145th AES CONVENTION Engineering Brief Details

AES New York 2018
Engineering Brief Details

EB01 - Posters: Spatial Audio

Wednesday, October 17, 3:00 pm — 4:30 pm (Poster Area)

EB01-1 A Head-Related Transfer Function Database Consolidation Tool for High Variance Machine Learning AlgorithmsBenjamin Tsui, University of York - York, UK; Gavin Kearney, University of York - York, UK
Binaural based machine learning applications generally require a large number of HRTF (Head-Related Transfer Function) measurements. However, building an HRTF database from measurements of a large number of participants can be a time-consuming and tedious process. An alternative method is to combine the data from different existing databases to create a large training dataset. This is a significant challenge due to the large difference in measurement angles, filter size, normalization schemes, and sample rates inherent in different databases. Consequently, training of some machine learning algorithms can be cumbersome, requiring significant trial and error with different data and settings. To facilitate convenient preparation of datasets, this paper presents a Matlab-based tool that allows researchers to prepare and consolidate various HRTF datasets across different databases in a robust and fast manner. The tool is available online: https://github.com/Benjamin-Tsui/HRTF_preprocessing
Engineering Brief 451 (Download now)

EB01-2 SoundFields: A Mixed Reality Spatial Audio Game for Children with Autism Spectrum DisorderDaniel Johnston, University of York - York, UK; Hauke Egermann, University of York - York, UK; Gavin Kearney, University of York - York, UK
SoundFields is an interactive mixed reality experience developed for children with Autism Spectrum Disorders (ASD). The project aims to provide a technical intervention framework that has the potential to promote the improvement of joint attention, social interaction, and cognitive development through full-body interaction with virtual spatitalized auditory events. The SoundFields system is based in a 360-degree visual environment in which players can move freely around without the need for head mounted displays. By means of optical motion tracking, 3rd order ambisonic audio is transmitted wirelessly to headphones, reacting to head rotation and their position within the physical space.
Engineering Brief 452 (Download now)

EB01-3 Studio for Immersive Media Research and Production: Immersive Audio Lab at HAW HamburgPhilipp Kessling, HAW Hamburg, - Hamburg, Germany; Thomas Görne, Hamburg University of Applied Sciences - Hamburg, Germany
Spatial audio is becoming increasingly important in media production since the availability of adequate distribution channels and budget hardware for production and consumer side playback is increasing likewise. To not only provide a studio for the production of spatial audio content, but also accommodate research on immersive media, a novel facility has been implemented at Hamburg University of Applied Sciences (HAW). The “Immersive Audio Lab” comprises a 33.2 High Density Loudspeaker Array (HDLA) suitable for a diverse set of spatial audio coding formats including HOA, complemented with VR technology and a broadband tracking system.
Engineering Brief 453 (Download now)

EB01-4 Evaluation of Binaural Renderers in Virtual Reality Environments: Platform and ExamplesThomas Robotham, International Audio Laboratories Erlangen - Erlangen, Germany; Olli Rummukainen, Fraunhofer IIS - Erlangen, Germany; Jürgen Herre, International Audio Laboratories Erlangen - Erlangen, Germany; Fraunhofer IIS - Erlangen, Germany; Emanuël A. P. Habets, International Audio Laboratories Erlangen - Erlangen, Germany
One of the challenges of virtual reality technology is to provide convincing sensory information to users, to give the illusion of presence within the virtual environment. Audio-visual input combined with self-motion is a step beyond traditional cinematic content, whereby the audio renderer must accommodate a limitless number of potential user interactions and movements within an acoustic ?eld. In this e-Brief a framework for an online (real-time) 6 degrees-of-freedom evaluation platform is detailed. The platform allows psychoacoustic research and subjective testing of binaural audio renderers for virtual reality applications and ?nds application in the development of the MPEG-I Audio Standard.
Engineering Brief 454 (Download now)

EB01-5 Rapid HRTF Measurement in a Loudspeaker DomeNoé Philip Chevalier, HAW Hamburg - Hamburg, Germany; Piotr Majdak, Austrian Academy of Sciences - Vienna, Austria; Eva Wilk, University of Applied Sciences, Hamburg - Hamburg, Germany; Thomas Görne, Hamburg University of Applied Sciences - Hamburg, Germany
Spatial audio implementations with binaural playback benefit from personalized HRTF sets. Thus access to an efficient procedure for capturing individual Head Related Transfer Functions (HRTF) is beneficial for media production as well as for research and development in the ?eld. In the newly established Immersive Audio Lab at Hamburg University of Applied Sciences we implemented a fast HRTF measurement procedure in a 33-channel loudspeaker dome, utilizing the Multiple Exponential Sweep Method (MESM) introduced by Majdak, Balazs, and Laback [1]. One measurement of about 4 minutes results in a set of 289 discrete HRIRs, covering 360° in the horizontal plane and roughly -15°...90° elevation.
Engineering Brief 455 (Download now)

