Has Ambisonics Come of Age?

The Journal of the Acoustical Society of America, 2021

Reverberation is essential for the realistic auralisation of enclosed spaces. However, it can be computationally expensive to render with high fidelity and, in practice, simplified models are typically used to lower costs while preserving perceived quality. Ambisonics-based methods may be employed to this purpose as they allow us to render a reverberant sound field more efficiently by limiting its spatial resolution. The present study explores the perceptual impact of two simplifications of Ambisonics-based binaural reverberation that aim to improve efficiency. First, a “hybrid Ambisonics” approach is proposed in which the direct sound path is generated by convolution with a spatially dense head related impulse response set, separately from reverberation. Second, the reverberant virtual loudspeaker method (RVL) is presented as a computationally efficient approach to dynamically render binaural reverberation for multiple sources with the potential limitation of inaccurately simulatin...

2015

This contribution reviews the basics of Ambisonics and outlines examples of applied Ambisonics using microphone and loudspeaker arrays, and headphone-based rendering. Recent achievements will be addressed in Ambisonic software, panning and decoding, and the observation and optimizing of perceptual properties. Moreover, another highly topical field of higher-order Ambisonic recording is discussed, its fundamental spatial resolution versus SNR and bandwidth problem, a new filtering approach, and spatial mastering effects.

Proc. of the …, 2004

reproduction

Convincing sound reproduction via headphones requires filtering of virtual sound sources with head related transfer functions (HRTF). HRTFs describe signal differences at the two ear drums in level, time and frequency weighting [1,2]. Another psychoacoustic phenomenon of the ...

2005

A computationally efficient 3D real time rendering engine for binaural sound reproduction via headphones is presented. Binaural sound reproduction requires to filter the virtual sound source signals with head related transfer functions (HRTFs). To improve humans localization capabilities head tracking as well as room simulation have to be incorporated. This yields the problem of high-quality, time-varying interpolation between different HRTFs. To overcome this problem a virtual ambisonic approach is used that results in a bank of time-invariant HRTF filter.

2017

Last year Google enabled spatial audio in head-tracked 360 videos using Ambisonics to binaural decoding on Android mobile devices. There was some early criticism of the 1st order to binaural conversion employed by Google, in terms of the quality of localisation and noticeable frequency response colouration. In this paper, the algorithm used by Google is discussed and the Ambisonics to Binaural conversion using virtual speakers analysed with respect to the resulting inter-aural time, level, and spectrum differences compared to an example HRTF data set. 1st to 35th order Ambisonics using multiple virtual speaker arrays are implemented and analysed with inverse filtering techniques for smoothing the frequency spectrum also discussed demonstrating 8th order decoding correctly reproducing binaural cues up to 4 kHz.

H. Meller/F. Daim (eds.), Crosing boundaries - Mounted nomads in Central Europe, their eastern roots and connections. 14th Archaeological Conferecne of central Germany, October 2021 in Halle (Saale), 2022

The article gives an overview of the evidence for mounted nomads between the northern Caucasus and Central Europe in the early first millennium BCE before the Scythian impact around 600 BCE. It discusses the recent evidence of the genesis of the phenomenon of mounted nomads in Eurasia, touching on genetic as well as osteological findings regarding the use of horses as traction or riding animals, which represents a second stage in the domestication of the horse. The second part of the article discusses how the introduction of technological innovations regarding horse gear and bridling techniques that were developed by early mounted nomads originating in central Asia and Eastern Europe transformed items of the material culture and forms of status representation of communities west of the bend of the Danube. Based on selected examples from the northern Caucasus, the North Pontic steppe belt, and the Carpathian Basin, it touches on the historical dimension of a new way of horse bound warfare and a pastoral economy for the Early Iron Age cultures between the Carpathian Mountains and Central Europe.

Herramientas de Gestión Administrativas, 2019

Nuestro modelo de gestión escolar está enmarcado en preparar estudiantes competentes, aplicando estrategias de educación inclusiva diversificada, con empoderamiento de la problemática institucional, fortaleciendo el trabajo colaborativo, concientizando el cuidado y protección del medio ambiente que apoyen al mejoramiento de la calidad educativa. El departamento de rectorado y el equipo directivo, con el propósito de apoyar al mejoramiento de la calidad educativa institucional sobre la base de los resultados académicos de los últimos años, está emprendiendo en la construcción de herramientas de gestión administrativas y docentes que sean los pilares fundamentales que sustenten un mejoramiento académico según el contexto local de los estudiantes para reducir el bajo rendimiento de los alumnos, mejorar el comportamiento y re-establecer la convivencia armónica que se ve fragmentada por la falta de empoderamiento de quienes conformamos la Comunidad Educativa Marianista, es por ello que se presenta un consolidado de herramientas de gestión: Proyecto Educativo Institucional aprobado por el Distrito Educativo 10D01 el 08 de mayo del 2019, la Planificación Curricular Institucional valorada por los Asesores Educativos en el año 2018, el Manual de Procesos Administrativos socializado a la Comunidad Educativa en el año 2018 dentro del cual se incorpora el modelo de gestión institucional, el Manual de Procedimientos Académicos con los cuales se operativiza el Currículo Nacional 2016, Currículo Institucional propuesto en la Planificación Curricular Institucional, El Código de Convivencia Escolar registrado en el Distrito Educativo 10D01 en el año lectivo 2018-2019, Propuestas de mejoramiento administrativo y académico con los cuales la Unidad Educativa “Mariano Suárez Veintimilla” desde todas sus dependencias debe promover un cambio de actitud y ser partícipes de la aplicación adecuada de la normativa legal educativa vigente para emprender hacia la mejora continua institucional, con equidad, solidaridad, igualdad, fomentando una cultura de protección y cuidado del medio ambiente. Mgs. Leonardo Flores, Junio 2019