AES New York 2017
Engineering Brief EB01
EB01 - Posters—Part 1
Wednesday, October 18, 2:15 pm — 3:45 pm (Poster Area)
EB01-1 Frontal Sound Localization with Headphone Systems Using Characteristics of Each Device—Yuya Ono, University of Aizu - Aizu Wakamatsu, Japan; Akira Saji, University of Aizu - Aizuwakamatsu City, Japan; Jie Huang, University of Aizu - Aizuwakamatsu City, Japan
Generally, it is difficult to localize sounds on frontal positions with headphones because of the so called in-the-head localization. In this paper we proposed a method to create sound images on frontal positions by cancelling the frequency characteristics of sounds from headphones and adapting the frequency characteristics of sounds from frontal loudspeaker that are measured with HATS. We held auditory experiments that evaluating the similarity and naturalness between the sounds from frontal loudspeaker and headphones on the participants. As a result, we found the method can decrease the in-the-head localization
Engineering Brief 354 (Download now)
EB01-2 Design of Loudspeaker Crossover Networks Using Genetic Algorithm—Christian Claumarch, Aalborg University - Aalborg, Denmark; Kasper Kiis Jensen, Aalborg University - Aalborg, Denmark; Mikkel Krogh Simonsen, Aalborg University - Aalborg, Denmark
This brief proposes a method which allows for automation of the design of crossover networks for loudspeakers. The algorithm utilizes a combination of Genetic Algorithm and Least Squared Error Frequency Domain Design to find optimal type 1 FIR-filters fitting a target. The algorithm takes magnitude response, group delay, directivity index and displacement into account. Based on a two-way loudspeaker, the algorithm is capable of finding a crossover network which results in the final loudspeaker having a flat magnitude response from 105 Hz– 16 kHz ± 1.6 dB on-axis, where the directivity index is minimized and displacement limits are not exceeded
Engineering Brief 355 (Download now)
EB01-3 Microphone Array Impulse Response (MAIR) Library for Spatial Audio Research—Hyunkook Lee, University of Huddersfield - Huddersfield, UK; Connor Millns, University of Huddersfield - Huddersfield, UK
This engineering brief describes an open-access library of an extensive set of room impulse responses (RIRs) captured using numerous microphone arrays from 2-channel stereo to 9-channel surround with height. The RIRs were obtained for 13 loudspeakers placed in various positions on a stage in a reverberant concert hall. The library features five 2-channel stereo pairs, 10 main surround arrays, nine height microphone arrays for 3D main arrays and 15 4-channel configurations for surround and 3D ambience arrays, each with varied microphone polar patterns, directions, spacings, and heights. A dummy head and a first-order-Ambisonics microphone are also included. The library is provided with a rendering tool, with which the user can easily simulate different microphone combinations in both loudspeaker and binaural playback for 13 source positions. The library can be freely downloaded from the Resources section of the APL website: https://www.hud.ac.uk/apl
Engineering Brief 356 (Download now)
EB01-4 A Database of Head-Related Transfer Functions and Morphological Measurements—Rahulram Sridhar, Princeton University - Princeton, NJ, USA; Joseph G. Tylka, Princeton University - Princeton, NJ, USA; Edgar Choueiri, Princeton University - Princeton, NJ, USA
A database of head-related transfer function (HRTF) and morphological measurements of human subjects and mannequins is presented. Data-driven HRTF estimation techniques require large datasets of measured HRTFs and morphological data, but only a few such databases are freely available. This paper describes an on-going project to measure HRTFs and corresponding 3D morphological scans. For a given subject, 648 HRTFs are measured at a distance of 0.76 m in an anechoic chamber and 3D scans of the subject’s head and upper torso are acquired using structured-light scanners. The HRTF data are stored in the standardized “SOFA format” (spatially-oriented format for acoustics) while scans are stored in the Polygon File Format. The database is freely available online.
Engineering Brief 357 (Download now)
EB01-5 Phase Continuity in Amplitude-Phase Spatial Audio Coding—François Becker, Coronal Audio - Paris, France; Benjamin Bernard, Coronal Audio - Monaco, Monaco; Longcat Audio Technologies - Chalon-sur-Saone, France; Clément Carron, Coronal Audio - Lyon, France; Longcat Audio
In the context of amplitude-phase spatial audio coding, we give a proof of a phase discontinuity problem that affects all previous tridimensional stereo-compatible schemes. We solve it by using a dynamic mapping of spherical coordinates to the Scheiber sphere, which ensures phase continuity.
