Estimating Sound Exposure Levels Due to a Broadband Source over Large Areas of Shallow Sea

3D sound propagation modeling in the context of acoustic noise monitoring problems is considered. A technique of effective source spectrum reconstruction from a reference single-hydrophone measurement is discussed, and the procedure of simulation of sound exposure level (SEL) distribution over a large sea area is described. The proposed technique is also used for the modeling of pulse signal waveforms at other receiver locations, and results of a direct comparison with the pulses observed in the experimental data is presented.

Presence of Three-Dimensional Sound Field Facilitates Listeners’ Mood, Felt Emotion, and Respiration Rate When Listening to Music

Many studies have investigated the effects of music listening from the viewpoint of music features such as tempo or key by measuring psychological or psychophysiological responses. In addition, technologies for three-dimensional sound field (3D-SF) reproduction and binaural recording have been developed to induce a realistic sensation of sound. However, it is still unclear whether music listened to in the presence of 3D-SF is more impressive than in the absence of it. We hypothesized that the presence of a 3D-SF when listening to music facilitates listeners’ moods, emotions for music, and physiological activities such as respiration rate. Here, we examined this hypothesis by evaluating differences between a reproduction condition with headphones (HD condition) and one with a 3D-SF reproduction system (3D-SF condition). We used a 3D-SF reproduction system based on the boundary surface control principle (BoSC system) to reproduce a sound field of music in the 3D-SF condition. Music in the 3D-SF condition was binaurally recorded through a dummy head in the BoSC reproduction room and reproduced with headphones in the HD condition. Therefore, music in the HD condition was auditorily as rich in information as that in the 3D-SF condition, but the 3D-sound field surrounding listeners was absent. We measured the respiration rate and heart rate of participants listening to acousmonium and pipe organ music. The participants rated their felt moods before and after they listened to music, and after they listened, they also rated their felt emotion. We found that the increase in respiration rate, the degree of decrease in well-being, and unpleasantness for both pieces in the 3D-SF condition were greater than in the HD condition. These results suggest that the presence of 3D-SF enhances changes in mood, felt emotion for music, and respiration rate when listening to music.

3D sound spatialization with game engines: the virtual acoustics performance of a game engine and a middleware for interactive audio design

This study analyses one of the most popular game engines and an audio middleware to reproduce sound according to sound propagation physics. The analysis focuses on the transmission path between the sound source and the receiver. Even if there are several ready-to-use real-time auralization platforms and software, game engines' use with this aim is a recent study area for acousticians. However, audio design needs with game engines and the limits of their basic releases require additional tools (plugins and middleware) to improve both the quality and realism of sound in virtual environments. The paper discusses the use of Unreal Engine 4 and Wwise's 3D audio production methods in a set of different test environments. It assesses their performance in regard to a commercial geometrical acoustics software. The results show that the investigated version of the game engine and its sound assets are insufficient to simulate real-world cases and that significant improvements can be achieved with use of the middleware.

Immersed in Pop

In 2019, Dolby Atmos Music launched on Tidal HiFi and Amazon Prime Music HD, integrating 3D sound with music streaming services for the first time. This is one of several recent incursions by popular music into immersive and interactive mediums, which also includes technologies such as virtual reality and 360-degree video. As immersive productions become more normal in popular music, they are increasingly critical to examine. How are aesthetic features of pop compositions altered or maintained in these productions? And how do these different spatial mediums affect compositional design, subject positioning, artists’ performativity, and staging? This article aims to address these questions by presenting a model for 3D music analysis that relates various notions of music technology and production to musicological concepts on performance environment, staging, and subject position. This model is then demonstrated in a hermeneutic close reading of the song ‘Blinding Lights’ by R&B superstar The Weeknd, which was released in both stereo and Dolby Atmos mediums in 2019. The goal of the analysis is to demonstrate some of the ways different mediums impinge on various interpretive stances and the relationship between the performer and listener in immersive popular music.