EB01-6 Survey of Media Device Ownership, Media Service Usage, and Group Media Consumption in UK HouseholdsCraig Cieciura, University of Surrey - Guildford, Surrey, UK; Russell Mason, University of Surrey - Guildford, Surrey, UK; Philip Coleman, University of Surrey - Guildford, Surrey, UK; Matthew Paradis, BBC Research and Development - London, UK
Homes contain a plethora of devices for audio-visual content consumption, which intelligent reproduction systems can exploit to give the best possible experience. To investigate media device ownership in the home, media service-types usage and solitary versus group audio/audio-visual media consumption, a survey of UK households with 1102 respondents was undertaken. The results suggest that there is already significant ownership of wireless and smart loudspeakers, as well as other interconnected devices containing loudspeakers such as smartphones and tablets. Questions on group media consumption suggest that the majority of listeners spend more time consuming media with others than alone, demonstrating an opportunity for systems that can adapt to varying audience requirements within the same environment.
Engineering Brief 456 (Download now)

EB01-7 A Perceptual Spectral Difference Model for Binaural SignalsCal Armstrong, University of York - York, UK; Thomas McKenzie, University of York - York, UK; Damian Murphy, University of York - York, UK; Gavin Kearney, University of York - York, UK
This paper presents a perception based model for calculating the difference between two binaural signals to more accurately represent the perceptual relevance of spectral differences. A basic spectral difference calculation, the difference between the fast Fourier transforms (FFTs) of two audio signals, is not an accurate metric for human perception as the auditory system differs greatly in sensitivity depending on relative amplitude, frequency, and temporal aspects. The presented model is evaluated through objective measures and comparison to the results of a previously published listening test.
Engineering Brief 457 (Download now)


EB02 - Live Sound, Recording, and Production

Friday, October 19, 9:00 am — 10:00 am (1E10)

Paul Geluso, New York University - New York, NY, USA

EB02-1 Loudness Metering in Sound Reinforcement: Utilities and Practical ConsiderationsCristian Eduardo Becerra Benítez, Universidad Tecnologica de Chile INACAP - Santiago de Chile, Chile; SABE Sonido
Loudness meters were created to standardize levels in broadcasting (radio and TV), to minimize differences between program level and commercial level. This standard is already used in several countries, but will it be useful for live sound? Will it allow for better mixing results in sound reinforcement situations? The following Engineering Brief aims to answer these questions and provide some considerations for loudness meters use in sound reinforcement.
Engineering Brief 458 (Download now)

EB02-2 Streamlined 3D Sound Design: The Capture and Composition of a Sound FieldWieslaw Woszczyk, McGill University - Montreal, QC, Canada; Paul Geluso, New York University - New York, NY, USA
A pragmatic approach to 3D sound design is described that employs a minimum number of sound fields captured with tetrahedral microphones. The captured sound fields, each extended in a horizontal and vertical dimension, are combined to provide the essential segments of the entire 360° sound design. Supplemental single-capsule microphones are used as needed for balancing of spaciousness and clarity. A compatible scaling of sound design from 3D to 2D can be easily accomplished without distortion of timbre or space.
Engineering Brief 459 (Download now)

EB02-3 Interactive Recorded Music: Past, Present, and FutureJustin Paterson, London College of Music, University of West London - London, UK; Rob Toulson, University of Westminster - London, UK
This Engineering Brief charts the story of user-interactivity with recorded music. Audio technologies and creative compositional techniques are discussed with particular regard to scenarios where creativity has driven the demand for technological advance, and vice-versa, where technical advance has enabled new creative-practice approaches. This is contextualized through discussion of relevant implementation in legacy systems, mobile applications, video games, artificial intelligence, and extended realities. In identifying seminal applications of music interactivity from the past and linking them to present capabilities and practices, future trajectories for interactive recorded-music are extrapolated.
Engineering Brief 460 (Download now)