Engineering Brief 358 (Download now)
EB01-6 Evaluation of Binaural Renderers: A Methodology—Gregory Reardon, New York University - New York, NY, USA; Agnieszka Roginska, New York University - New York, NY, USA; Patrick Flanagan, THX Ltd. - San Francisco, CA, USA; Juan Simon Calle, New York University - New York, NY, USA; THX; Andrea Genovese, New York University - New York, NY, USA; Gabriel Zalles, New York University - New York, NY, USA; Marta Olko, New York University - New York, NY, USA; Christal Jerez, New York University - New York, NY, USA; Platinum Sound Recording Studio
Recent developments in immersive audio technology have motivated a proliferation of binaural renderers used for creating spatial audio content. Binaural renderers leverage psychoacoustic features of human hearing to reproduce a 3D sound image over headphones. In this paper a methodology for the comparative evaluation of different binaural renderers is presented. The methodological approach is threefold. A subjective evaluation of 1) quantitative characteristics (such as front/back and up/down discrimination, localization) ; 2) qualitative characteristics (such as timbre, naturalness); and 3) overall preference. The main objective of the methodology is to help to elucidate the most meaningful factors for the performance of binaural renderers and to provide indications on possible improvements in the rendering process.
Engineering Brief 359 (Download now)
EB01-7 Simultaneous HRTF Measurement of Multiple Source Configurations Utilizing Semi-Permanent Structural Mounts—Cal Armstrong, University of York - York, UK; Andrew Chadwick, University of York - York, UK; Lewis Thresh, University of York - York, UK; Damian Murphy, University of York - York, UK; Gavin Kearney, University of York - York, UK
A compact HRTF measurement rig has been designed and erected within the anechoic chamber at AudioLab, University of York. Utilizing 24 discrete elevations the efficient simultaneous HRTF measurement of 11 popular source configurations, ideally suited for the binaural rendering of Ambisonics, is undertaken. An overlapped exponential swept sine technique is used to make optimal use of a subject’s time. This report details the practical requirements, technical workflow and processing involved in the HRTF measurements, for inclusion to the SADIE database. The necessary modelling of low frequency cues is discussed.
Engineering Brief 360 (Download now)
EB01-8 Influence of Audience Noises on the Classical Music Perception on the Example of Anti-cough Candies Unwrapping Noise—Adam Pilch, AGH University of Science and Technology - Krakow, Poland; Bartlomiej Chojnacki, AGH University of Science and Technology - Kracow, Poland; Teresa Makuch, AGH University of Science and Technology - Cracow, Poland; Zuzanna Kusal, AGH University of Science and Technology - Kracow, Poland; Marcjanna Czapla, AGH University of Science and Technology - Kracow, Poland
A common problem in concert halls are people in the audience who distract other listeners by creating noises. Unwrapping anti-cough candies is an example of such undesirable behavior. The subject of the paper is to compare and analyze acoustic parameters of various candy wrappings in order to determine the discomfort they cause. The sounds generated while removing wrappings made of different materials were recorded in an anechoic chamber. The recordings were then analyzed in order to locate sounds in the audible frequency band in relation to musical sounds. Based on the results and a survey that was also carried out, an attempt was made to specify parameters of the noises perceived as most distracting.
Engineering Brief 361 (Download now)
EB01-9 A Simple Evaluating Method of a Reproduced Sound Field by a Measurement of Sound Intensities Using Virtual Source Visualizer—Masataka Nakahara, ONFUTURE Ltd. - Tokyo, Japan; SONA Corp. - Tokyo, Japan; Akira Omoto, Kyushu University - Fukuoka, Japan; Onfuture Ltd. - Tokyo, Japan; Yasuhiko Nagatomo, Evixar Inc. - Tokyo, Japan
Recently, many kinds of technologies for restoring/reproducing 3D sound fields are proposed. However, it is little opportunity to compare these acoustic performances under a common condition. Though a subjective evaluation is one of the most effective methods for evaluating reproduced sound fields, it requires careful effort. Therefore, the authors propose an alternative method which requires only a physical measurement of sound intensities. Because the method is based on the intensity analysis, “sound images” are assumed to be “amplitude-based phantom sound sources” here. In order to verify effectiveness of the method, various types of reproduced fields were measured and analyzed. As a result, it is ascertained that the method can evaluate proper features of reproduced sound fields, regardless of their restoring techniques.
Engineering Brief 362 (Download now)
EB01-10 Physical Evaluations of Reproduced Sound Fields by a Measurements of Sound Intensities Using Virtual Source Visualizer—Takashi Mikami, SONA Co. - Tokyo, Japan; Masataka Nakahara, ONFUTURE Ltd. - Tokyo, Japan; SONA Corp. - Tokyo, Japan; Akira Omoto, Kyushu University - Fukuoka, Japan; Onfuture Ltd. - Tokyo, Japan
In order to evaluate acoustic properties of reproduced sound fields, sound intensities were measured and analyzed in various types of multichannel studios by using a Virtual Source Visualizer (VSV hereafter). First, two different methods to reproduce sound fields are examined; 24ch amplitude-based phantom sound sources and Kirchhoff-Helmholtz-integral-based Boundary Surface Control principle. Secondly, sound fields created by four different types of 3D panners are examined; Dolby Atmos, DTS:X, Auro-3D and 22.2ch. Through these measurements, it was demonstrated that the VSV analyzes acoustic features of reproduced fields well, and interchangeabilities and differences of acoustic properties among different reproduced fields can be understood clearly. The session discusses accuracy and features of various types of reproduced sound fields which we measured and analyzed by the VSV.
Engineering Brief 363 (Download now)
Engineering Brief 382 (Download now)