AES New York 2018
Poster Session P11
P11 - Applications in Audio
Thursday, October 18, 2:45 pm — 4:15 pm (Poster Area)
P11-1 Optimal Exciter Array Placement for Flat-Panel Loudspeakers Based on a Single-Mode, Parallel-Drive Layout—David Anderson, University of Pittsburgh - Pittsburgh, PA, USA; Michael Heilemann, University of Rochester - Rochester, NY, USA; Mark F. Bocko, University of Rochester - Rochester, NY, USA
Flat-Panel Loudspeakers are most effective at reproducing audio non-directionally when operating at frequencies with many overlapping modes. Frequency regions with low modal overlap produce directional acoustic radiation, long decay times, as well as sharp peaks and notches in pressure. Exciter arrays re-enable use of these frequency regions by restricting structural excitation to a single mode until the frequency region of high modal overlap. An optimization method is described here for determining the placement of exciters such that they are all driven by a single amplifier yet only excite a single structural mode. Experimental results are reported for an acrylic panel with 4, 8, and 11 exciters that demonstrate successful operation of the exciter arrangements.
Convention Paper 10084 (Purchase now)
P11-2 Solar Powered Autonomous Node for Wireless Acoustic Sensor Networks Based on ARM Cortex M4—Alfredo Fernández-Toloba, University of Alcalá - Alcalá de Henares, Madrid, Spain; Héctor A. Sánchez-Hevia, University of Alcalá - Alcalá de Henares, Madrid, Spain; Rubén Espino-Sanjosé, University of Alcalá - Alcalá de Henares, Madrid, Spain; César Clares-Crespo, University of Alcalá - Alcalá de Henares, Madrid, Spain; Joaquín García-Gómez, University of Alcalá - Alcalá de Henares, Madrid, Spain; Roberto Gil-Pita, University of Alcalá - Alcalá de Henares, Madrid, Spain
The project aims to show the hardware and software of a solar powered autonomous node for wireless acoustic sensor networks based on ARM Cortex M4. The device consists of the following components: a microcontroller, four microphones for audio processing, a radio frequency communication module, a microSD to store and read data, four buzzers to emit a sound, a GPS, and a temperature sensor. Furthermore, the device can be powered by a battery or a solar panel. The device is characterized by low consumption and a small size.
Convention Paper 10085 (Purchase now)
P11-3 Vibrational Contrast Control for Local Sound Source Rendering on Flat Panel Loudspeakers—Ziqing Li, Institute of Acoustics, Chinese Academy of Sciences - Beijing, China; Pingzhan Luo, Institute of Acoustics, Chinese Academy of Sciences - Beijing, China; Chengshi Zheng, Institute of Acoustics, Chinese Academy of Sciences - Beijing, China; Xiaodong Li, Chinese Academy of Sciences - Beijing, China; Chinese Academy of Sciences - Shanghai, China
A vibrational contrast control method is proposed for two-dimensional audio display on a thin flat panel, which is based on maximizing the contrast of the average kinetic energy of the transverse motion between the radiated zone and the total zone. With the measured mobility matrix from the actuators to the measurement points, the optimal filter for each actuator is obtained based on the solutions of the maximization problem. The proposed method does not need to estimate both the natural frequencies and the modal shapes and therefore is easy to be implemented. Experimental results on an aluminum plate show that the proposed method can achieve high contrast level over a wide frequency range.
Convention Paper 10086 (Purchase now)
P11-4 Quantifying Listener Preference of Flat-Panel Loudspeakers—Michael Heilemann, University of Rochester - Rochester, NY, USA; David Anderson, University of Pittsburgh - Pittsburgh, PA, USA; Stephen Roessner, University of Rochester - Rochester, NY, USA; Mark F. Bocko, University of Rochester - Rochester, NY, USA
We present a perceptual evaluation of ?at-panel loudspeakers derived from anechoic amplitude response measurements. Seventy measurements were used to formulate frequency response curves for each loudspeaker characterizing the effects of listener position and in-room reflections. A model developed by Olive  was applied to the response curves to predict a preference rating for each loudspeaker. A commercial flat-panel speaker and a flat-panel speaker with a modal crossover network enabled/disabled were measured along with a conventional speaker. The modal crossover speaker scored over 10 points higher than the other flat-panel speakers and displayed a smooth low-frequency response. For flat-panel loudspeakers to produce preference ratings comparable with conventional speakers, structural improvements must be made to reduce the narrow band deviation at high-frequencies.
Convention Paper 10087 (Purchase now)
P11-5 Virtual Venues—An All-Pass Based Time-Variant Artificial Reverberation System for Automotive Applications—Friedrich von Türckheim, Harman Becker Automotive Systems GmbH - Munich, Germany; Adrian von dem Knesebeck, Harman Becker Automotive Systems GmbH - Munich, Germany; Tobias Münch, Harman International - Munich, Germany
This paper presents an arti?cial reverberation system for automotive applications. The core reverberation algorithm is based on a time-variant all-pass ?lter and delay network. It supports an arbitrary number of de-correlated ambience channels and enables the creation of individual direction-dependent early re?ection patterns for each output channel. Incorporating de-reverberation technology and microphones, the system allows for 3D direct-ambience upmixing of stereo content simulating the acoustics of existing concert halls as well as for actively modifying and improving the acoustics of car interiors. Ambisonics measurements of real rooms and concert halls serve as starting point for designing the virtual rooms. Adaptive effect stabilization guarantees a consistent spatial impression in presence of masking driving noise.
