2007 December, Volume 55 Number 12

CONTENTS

PAPERS

Degradation Decomposition of the Perceived Quality of Speech Signals on the Basis of a Perceptual Modeling Approach
John G. Beerends, Bartosz Busz, Paul Oudshoorn, Jeroen van Vugt, Kamal Ahmed, and Omar Niamut   1059
Extensive research has already provided metrics that can evaluate the quality of speech on nonideal channels, such as cell phones. In order for engineers to evaluate these quality measures, the present study decomposes degradation into three components and then explores the way in which each contributes to the overall perceived speech quality. These degradations include additive noise, time-invariant frequency response limitation, and time-response degradation, such as clicks and lost packets. The correlation between the proposed approach and subjective rating was found to be around 0.9.

Comparison of Four Subwoofer Measurement Techniques
Manuel Melon, Christophe Langrenne, David Rousseau, and Philippe Herzog   1077
The difficulty in evaluating loudspeakers at very low frequencies is illustrated by comparing four different techniques for evaluating subwoofer directivity and frequency response. Because measurement rooms have dimensions that are small compared to these very large wavelengths, subwoofer loudspeakers cannot be observed without also considering the acoustic influence of the environment. The four techniques vary in terms of their required assumptions, a priori knowledge, cost of making measurements, and the accuracy of the results.

Analysis of Multiactuator Panels in Space-Time Wavenumber Domain
Basilio Pueo, José J. Lépez, José Escolano, and Sergio Bleda   1092
A method for analyzing the radiation patterns and spatial aliasing of wave field synthesis demonstrates the strengths and weaknesses of multiactuator panels and arrays of conventional loudspeakers. The analysis was performed in the space-time wavenumber domain, which combined time and spatial frequencies. Because spatial truncation and array directivity create aliasing artifacts at various listener positions, there is a performance tradeoff in the size of the panels and the spacing of actuators.

Adaptive Wave Field Synthesis for Sound Field Reproduction: Theory, Experiments, and Future Perspectives
Philippe-Aubert Gauthier and Alain Berry   1107
Because the algorithms used for wave field synthesis recreate a sound field with the assumption of being an anechoic space, a real space with its own acoustics often dramatically reduces the reproduction accuracy. By modifying the foundation mathematics, the algorithm can be made to adapt to the actual acoustics of a space. A penalty function allows for control over the degree to which adaptation is achievable. An experimental evaluation of two algorithms showed that independent radiation mode control enlarges the accuracy within the listening area. Adaptive wave field synthesis can be applied to many configurations.

STANDARDS AND INFORMATION DOCUMENTS

AES Standards Committee News   1125
Subjective evaluation of loudspeakers; forensic audio; AES3 status data; audio applications of networks; acoustics and sound source modeling; microphone measurement; audio connectors

FEATURES

13th Tokyo Regional Convention Report   1128
     Exhibitors   1133
32nd Conference Report, Hillerød, Denmark   1134
123rd Convention Report, New York   1142
     Exhibitors   1156
High Resolution Audio   1161
Education News   1168
Call for Nominations for the Board of Governors   1180
Call for Awards Nominations   1181
33rd Conference, Denver, Call for Papers   1188
34th Conference, Seoul, Call for Papers   1189
Bylaws: Audio Engineering Society, Inc.   1190
Index to Volume 55   1194

DEPARTMENTS

Upcoming Meetings   1169
News of the Sections   1170
New Products and Developments   1177
Available Literature   1179
Membership Information   1182
Advertiser Internet Directory   1185
Sections Contacts Directory   1208
AES Conventions and Conferences   1216

FPO For the cover:

2007 December, Volume 55 Number 12

spine: 2007 December, Volume 55 Number 12