Quantification of the Psychoacoustic Effect of Noise from Small Unmanned Aerial Vehicles

This paper presents the results of a study evaluating the human perception of the noise produced by four different small quadcopter unmanned aerial vehicles (UAVs). This study utilised measurements and recordings of the noise produced by the quadcopter UAVs in hover and in constant-speed flight at a fixed altitude. Measurements made using a ½″ microphone were used to calculate a range of different noise metrics for each noise event. Noise recordings were also made using a spherical microphone array (an Eigenmike system). The recordings were reproduced using a 3D sound reproduction system installed in a large anechoic chamber located at The University of Auckland. Thirty-seven participants were subjected to the recordings and asked to rate their levels of annoyance in response to the noise, and asked to perform a simple cognitive task in order to assess the level of distraction caused by the noise. This study discusses the noise levels measured during the test and how the various noise metrics relate to the annoyance ratings. It was found that annoyance strongly correlates with the sound pressure level and loudness metrics, and that there is a very strong correlation between the annoyance caused by a UAV in hover and in flyby at the same height. While some significant differences between the distraction caused by the UAV noise for different cases were observed in the cognitive distraction test, the results were inconclusive. This was likely due to a ceiling effect observed in the participants’ test scores.

Perception of noise from small quadcopter UAVs

This paper presents the results of a study evaluating the human perception of the noise produced by small quadcopter UAVs. The study utilised recordings of the noise produced by several different quadcopter UAVs in hover and in constant-speed flight at a fixed altitude. These recordings were made using an eigenmic system. The recordings were reproduced using a 3D sound reproduction system located in the large anechoic chamber at the University of Auckland. Human subjects were asked to rate the annoyance of the recordings. The responses of the test subjects are presented and these are compared with objective metrics to assess suitable metrics for quantifying the impact of noise from these vehicles on humans.

Pilot studies of noise annoyance in relation to time, amplitude and frequency characteristics of sound

Noise is any unwanted sound that may be disruptive or harmful to health or increase the risk of an accident at work. Noise as a stressor can contribute to the development of various types of diseases, cause distraction, make work difficult and reduce its efficiency. Aim of the pilot studies was to asses noise annoyance in relation to time, amplitude and frequency characteristics of sound in typical office environment. The Vienna Test System was used for this purpose. Virtual office acoustic environments were developed with different psychoacoustic parameters, but with a constant A-weighted sound pressure level of 55 dB - environment with conversations, environment with office equipment (computers, printers, telephones), environment D with all office noise sources together. The reference environment was a quiet office room with no additional noise sources. Recorded real noise sources were transferred to a virtual 3D sound environment and converted into binaural sound, which was then played back on headphones. During the exposure to each of the acoustic environments, the subjects performed the ALS test (work performance series) and then assessed the given environment using a questionnaire. The tested acoustic environments were assessed in the range from not at all annoying to very annoying. On average, environments with office noise were rated as moderately annoying. However, subjective feelings of the respondents were not reflected in the results of psychological tests.

Novel Position Estimation using Differential Timing Information for Asynchronous LTE/NR Networks

Positioning techniques have been a common objective since the early development of wireless networks. However, current positioning methods in cellular networks, for instance, are still primarily focused on the use of the Global Navigation Satellite System (GNSS), which has several limitations, like high power drainage and failure in indoor scenarios. This study introduces a novel approach employing standard LTE signaling in order to provide high accuracy positioning estimation. The proposed technique is designed in analogy to the human sound localization system, eliminating the need of having information from three spatially diverse Base Stations (BSs). This is inspired by the perfect human 3D sound localization with two ears. A field study is carried out in a dense urban city to verify the accuracy of the proposed technique, with more than 20 thousand measurement samples collected. The achieved positioning accuracy is meeting the latest Federal Communications Commission (FCC) requirements in the planner dimension.

3D Sound Coding Color for the Visually Impaired

Contemporary art is evolving beyond simply looking at works, and the development of various sensory technologies has had a great influence on culture and art. Accordingly, opportunities for the visually impaired to appreciate visual artworks through various senses such as auditory and tactile senses are expanding. However, insufficient sound expression and lack of portability make it less understandable and accessible. This paper attempts to convey a color and depth coding scheme to the visually impaired, based on alternative sensory modalities, such as hearing (by encoding the color and depth information with 3D sounds of audio description) and touch (to be used for interface-triggering information such as color and depth). The proposed color-coding scheme represents light, saturated, and dark colors for red, orange, yellow, yellow-green, green, blue-green, blue, and purple. The paper’s proposed system can be used for both mobile platforms and 2.5D (relief) models.