Convention Paper 10088 (Purchase now)
P11-6 Audio Portraiture –The Sound of Identity, an Indigenous Artistic Enquiry—Maree Sheehan, Auckland University of Technology - Auckland, New Zealand
To date the potential of 3D immersive and binaural sound technologies have not been applied to audio portraiture nor considered as a means of approaching and expressing indigenous identity. This paper looks at an artistic, practice-led study that utilizes the technology of 3D immersive and binaural sound technologies to create audio portraits and depictions of indigenous Maori women (wahine) from New Zealand/Aotearoa. This enquiry is part of my Ph.D. doctoral research that seeks to artistically interpret the identity and multiple-dimensionality of these women through sound. By multiple-dimensionality, I refer to historical, physical, cognitive, social, emotional, political, and spiritual dimensions of being.
Convention Paper 10089 (Purchase now)
P11-7 Precision Maximization in Anger Detection in Interactive Voice Response Systems—Inma Mohíno-Herranz, University of Alcalá - Alcalá de Henares, Madrid, Spain; Cosme Llerena-Aguilar, Sr., University of Alcalá - Alcala de Henares (Madrid), Spain; Joaquín García-Gómez, University of Alcalá - Alcalá de Henares, Madrid, Spain; Manuel Utrilla-Manso, University of Alcalá - Alcalá de Henares, Madrid, Spain; Manuel Rosa-Zurera, University of Alcalá - Alcalá de Henares, Madrid, Spain
Detection is usually carried out following the Neyman-Pearson criterion to maximize the probability of detection (true positives rate), maintaining the probability of false alarm (false positives rate) below a given threshold. When the classes are unbalanced, the performance cannot be measured just in terms of true positives and false positives rates, and new metrics must be introduced, such as Precision. “Anger detection” in Interactive Voice Response (IVR) systems is one application where precision is important. In this paper a cost function for features selection to maximize precision in anger detection applications is presented. The method has been proved with a real database obtained by recording calls managed by an IVR system, demonstrating its suitability.
Convention Paper 10090 (Purchase now)
P11-8 Automatic Guitar Tablature Transcription from Audio Using Inharmonicity Regression and Bayesian Classification—Jonathan Michelson, Electro-Harmonix / New Sensor Corporation - Queens, NY, USA; Richard Stern, Carnegie Mellon University - Pittsburgh, PA, USA; Thomas Sullivan, Carnegie Mellon University - Pittsburg, PA, USA
We propose two new methods to classify guitar strings for automated tablature transcription using only monophonic audio. The first method estimates the linear regression of log-inharmonicities of guitar strings with respect to their pitches and assigns unseen notes to the strings whose means and variances maximize the probability of their measured inharmonicities. The second method, developed as a baseline, characterizes the inharmonicity distribution of each fretboard position as a normal probability density, and then similarly assigns unseen notes to the fretboard positions that maximize the likelihood of their observed inharmonicities. Results from the standard Real World Corpus of guitar recordings show that exploiting regressions generally improves accuracy compared to our baseline, while both achieve adequate performance in guitar-independent test scenarios.
Convention Paper 10091 (Purchase now)
P11-9 Harmonic Drum Design Based on Multi-Objective Shape Optimization—Adam Szwajcowski, AGH University of Science and Technology - Kraków, Poland; Adam Pilch, AGH University of Science and Technology - Krakow, Poland
A vast majority of drums used in music have round membranes. Sound produced by such an instrument is non-harmonic, so one cannot perceive its pitch clearly. The paper aims to present possibilities of fusing additive synthesis and multi-objective optimization in order to find the relatively simple shape for which a membrane could produce harmonic sound. The proposed approach is based on Multi-Objective Particle Swarm Optimization and uses an original shape parametrization method based on Fourier series. Harmonicity of a drum was assessed based on additive synthesis using solutions of two-dimensional Helmholtz equation on irregular domains by means of the ?nite difference method.
Convention Paper 10092 (Purchase now)
P11-10 Troubleshooting Resource Reservation in Audio Video Bridging Networks—Christoph Kuhr, Anhalt University of Applied Sciences - Köthen, Germany; Alexander Carôt, Anhalt University of Applied Sciences - Köthen, Germany
The research project fast-music investigates the requirements of an infrastructure for 60 musicians of a conducted orchestra to do rehearsals via the public internet. Since a single server would not be able to handle the required amount of interleaved audio and video streams, process and distribute them again in a reasonable amount of time, a scalable cloud concept is more promising. The design of the realtime audio and video signal processing cloud, at the heart of a distributed live music session in the public internet, is operating on an Audio Video Bridging network segment. Such a realtime processing cloud requires a proper resource management for network resources. In this paper we present the concept for the processing cloud, evaluate on the resource management, and discuss a troubleshooting strategy for the stream reservation in Audio Video Bridging networks.
Convention Paper 10093 (Purchase now)
P11-11 The Sound Diffusion Simulation Software Basing on Finite-Difference Time-Domain Method—Kamil 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.
Convention Paper 10075 (Purchase now)