3D Time-Based Aural Data Representation Using D4 Library’s Layer Based Amplitude Panning Algorithm

Presented at the 22nd International Conference on Auditory Display (ICAD-2016)The following paper introduces a new Layer Based Amplitude Panning algorithm and supporting D4 library of rapid prototyping tools for the 3D time-based data representation using sound. The algorithm is designed to scale and support a broad array of configurations, with particular focus on High Density Loudspeaker Arrays (HDLAs). The supporting rapid prototyping tools are designed to leverage oculocentric strategies to importing, editing, and rendering data, offering an array of innovative approaches to spatial data editing and representation through the use of sound in HDLA scenarios. The ensuing D4 ecosystem aims to address the shortcomings of existing approaches to spatial aural representation of data, offers unique opportunities for furthering research in the spatial data audification and sonification, as well as transportable and scalable spatial media creation and production

Psychoacoustic Considerations in Surround Sound with Height

This paper presents recent research findings in the psychoacoustics of 3D multichannel sound recording and rendering. The addition of height channels in new reproduction formats such as Auro-3D, Dolby Atmos and 22.2, etc. enhances the perceived spatial impression in reproduction. To achieve optimal acoustic recording and signal processing for such formats, it is first important to understand the fundamental principles of how we perceive sounds reproduced from vertically oriented stereophonic loudspeakers. Recent studies by the authors in this field provide insights into how such principles can be applied for practical 3D recording and upmixing. Topics that are discussed in this paper include the interchannel level and time difference relationships in terms of vertically induced interchannel crosstalk, the effectiveness of the precedence effect in the vertical plane, the aspect of tonal coloration resulting from vertical stereophonic reproduction, the effect of vertical microphone spacing on envelopment, the effect of interchannel decorrelation, and the use of spectral cues for extending vertical image spread

Effect of Vertical Microphone Layer Spacing for a 3D Microphone Array

Subjective listening tests were conducted to investigate how the spacing between main (lower) and height (upper) microphone layers in a 3D main microphone array affects perceived spatial impression and overall preference. Four different layer spacings of 0m, 0.5m, 1m, and 1.5m were compared for the sound sources of trumpet, acoustic guitar, percussion quartet, and string quartet using a nine-channel loudspeaker setup. It was generally found that there was no significant difference between any of the spaced layer configurations, whereas the 0m layer had slightly higher ratings than the more spaced layers in both spatial impression and preference. Acoustical properties of the original microphone channel signals as well as those of the reproduced signals, which were binaurally recorded, were analyzed in order to find possible physical causes for the perceived results. It is suggested that the perceived results were mainly associated with vertical interchannel crosstalk in the signals of each height layer and the magnitude and pattern of spectral change at the listener’s ear caused by each layer

Surround by Sound: A Review of Spatial Audio Recording and Reproduction

In this article, a systematic overview of various recording and reproduction techniques for spatial audio is presented. While binaural recording and rendering is designed to resemble the human two-ear auditory system and reproduce sounds specifically for a listener’s two ears, soundfield recording and reproduction using a large number of microphones and loudspeakers replicate an acoustic scene within a region. These two fundamentally different types of techniques are discussed in the paper. A recent popular area, multi-zone reproduction, is also briefly reviewed in the paper. The paper is concluded with a discussion of the current state of the field and open problemsThe authors acknowledge National Natural Science Foundation of China (NSFC) No. 61671380 and Australian Research Council Discovery Scheme DE 150100363

An Exploration and Analysis of 3D Audio

3D and Binaural audio, these are two concepts that are coming up more frequently in the audio domain as the world of virtual reality grows. With this growth as an audio engineer we may see a major change within the years ahead. Whether it be new methods of receiving media, or new jobs that may be created. This paper will look at these concepts to see what may possibly be ahead of us. What my paper will touch on is the history of 3D and binaural audio, the differences between 3D and binaural audio, how 3D and binaural audio work,The different types of binaural mics and software, recording techniques with binaural mics, Listening environments, and experimental uses of 3D and binaural audio. With this research and understanding the paper will look at the possibilities for the future uses of these technologies and how that could affect the multi-media industries

Tissue-conducted spatial sound fields

We describe experiments using multiple cranial transducers to achieve auditory spatial perceptual impressions via bone (BC) and tissue conduction (TC), bypassing the peripheral hearing apparatus. This could be useful in cases of peripheral hearing damage or where ear-occlusion is undesirable. Previous work (e.g. Stanley and Walker 2006, MacDonald and Letowski 2006)1,2 indicated robust lateralization is feasible via tissue conduction. We have utilized discrete signals, stereo and first order ambisonics to investigate control of externalization, range, direction in azimuth and elevation, movement and spaciousness. Early results indicate robust and coherent effects. Current technological implementations are presented and potential development paths discussed

An investigation into the perception of spatial techniques used in multi-channel electroacoustic music

The paper reports on an experiment designed to examine the perception of the spatial attributes of envelopment and engulfment in spatial techniques used in multichannel electroacoustic music. Four spatial techniques were examined, they were: (i) Timbre Spatialisation [1], (ii) Spectral Splitting [2], (iii) Amplitude Point Source [3], and the proposed (iv) Dynamic Spectral Spatialisation technique. The multi-channel loudspeaker configuration consisted of 16 loudspeakers, eight horizontal and eight elevated. The experiment was design whereby the four above mentioned spatial techniques were presented in three conditions: (i) Horizontal only, (ii) Elevated only, and (iii) Horizontal and Elevated, referred to as Three Dimensional (3D), loudspeaker configurations. The experiment took place in the Spatialisation Auditory Display Environment (SpADE) at the University of Limerick and has physical attributes that conform to the ITU-R BS.1116-1 listening room standard [4]. Each participant individually undertook a listening experiment whereby they were asked to evaluate each spatial technique presented in the three conditions for perceived levels of envelopment and engulfment. A factorial analysis of variance (ANOVA) was performed on the envelopment and engulfment ratings. The results of the analysis revealed a significant main effect for spatial techniques and loudspeaker configurations for both spatial attributes. Participants rated the Dynamic Spectral Spatialisation technique highest for levels of envelopment and engulfment. The Horizontal loudspeaker configuration was rated highest for envelopment and the Elevated loudspeaker configuration was rated highest for engulfment

The Reduction of Vertical Interchannel Crosstalk: The Analysis of Localisation Thresholds for Natural Sound Sources

In subjective listening tests, natural sound sources were presented to subjects as vertically-oriented phantom images from two layers of loudspeakers, ‘height’ and ‘main’. Subjects were required to reduce the amplitude of the height layer until the position of the resultant sound source matched that of the same source presented from the main layer only (the localisation threshold). Delays of 0, 1 and 10 ms were applied to the height layer with respect to the main, with vertical stereophonic and quadraphonic conditions being tested. The results of the study showed that the localisation thresholds obtained were not significantly affected by sound source or presentation method. Instead, the only variable whose effect was significant was interchannel time difference (ICTD). For ICTD of 0 ms, the median threshold was −9.5 dB, which was significantly lower than the −7 dB found for both 1 and 10 ms. The results of the study have implications both for the recording of sound sources for three-dimensional (3D) audio reproduction formats and also for the rendering of 3D images