EB02-4 Producing Audio Drama Content for an Array of Orchestrated Personal DevicesJon Francombe, BBC Research and Development - Salford, UK; James Woodcock, University of Salford - Salford, Greater Manchester, UK; Richard J. Hughes, University of Salford - Salford, Greater Manchester, UK; Kristian Hentschel, BBC Research and Development - Salford, UK; Eloise Whitmore, Naked Productions - Manchester, UK; Tony Churnside, Naked Productions - Manchester, UK
Personal devices with loudspeakers can be orchestrated to increase immersion from low channel count reproduction systems. A trial production was conducted to investigate the content creation work?ow and delivery mechanism for orchestrated devices. The content (a 13-minute science-?ction drama entitled “The Vostok-K Incident”) included: a stereo bed; elements only replayed from auxiliary devices; and elements that could either be in the stereo bed or replayed from auxiliary devices. A bespoke production environment was established, including plug-ins for authoring the metadata needed to utilize the rendering ruleset. Ambiguity in the reproduction system, coupled with ?exible and complex metadata authoring requirements, made the production challenging and time-consuming. Future work will focus on re?ning the production process and developing delivery tools.
Engineering Brief 461 (Download now)


EB03 - Posters: Recording and Production

Friday, October 19, 10:30 am — 12:00 pm (Poster Area)

EB03-1 Microphone Positions in Acoustic Field Reconstruction: Robustness Analysis and OptimizationYuchen Shen, Nanjing University - Nanjing, China; Ziyun Liu, Nanjing University - Nanjing, China; Yong Shen, Nanjing University - Nanjing, Jiangsu Province, China; Ning Xiang, Rensselaer Polytechnic Institute - Troy, NY, USA
This paper introduces a low-cost, simple structure, and high-convenience 3D microphone positioning system for scanning acoustic field of sound sources. For the inherent errors caused by motors, mechanical fluctuations, and string deformations this work describes an anti-error method based on experimentally measured data to eliminate the corresponding effect. The method can determine a weighting strategy for every measured data and could be extended to any scanning system.
Engineering Brief 462 (Download now)

EB03-2 Creating Object-Based Stimuli to Explore Media Device Orchestration Reproduction TechniquesCraig Cieciura, University of Surrey - Guildford, Surrey, UK; Russell Mason, University of Surrey - Guildford, Surrey, UK; Philip Coleman, University of Surrey - Guildford, Surrey, UK; Matthew Paradis, BBC Research and Development - London, UK
Media Device Orchestration (MDO) makes use of interconnected devices to augment a reproduction system, and could be used to deliver more immersive audio experiences to domestic audiences. To investigate optimal rendering on an MDO-based system, stimuli were created via: (1) object-based audio (OBA) mixes undertaken in a reference listening room; and (2) up to 13 rendered versions of these employing a range of installed and ad-hoc loudspeakers with varying cost, quality, and position. The program items include audio-visual material (short ?lm trailer and big band performance) and audio-only material (radio panel show, pop track, football match, and orchestral performance). The object-based program items and alternate MDO con?gurations are made available for testing and demonstrating OBA systems.
Engineering Brief 463 (Download now)

EB03-3 Practical Recording Techniques for Music Production with Six-Degrees of Freedom Virtual RealityDavid Rivas Méndez, University of York - York, UK; Cal Armstrong, University of York - York, UK; Jessica Stubbs, University of York - York, UK; Mirek Stiles, Abbey Road Studios - London, UK; Gavin Kearney, University of York - York, UK
This paper presents practical spatial audio recording techniques for capturing live music performances for reproduction in a six-degrees of freedom (6DOF) virtual reality (VR) framework. The end-goal is to give the listener the ability to move close to or even around musical sources with a high degree of plausibility to match the visuals. The recording workflow facilitates three major rendering schemes–object-based using spot microphones and diffuse field capture microphone arrays, Ambisonics with multiple-placed sound-field microphones, and hybrid approaches that utilize the prior two methods. The work is presented as a case-study where a jazz ensemble is recorded at Studio 3 of Abbey Road Studios London using the proposed techniques.
Engineering Brief 464 (Download now)

