2003 June, Vol 51 Number 6

CONTENT

PAPERS

Effects of Bandwidth Limitation on Audio Quality in Consumer Multichannel Audiovisual Delivery Systems
Slawomir K. Zielinski, Francis Rumsey, and Søren Bech   475
Peak voice-coil displacement is an important parameter for specifying the maximum acoustic output at low frequencies. However, the absence of a single definition for distortion produces ambiguous results that can not be easily compared. For example, choices include distortion in the voice-coil current or cone displacement. Alternatively, a parametric method that provides more detailed information about the cause of the distortion is proposed. A comparison between performance-based and parameter-based techniques illustrates the advantages and disadvantages.

An Efficient Algorithm for the Restoration of Audio Signals Corrupted with Low-Frequency Pulses
Paulo A. A. Esquef, Luiz W. P. Biscainho, and Vesa Välimäki   502
Restoring old recordings, especially those that contain clicks at the boundaries where pieces of a broken record have been glued together, requires a model of the corruption. In addition to the transient itself, the cartridge responds to the transient with a long-tailed, low-frequency impulse response, which must also be removed. The authors propose a computationally efficient algorithm, called two-pass split-window filtering, to model and remove this additional component. The results are compared with an autoregressive algorithm.

ENGINEERING REPORTS

Study on the Relationship between Some Room Acoustical Descriptors
D. Ouis   518
An acoustic model of a performance space provides a means for evaluating those physical measures that predict the subjective experience, such as spaciousness. In order to evaluate the relationship between the various metrics over the space, the author simulated a rectangular space with an additional pair of sidewall balconies. Image reflections and diffraction effects were included to make the model more representative of a real space. This allowed the relationship among parameters to be evaluated.

Automated Parameter Optimization for Double Frequency Modulation Synthesis Using a Tree Evolution Algorithm
B. T. G. Tan and N. Liu   534
As a means of synthesizing complex sounds, several frequency modulation techniques have become popular. However, finding the ideal frequency and amplitude modulation waveforms to create a target signal is difficult, ad hoc, and prone to nonoptimum results. Many optimization algorithms tend to converge to a local solution without adequately exploring the entire space for better solutions. The proposed approach separately explores each local solution rather than focusing on a single part of the space.

STANDARDS AND INFORMATION DOCUMENTS

AES Standards Committee News   547
Level meters; digital interfacing; digital synchronization; forensic audio; microphone measurements; audio applications of IEEE 1394

FEATURES

History of Spatial Coding   Mark F. Davis   554
Automotive Audio   570
New Media for Music: An Adaptive Response to Technology   575
Updates and Corrections to the 2002/2003 International Sections Directory   578
Education News   580
116th Convention, Berlin, Call for Papers   596

DEPARTMENTS

News of the Sections   582
Upcoming Meetings   587
Sound Track   588
New Products and Developments   589
Available Literature   591
Membership Information   592
Advertiser Internet Directory   593
In Memoriam   594
AES Special Publications   597
Sections Contacts Directory   602
AES Conventions and Conferences   608

FPO For the cover:

2003 June, Vol 51 Number 6

spine: 2003 June, Vol 51 Number 6