions for acoustic simulation : far field formulation and validation test cases

Abstract: Summary In aeroacoustic simulations, non-reflective boundary conditions are necessary to minimize the acoustic waves reflected when disturbances leave the computational domain. In the present paper, far field boundary conditions are developed for a 3-D geometry. Two validation test cases involving respectively an acoustic pulse and an axisymmetric ring vortex in a uniform mean flow are also proposed. The solutions from linearized Euler equations show that the far field boundary conditions allow the exit of acoustic waves without generating significant spurious waves. The exit of vortical disturbances is more difficult to treat with efficiency because of their high magnitude. For this case, the implementation of a sponge zone is presented to decrease the amplitude of acoustic reflections.

A cognitive approach to urban soundscapes : Using verbal data to access everyday life auditory categories

Abstract: The present research on cognitive categories mediates between individual experiences of soundscapes and collective representations shared in language and elaborated as knowledge. This approach focuses on meanings attributed to soundscapes in an attempt to bridge the gap between individual perceptual categories and sociological representations. First, results of several free categorisation experiments are presented, namely the categorical structures elicited using soundscape recordings and the underlying principles of organisation derived from the analysis of verbal comments. People categorised sound samples on the basis of semantic features that integrate perceptual ones. Specifically, soundscapes reflecting human activity were perceived as more pleasant than soundscapes where mechanical sounds were predominant. Second, the linguistic exploration of free-format verbal description of soundscapes indicated that the meanings attributed to sounds act as a determinant for sound quality evaluations. Soundscape evaluations are therefore qualitative first as they are semiotic in nature as grounded in cultural values given to different types of activities. Physical descriptions of sound properties have to be reconsidered as cues pointing to diverse cognitive objects to be identified first rather as the only adequate, exhaustive and objective description of the sound itself. Finally, methodological and theoretical consequences of these findings are drawn, highlighting the need to address not only noise annoyance but rather sound quality of urban environments. To do so, cognitive evaluations must be conducted in the first place to identify relevant city users' categories of soundscapes and then to use physical measurement to characterize corresponding acoustic events.

Soundscape quality in suburban green areas and city parks.

Abstract: According to guidelines proposed in Sweden, at least 80% of the visitors in quiet areas should perceive the sound environment as good This was the starting point for a questionnaire study on "soundscape quality" in four suburban green areas and in four city parks The soundscapes in the suburban areas were completely dominated by sounds from nature (eg, bird song and sounds from water), whereas traffic noise was a main component of the city-park soundscapes Measured equivalent sound levels (from all sources) ranged from 42 to 50 dBA in the suburban green areas, and from 49 to 60 dBA in the city parks (L Aeq,15min ) "Soundscape quality" was assessed by a five-point bipolar category scale Among the respondents, 84-100% in the suburban green areas and 53-65% in the city parks assessed the soundscape as "Good" or "Very good" Thus, all suburban green areas but none of the city parks reached the stipulated goal (at least 80%) The soundcape quality was confirmed by attribute profiling using a set of 12 adjectives Based on the visitor's responses, it is concluded that good soundscape quality can only be achieved if the traffic noise exposure in suburban green areas and city parks during day time is below 50 dBA