EB03-4 A DAW-Based Interactive Tool for Perceptual Spatial Audio EvaluationTomasz Rudzki, University of York - York, UK; Damian Murphy, University of York - York, UK; Gavin Kearney, University of York - York, UK
A software tool for subjective audio evaluation is presented. The tool helps to overcome the limits of the existing listening test tools by allowing DAW-based multichannel playback with required signal processing and enabling the use of novel test participant interfaces: mobile app, physical controller, and VR interface. Test preparation is done by importing audio samples into the spatial audio standard DAW and setting up the required signal processing plugins. The listening test tool triggers the playback of the desired audio samples inside the DAW, according to the participant’s choice. The tool described in this paper can be used for various perceptual audio tests, including evaluation of spatial audio codecs, virtual acoustics, and binaural rendering engines.
Engineering Brief 465 (Download now)

EB03-5 Stationary Music from Users’ Viewpoint in VR ApplicationsSungsoo Kim, New York University - New York, NY, USA; Sripathi Sridhar, New York University - New York, NY, USA
The ultimate goal in virtual reality (VR) is to achieve complete immersion in terms of audio and video, where background music is typically included to keep users absorbed in a game or 360-video content. This paper explores a multichannel loudspeaker configuration to anchor the background music to the user’s viewpoint in VR. To that end, an evenly-spaced octagonal loudspeaker configuration is implemented in order to anchor the background music using head tracking data. The real-time panning is achieved through Vector-Base Amplitude Panning (VBAP). This paper also describes a demo interface built using the Oculus Rift in Unity and Max/MSP, as proof of concept.
Engineering Brief 466 (Download now)

EB03-6 Implementation of 4-pi Reverberation Effects in Immersive Sound Contents—Balance of Object-Based Tracks and Channel-Based TracksAkiho Matsuo, SONA Co. - Tokyo-to, Japan; Ritsuko Tsuchikura, SONA Co. - Nakano-ku, Tokyo, Japan; Masumi Takino, be Blue Co . - Minato-ku, Tokyo, Japan; Masataka Nakahara, ONFUTURE Ltd. - Tokyo, Japan; SONA Corp. - Tokyo, Japan
The paper describes effective use of 4-pi (all directional) acoustical information of reverberation for post-production works. Measurement and analysis technique of sound intensities, VSV(Virtual Source Visualizer), is used for capturing 4-pi reverberations, and the obtained reverberations, VSVerb, are mapped on audio tracks of a DAW. In order to obtain precise rendering of spatial characteristics of the VSVerb, it is ideal to assign one object track to one reflection component. However, Dolby Atmos has the number of reflections restricted to 118. According to the hearing impressions by the authors show this restriction is impractical. This paper proposes a practical method to balance objects’ and beds’ tracks with less auditory deterioration.
Engineering Brief 467 (Download now)

EB03-7 Development of a 4-pi Sampling Reverberator, VSVerb—Source ReductionMasataka 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
The authors developed a 4-pi sampling reverberator, named “VSVerb,” which restores a 4-pi reverberant field by using information of dominant reflections that are captured in a target space. The timings and amplitudes of reflections are obtained from the analyses results of the sound intensities that are measured at the site in orthogonal three directions. The generated reverberation provides high S/N performance and enables to adjust various acoustic parameters with no additional measurements. These advantages provide the VSVerb with high affinity with post-production works. In order to enhance its affinity with object-based production schemes, this manuscript proposes a practical method to reduce a number of reflections from generated reverberations. The method, called “Source Reduction,” thins out reflections with less auditory deterioration.
Engineering Brief 468 (Download now)

EB03-8 In-Ear Headphone System with Piezoelectric MEMs DriverAndreas Männchen, Fraunhofer Institute for Digital Media Technology IDMT - Ilmenau, Germany; Fabian Stoppel, Fraunhofer Institute for Silicon Technology ISIT - Itzehoe, Germany; Daniel Beer, Fraunhofer Institute for Digital Media Technology IDMT - Ilmenau, Germany; Florian Niekiel, Fraunhofer Institute for Silicon Technology ISIT - Itzehoe, Germany; Bernhard Wagner, Fraunhofer Institute for Silicon Technology ISIT - Itzehoe, Germany
This article presents a prototype in-ear headphone system based on a previously disclosed piezoelectric MEMS driver technology (piezoMEMS). The centerpiece of the earphone is a 4 mm x 4 mm piezoMEMS chip loudspeaker that on its own achieves broadband sound pressure levels of up to 110 dB in an IEC 60318-4 ear simulator. A specifically designed enclosure allows for easy installation of the piezoMEMS driver and takes first steps in optimizing the acoustic performance. Furthermore, the system comprises a specially tailored amplifier as well as a dedicated signal processing concept. The article describes the ideas behind the system, discusses the particular challenges in designing the piezoMEMS earphone, shows measurement results, and, finally, discusses the vast opportunities for future research.
Engineering Brief 469 (Download now)


