A growing number of new technologies (e.g. low bit-rate coding) are based on specific properties of the auditory system, which are often highly non-linear. This means that the auditory quality of such systems cannot be measured by traditional physical measures (such as distortion, frequency response etc.), but only by perceptual evaluations in the form of listening tests. Perceptual Audio Evaluation provides a comprehensive guide to the many variables that need to be considered before, during and after experiments. Including the selection of the content of the programme material to be reproduced, technical aspects of the production of the programme material, the experimental set-up including calibration, and the statistical planning of the experiment and subsequent analysis of the data.
Author(s): Søren Bech, Nick Zacharov
Edition: 1
Publisher: Wiley
Year: 2006
Language: English
Commentary: 73840
Pages: 464
City: London; New York
Perceptual Audio Evaluation–Theory, Method and Application......Page 3
Contents......Page 9
Preface......Page 13
Organisation of the Book......Page 15
Acknowledgments......Page 21
1 Introduction......Page 23
1.1 Motivation for Listening Tests......Page 25
1.2 Role of Standardisation......Page 27
1.3 Role of Predictive Models......Page 33
I Experimental Considerations......Page 37
2 Definition of Research Question and Hypothesis......Page 39
2.1 Principle of Empiricism......Page 42
2.2 Principle of Rationalism......Page 43
2.3.1 Probabilistic Reasoning......Page 46
2.3.3 Conclusion by Analogy......Page 48
2.4 Summary......Page 49
3 Fundamentals of Experimentation......Page 51
4 Quantification of Impression......Page 61
4.1 Response Attribute......Page 62
4.1.1 Perceptual Measurements......Page 65
4.1.2 Affective Measurements......Page 87
4.2 Response Format......Page 89
4.2.1 Direct Scaling......Page 91
4.2.2 Indirect Scaling......Page 97
4.2.3 Selection of an Appropriate Scaling Procedure......Page 102
4.2.4 Context and Bias Effects......Page 108
4.2.5 Other Bias Effects......Page 114
4.3 Overview of Process......Page 118
5 Experimental Variables......Page 119
5.1.1 Signal Category......Page 121
5.1.2 Recording Technique, Storage and Encoding......Page 123
5.1.4 Spectral Characteristics......Page 124
5.1.5 Spatial Characteristics......Page 125
5.1.6 Reference Signals......Page 126
5.4 Subject Considerations......Page 127
5.4.1 Categorisation and Applicability......Page 128
5.4.2 Listening Panels......Page 134
5.4.3 Subject Selection......Page 140
5.4.4 Training and Monitoring......Page 158
6 Statistics......Page 163
6.1 Statistical Experimental Design......Page 166
6.2.1 Classification of Data Type......Page 183
6.2.3 Descriptive Level......Page 185
6.2.4 Inferential Level......Page 201
6.2.5 Statistical Checklist......Page 245
II Technical Considerations......Page 247
7 Electroacoustic Considerations......Page 249
7.1 Listening Rooms......Page 250
7.1.1 IEC 60268-13 Listening Rooms......Page 251
7.1.2 ITU-R Recommendation BS.1116-1 Listening Rooms......Page 253
7.1.3 EBU 3276 Listening Rooms......Page 258
7.1.4 General Characteristics......Page 261
7.2 Listening Booths......Page 266
7.3 Other Spaces......Page 268
7.4 Listener and Loudspeaker Positioning......Page 270
7.4.1 Monophonic Reproduction......Page 271
7.4.3 Multichannel Reproduction......Page 274
7.4.4 Separate Bass Loudspeakers......Page 276
7.4.5 Listener Position......Page 280
7.5 Accompanying Picture......Page 282
7.6 Commonly Encountered Problems......Page 283
7.7 Electrical Considerations......Page 285
8 Calibration......Page 287
8.1 Level Calibration......Page 289
8.1.1 Level Calibration Methods......Page 291
8.1.2 Level Metric Selection......Page 298
8.1.3 Preferred Listening Levels......Page 305
8.1.4 Reference Reproduction Levels......Page 307
8.2 Loudspeaker Calibration......Page 309
8.2.1 Level Calibration......Page 310
8.3.1 Headphone Types......Page 313
8.3.3 Headphone Measurement......Page 315
8.3.4 Target Frequency Response......Page 317
8.3.5 Level Calibration......Page 321
9.1.1 Experimental Planning......Page 323
9.1.2 Logistic Considerations......Page 325
9.1.3 Ethical Considerations......Page 328
9.2.2 Subject Familiarisation......Page 332
9.2.3 Listening Test Software......Page 337
9.3 Reporting......Page 341
III Applications......Page 345
10.1.1 ITU-T Recommendation P.800 Methods......Page 347
10.1.2 ITU-R Recommendation BS.1116-1......Page 352
10.1.3 ITU-R Recommendation BS.1534-1......Page 357
IV Appendices......Page 361
A Standards and Recommendations......Page 363
A.3 European Broadcasting Union......Page 364
A.4 International Electrotechnical Commission......Page 366
A.5.1 Telecommunications Standardisation Sector......Page 367
A.5.2 Radiocommunication Sector......Page 376
B Attribute Lists......Page 381
B.1 Speech Quality......Page 382
B.2.1 Loudspeakers......Page 385
B.2.2 Headphones......Page 388
B.3 Other Quality Attributes......Page 392
C Audio Source and Demonstration Material......Page 395
D A-, B-, C- and D-Weighting Curves......Page 399
E DRP-ERP Compensation Curves......Page 401
F Abbreviations......Page 403
Bibliography......Page 411
Index......Page 457
