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Perceptual Effects of Dynamic Range Compression in Popular Music Recordings - January 2014
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Accurate Calculation of Radiation and Diffraction from Loudspeaker Enclosures at Low Frequency - June 2013
9 comments

New Measurement Techniques for Portable Listening Devices: Technical Report - October 2013
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Journal of the AES


2003 September - Volume 51 Number 9

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Papers

In Memoriam: Patricia Macdonald (PDF-21K)        Roger K. Furness    779
 
PAPERS
Effects of Down-Mix Algorithms on Quality of Surround Sound (PDF-163K)  
Slawomir K. Zielinski, Francis Rumsey, and Søren Bech    780
When channel limitations prevent the transmission of a full 5.1 surround mix, there are many options for converting to a lesser number of channels using down mixing. Listeners were asked to evaluate eight different algorithms from two listening positions in terms of preferences rather than quality. Unfortunately, different audio cases produced variations in the conclusion about optimum. The presence of a video picture influenced the experience of reduced audio channels.  
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A Study on Head-Shape Simplification Using Spherical Harmonics for HRTF Computation at Low Frequencies (PDF-118K)  
Yufei Tao, Anthony I. Tew, and Stuart J. Porter    799
Using a simplified shape for the human head in computing head-related transfer functions (HRTFs) produces errors in the calculated pressures on the surface. A model of a head can be represented as a series of spherical harmonics. This study computes the errors in acoustic pressure that result from truncating the series, which corresponds to low-pass shape filtering. These shape errors follow the corresponding pressure errors for frequencies below 3 kHz. Harmonics to order 11 are sufficient for the low frequencies representation of a head. Beyond order 14 there is no additional improvement.  
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Differences in Performance and Preference of Trained versus Untrained Listeners in Loudspeaker Tests: A Case Study (PDF-271K)  
Sean E. Olive    806
The audio industry makes many assumptions about the appropriateness of various quality testing methods, but there have not been any significant studies to validate these assumptions. The choices are reduced to using trained listeners, who are efficient and discriminating, or untrained listeners, who are more representative of the user population. This 18-month study shows that trained listeners produce the same conclusion as 268 untrained listeners when evaluating loudspeakers.  
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Objective Measures of Listener Envelopment in Multichannel Surround Systems (PDF-350K)  
Gilbert A. Soulodre, Michel C. Lavoie, and Scott G. Norcross    826
Predicting the degree of listener envelopment is more complex than the traditional measures of lateral energy after the first 80 ms. This detailed study shows that the transition threshold between early and late energy is frequency-dependent. In addition, the loudness of the lateral energy is equally important. A new objective measure is proposed with a very high correlation between perceived envelopment and the calculated metric.  
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LETTERS TO THE EDITOR
"More Comments on President's Message and Comments" (PDF-6K)        John Woodgate    841
 
STANDARDS AND INFORMATION DOCUMENTS
AES Standards Committee News (PDF-17K)    842
Sampling frequencies; digital audio synchronization; preservation and restoration of recordings; loudspeaker modeling and measurement  
 
FEATURES
23rd Conference Report, Copenhagen (PDF-1.6MB)    846
Digital Rights Management (PDF-382K)    855
25th Conference, London, Call for Papers (PDF-16K)    871
 
DEPARTMENTS
News of the Sections (PDF-274K)    861
Sound Track (PDF-69K)    865
New Products and Developments (PDF-72K)    867
Upcoming Meetings (PDF-30K)    868
Available Literature (PDF-85K)    869
Membership Information (PDF-86K)    872
Advertiser Internet Directory (PDF-81K)    873
Sections Contacts Directory (PDF-33K)    874
AES Conventions and Conferences (PDF-47K)    880
 
EXTRAS
Cover & Sustaining Members List (PDF-33K)    
VIP List & Editorial Staff (PDF-27K)    
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