EB04 - Applications in Audio

Friday, October 19, 4:30 pm — 5:45 pm (1E11)

Ivan Bourmeyster, Arkamys - Paris, France

EB04-1 WithdrawnN/A

EB04-2 Description of the Single Note Database SNDBEsther Fee Feichtner, International Audio Laboratories Erlangen - Erlangen, Germany; Bernd Edler, International Audio Laboratories Erlangen - Erlangen, Germany
Big and well-tagged databases are needed for many tasks in music information retrieval. Therefore we created the single note database (SNDB) containing over 30,000 single notes of 11 orchestra instruments by extracting and combining material of well-established databases. The ground truth was manually checked, corrected, and augmented. The result is a large and easy to handle database providing a reliable ground truth with a high variety for each class. Because of well-known original databases, new scientific results can be easily compared to earlier approaches. Here we show the benefit of the SNDB in a simple example. Moreover, we depict how the SNDB was created in the first place and how it can be conveniently reproduced from the original databases.
Engineering Brief 471 (Download now)

EB04-3 Not PresentedN/A

EB04-4 Why Can You Hear a Difference between Pouring Hot and Cold Water? An Investigation of Temperature Dependence in PsychoacousticsHe Peng, University of California, San Diego - San Diego, CA, USA; Joshua D. Reiss, Queen Mary University of London - London, UK
Studies have shown that listeners can distinguish between hot and cold water being poured based solely on sonic properties, yet the cause of this is unknown. This acoustic perception of temperature is an interesting aspect of multisensory perception and integration. In this paper a series of experiments were performed to investigate the characteristics of auditory information when water is poured at different temperatures into various containers. Based on the results, it attempts to find physical and psychoacoustic explanations for the phenomenon.
Engineering Brief 473 (Download now)

EB04-5 Introduction to Acoustic Meshes in Audio ApplicationsJason McIntosh, SAATI, SPA - Appiano Gentile (C0), Italy
Acoustic applications utilize thin porous materials for a variety of reasons, the primary one being to provide an acoustic resistance. This resistance dampens acoustic modes, allowing the designer to control their behavior. However, to achieve consistent resistive damping requires a level of precision manufacturing not found in common materials. SAATI of Italy produces a broad range of specialty woven meshes for acoustic applications that achieve this precision through a highly controlled weaving process. Some understanding of the weaving process is helpful in guiding a designer’s choice of materials.
Engineering Brief 474 (Download now)

EB04-6 The Sound Diffusion Simulation Software Basing on Finite-Difference Time-Domain MethodKamil Piotrowski, AGH University of Science and Technology - Kraków, Poland; Adam Pilch, AGH University of Science and Technology - Krakow, Poland
The aim of the project was to create an application that allows users to simulate acoustic wave propagation according to given input parameters. The program was based on MATLAB environment and most parts of it were designed using k-Wave toolbox, the package operating on a finite-difference time-domain method calculations (FDTD). The application enables to create a heterogeneous medium and measure sound pressure distribution in a simulated scenario. Separate program module contains time and frequency analysis of obtained waveforms and gives the user a possibility to visualize the results. What is more, the software also computes directional diffusion coefficient d in accordance with ISO 17497-2:2012 of defined sound diffusers and makes one independent from complex measurements in an anechoic chamber.
Engineering Brief 10075 (Download now)


EB05 - Spatial Audio

Saturday, October 20, 9:00 am — 10:00 am (1E11)

Gavin Kearney, University of York - York, UK

EB05-1 Creative Approach to Audio in Corporate Brand ExperiencesAlexander Mayo, Arup - New York, NY, USA; Nathan Blum, Arup - New York, NY, USA; Leonard Roussel, Arup - New York, NY, USA
Corporate clients have become focused on turning their digital platforms into human experiences. As designers, we must create unique solutions that speak to the corporation's brand identity. For the Lobby at Salesforce New York, the Salesforce “Trailblazer” brand is brought to life through a sonic landscape. A spatial audio system and custom composition is paired with immersive lighting and LED displays to create a multimedia entry into Salesforce. This 3D sound system installation: • Reinforces the Salesforce brand and is inspired by their events; • Employs multiple loudspeakers, network audio transport, and integrated control; • Makes use of audio samples arranged in a composition which utilizes an object-based spatialization engine; •Integrates seamlessly with architectural features and building systems.
Engineering Brief 475 (Download now)

EB05-2 Subspace-Based HRTF Synthesis from Sparse Data: A Joint PCA and ML-Based ApproachSunil G. Bharitkar, HP Labs., Inc. - San Francisco, CA, USA; Timothy Mauer, HP, Inc. - Vancouver, WA, USA; Teresa Wells, HP, Inc. - San Francisco, CA, USA; David Berfanger, HP, Inc. - Vancouver, WA, USA
Head-related transfer functions (HRTF) are used for creating the perception of a virtual sound source at an arbitrary azimuth-elevation. Publicly available databases use a subset of these directions due to physical constraints (viz., loudspeakers for generating the stimuli not being point-sources) and the time required to acquire and deconvolve responses for a large number of spatial directions. In this paper we present a subspace-based technique for reconstructing HRTFs at arbitrary directions for the IRCAM-Listen HRTF database, which comprises a set of HRTFs sampled every 15 deg along the azimuth direction. The presented technique includes first augmenting the sparse IRCAM dataset using the concept of auditory localization blur, then deriving a set of P=6 principal components, using PCA for the original and augmented HRTFs, and then training a neural network (ANN) with these directional principal components. The reconstruction of HRTF corresponding to an arbitrary direction is achieved by post-multiplying the ANN output, comprising the estimated six principal components, with a frequency weighting matrix. The advantage of using a subspace approach, involving only 6 principal components, is to obtain a low complexity HRTF synthesis ANN-based model as compared to training an ANN model to output an HRTF over all frequencies. Objective results demonstrate a reasonable interpolation with the presented approach.
Engineering Brief 476 (Download now)

EB05-3 Audio Application Programming Interface for Mixed RealityRémi Audfray, Magic Leap, Inc. - San Francisco, CA, USA; Jean-Marc Jot, Magic Leap - San Francisco, CA, USA; Sam Dicker, Magic Leap, Inc. - San Francisco, CA, USA
In mixed reality (MR) applications, digital audio objects are rendered via an acoustically transparent playback system to blend with the physical surroundings of the listener. This requires a binaural simulation process that perceptually matches the reverberation properties of the local environment, so that virtual sounds are not distinguishable from real sounds emitted around the listener. In this paper we propose an acoustic scene programming model that allows pre-authoring the behaviors and trajectories of a set of sound sources in a MR audio experience, while deferring to rendering time the specification of the reverberation properties of the enclosing room.
Engineering Brief 477 (Download now)

EB05-4 Accessible Object-Based Audio Using Hierarchical Narrative Importance MetadataLauren Ward, University of Salford - Salford, UK; Ben Shirley, University of Salford - Salford, Greater Manchester, UK; Salsa Sound Ltd - Salford, Greater Manchester, UK; Jon Francombe, BBC Research and Development - Salford, UK
Object-based audio has great capacity for production and delivery of adaptive and personalizable content. This can be used to improve the accessibility of complex content for listeners with hearing impairments. An adaptive object-based audio system was used to make mix changes enabling listeners to balance narrative comprehension against immersion using a single dial. Performance was evaluated by focus groups of 12 hearing impaired participants who gave primarily positive feedback. An experienced sound designer also evaluated the function of the control and process for authoring the necessary metadata establishing that the control facilitated a clearer narrative while maintaining mix quality. In future work the algorithm, production tools, and interface will be refined based on the feedback received.
Engineering Brief 478 (Download now)


EB06 - Transducers

Saturday, October 20, 10:15 am — 11:15 am (1E11)

Masataka Nakahara, ONFUTURE Ltd. - Tokyo, Japan; SONA Corp. - Tokyo, Japan

EB06-1 A Dante Powered Modular Microphone Array SystemMirco Pezzoli, Politecnico di Milano - Milan, Italy; Luca Comanducci, Politecnico di Milano - Milan, Italy; Joe Waltz, Eventide - Little Ferry, NJ, USA; Anthony Agnello, Eventide Inc. - Little Ferry, NJ, USA; Luca Bondi, Politecnico di Milano - Milano, IT; Antonio Canclini, Politecnico di Milano - Milan, Italy; Augusto Sarti, Politecnico di Milano - Milan, Italy
Eventide Inc. and Politecnico di Milano are collaborating to present a versatile high-performance Network Based Modular Microphone Array System (MMAS). One advantage of the system is the ability to quickly build various linear and planar array geometries with up to 64 microphone elements (sensors) connected to a single workstation, with the option to expand up to 512 sensors by synchronizing multiple sub-systems. The system modules (eStick) consist of a 48cm linear array made of 16 MEMS microphones with an integrated Audinate Dante Power-over-Ethernet (PoE) interface. The system is intended to support a wide range of industrial and research applications, ranging from advanced sound scene analysis and manipulation to source separation, extraction, and tracking.
Engineering Brief 479 (Download now)

EB06-2 Low-Complexity Non-Linear Loudspeaker ProtectionDaniil Sinev, ARKAMYS - Paris, France; Le Mans University - Le Mans, France
These days high-end loudspeakers are not seen with as much reverence as before, and the market is becoming dominated by their cheaper, more efficient counterparts. At the same time the demand for higher sound pressure levels is growing, which creates audible distortion problems. There are various DSP solutions for this, from tried-and-true fixed high pass filter, which, while getting rid of distortion, also cuts out a lot of bass frequencies, to complex new solutions based on physical models and adaptive signal processing. This paper proposes an approach that improves on the former while staying much less demanding than the latter in terms of computational power.
Engineering Brief 480 (Download now)

EB06-3 No PresentationN/A

Engineering Brief 481 (Download now)

EB06-4 Influence of Horn’s Surface Temperature on its Directivity ControlDave "Rat" Levine, Rat Sound Systems - Camarillo, CA, USA; Paolo Calza, Contralto Audio srl - Parma, Italy; Mario Di Cola, Contralto Audio srl - Parma, Italy; Paolo Martignon, Contralto Audio srl - Parma (PR), Italy; Letizia Chisari, Contralto Audio srl - Milan, Italy
Horn directivity control and dispersion angles, especially at high frequency, have always been achieved by carefully design and optimized the horn’s surface. It can be experimentally demonstrated that the control properties of constant directivity, high-frequency horns may be influenced by the horn’s surface temperature which can be severely affected, for instance, by being exposed to direct sunlight. This e-brief presentation shows various experimental results that demonstrates the phenomenon and shows how much this problem can influence the directivity control at high frequency range.
Engineering Brief 482 (Download now)


EB07 - Posters: Applications in Audio

Saturday, October 20, 2:30 pm — 4:00 pm (Poster Area)

EB07-1 Noise Reduction for Randomized Speech and Audio Coding in WASNsJohannes Fischer, International Audio Laboratories Erlangen - Erlangen, Germany; Tom Bäckström, Aalto University - Espoo, Finland
We are surrounded by a multitude of connected devices with microphones, the signal of which should be combined for best sound quality. Thus, we recently proposed a distributed speech and audio codec that decorrelates quantization noise applying randomization. In this paper this method is extended attenuating quantization noise using Wiener filtering at the decoder. We demonstrate that this approach can be used to jointly attenuate quantization noise and background noise present at the microphones. By using orthogonal randomization matrices, computational complexity can be minimized by separating the Wiener ?lter from the inverse randomization. Our evaluation shows that Wiener filtering in combination with a randomized distributed codec is an efficient method to attenuate background and quantization noise at the decoder.
Engineering Brief 483 (Download now)

EB07-2 Adaptive Ballistics Control of Dynamic Range Compression for Percussive TracksDave Moffat, Queen Mary University London - London, UK; Mark Sandler, Queen Mary University of London - London, UK
Dynamic range compression (DRC) is a very commonly used audio effect. One use of DRC is to emphasize transients in an audio signal. The aim of this paper is to present an approach for automatically setting dynamic range compression timing parameters, adaptively, allowing parameters to adapt to the incoming audio signal, with the aim of emphasizing transients within percussive audio tracks. An implementation approach is presented.
Engineering Brief 484 (Download now)

EB07-3 A Device for Measuring Auditory Brainstem Responses to AudioPiotr Odya, Gdansk University of Technology - Gdansk, Poland; Andrzej Czyzewski, Gdansk University of Technology - Gdansk, Poland; Andrzej Sroczynski, Gdansk University of Technology - Gdansk, Poland; Bozena Kostek, Gdansk University of Technology - Gdansk, Poland; Audio Acoustics Lab.
Standard ABR devices use clicks and tone bursts to assess subjects’ hearing in an objective way. A new device was developed that extends the functionality of a standard ABR audiometer by collecting and analyzing auditory brainstem responses (ABR). The developed accessory allows for the use of complex sounds (e.g., speech or music excerpts) as stimuli. Therefore, it is possible to find out how efficiently different types of sounds are processed in the hearing system including brain. The paper contains technical details related to the design of the device, including its hardware and software parts. The test results that have been carried out to verify the operation of the device are also described.
Engineering Brief 485 (Download now)

EB07-4 Measuring and Evaluating Excess Noise in ResistorsBrewster LaMacchia, Clockworks Signal Processing LLC - Andover, MA, USA; Bradford Swanson, Tufts University - Cambridge, MA
All resistors generate white (Johnson-Nysquist) noise based on their value and temperature; they can also generate several other types of (excess) noise. The amount or characteristics of a resistor’s excess noise could be one factor contributing to variations in perceived sound quality. This research explores methods for measuring the Johnson-Nysquist and excess noise of different resistors with the hopes of quantifying the performance of the components under test. A methodology is proposed for evaluating the audibility of both Johnson-Nysquist and excess noise that requires no special measurement equipment, only a sound system with suitable computer and freely available software.
Engineering Brief 486 (Download now)

EB07-5 A New Compact 3D Reproduction System: The Tetra-SpeakerParichat Songmuang, New York University - New York, NY, USA
As 3D audio becomes a prominent field of research in audio technology, researchers continue to develop reproduction methods that will best translate 3D recordings. Reproduction techniques have ranged from unique surround systems to 3D speakers such as the dodecahedron. However, these methods may be complex with its disadvantages. These systems tend to be configured for ambient or surround recordings. In this recent project, a new 3D speaker system was created not only for those surround recordings but also for individual sources. The speaker takes influence from the tetra-microphone structure. Testing for the radiation pattern has yet to be conducted. This project is an ongoing research and explores its use with different single-source recordings as well as creative “moving” audio.
Engineering Brief 487 (Download now)

EB07-6 Music Streaming Platforms—Quality and Technical ComparisonPawel Malecki, AGH University of Science and Technology - Krakow, Poland; Dorota Czopek, AGH University of Science and Technology - Krakow, Poland; Katarzyna Sochaczewska, AGH University of Science and Technology - Krakow, Poland
Music streaming platforms dominate the contemporary music industry. Through such platforms for a fixed monthly fee, or even for free, listeners get access to a huge online music database. In recent years many platforms have been created and they currently compete with each other. They offer different subscription prices, sound quality, and service ranges. This paper presents a comparison of the technical parameters and an auditory assessment of the differences between selected streaming platforms. A listening test containing diversified sound material was carried out using the ABX method (3IFC - 3 interval stimulus with forced choice and hidden reference). Over 50 subjects participated in the listening test. After basic statistical analysis, the results were presented in graphical form.
Engineering Brief 488 (Download now)

EB07-7 Development of Ambisonic Microphone Design Tools—Part 1Charles Middlicott, University of Derby - Derby, UK; Bruce Wiggins, University of Derby - Derby, Derbyshire, UK
In recent years an increase in the capture and production of ambisonic material has occurred as a result of companies such as YouTube and Facebook utilizing ambisonics for spatial audio playback. There is now a greater need for affordable higher order microphone arrays. This work details the development of a set of tools that can be used to simulate and evaluate such microphone arrays, The “Ambisonic Array Design Tool” for simulation and “Ambisonic Array Evaluation Tool” for evaluation. The microphone capsules’ position and directivity can be changed, with the effects on the synthesized spherical harmonics frequency and polar responses observed within the GUI. These scripts written in MatLab have been packaged within a GUI and will be available online.
Engineering Brief 489 (Download now)

EB07-8 Introducing a Dataset of Guitar Amplifier Sounds for Nonlinear Emulation BenchmarkingThomas Schmitz, University of Liege - Liege, Belgium; Jean-Jacques Embrechts, University of Liege - Liege, Belgium
Recent progresses made in the nonlinear system identification field have improved the ability to emulate nonlinear audio systems such as tube guitar amplifiers. As a straightforward comparison of different models cannot always be made, we propose a new reference dataset enabling to highlight the strengths and weaknesses of different nonlinear modeling methods. Our dataset gathers five different styles of guitar sounds passing through different guitar amplifiers with 10 steps of their gain parameter (i.e., the distortion level of the amplifier). Moreover, a Matlab function is also provided to obtain the desired input/output sounds in a matrix form.
Engineering Brief 490 (Download now)


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