2005 March, Volume 53 Number 3

CONTENT

PAPERS

Vertical Localization of Sound from Multiway Loudspeakers
Sam Ferguson and Densil Cabrera   163
While most loudspeaker designers are concerned with localization in the horizontal plane, perceived vertical location usually does not receive sufficient attention. When synchronous and asynchronous noise bands at high and low frequencies are presented, the vertical locations of each signal are not necessarily aligned. Moreover, the location of the high-frequency band tends to dominate the location of the low-frequency band when both are simultaneously present.

Comparison of Basic Audio Quality and Timbral and Spatial Fidelity Changes Caused by Limitation of Bandwidth and by Down-Mix Algorithms in 5.1 Surround Audio Systems
Slawomir K. Zielinski, Francis Rumsey, Rafael Kassier, and Søren Bech   174
When there is inadequate channel bandwidth to transmit full high-quality audio in multiple surround channels, spatial fidelity should be sacrificed. Mixing down multiple channels to a smaller number is preferred over limiting the bandwidth of all channels. Timbral quality is a more important contributor to basic audio quality than spatial quality in the context of modern home cinema systems.

Intercomparison Measurements of Room Acoustical Parameters and Measures for Speech Intelligibility in a Room with a Sound System
Kurt Eggenschwiler and Rainer Machner   193
The qualitative control of specifications for sound systems and rooms is becoming more and more important. But what is the uncertainty of the related acoustics measurements? Intercomparison measurements showed that the standard deviations were often within the region of the perception thresholds. Achieving consistent results may depend on such factors as better training of acousticians.

COMMUNICATIONS

Wavetable Synthesis Strategies for Mobile Devices
Robert C. Maher   205
Unlike the design choices made for wavetable synthesis of music, strategies for customized ring tones in cell phones and pagers require a different optimization. In this application: higher levels of compression are needed; memory storage is limited; and compute power is sparse. However, by careful selection of the sample set and its representation during encoding, a new strategy achieves 12-bit performance with up to 50% compression.

STANDARDS AND INFORMATION DOCUMENTS
Audio over IEEE 1394; Internet audio quality; analog recording; transfer technologies; storage and handling of media; digital library and archive systems; forensic audio; sound source modeling; loudspeaker measurement; grounding and EMC practices   214

FEATURES

118th Convention Preview, Barcelona   218
List of Exhibitors and Previews   220
New Developments in Low Bit-Rate Coding   235
119th Convention, New York, Call for Papers   263

DEPARTMENTS

News of the Sections   242
Upcoming Meetings   245
Sound Track   246
Available Literature   249
Membership Information   250
Advertiser Internet Directory   251
In Memoriam   261
AES Annual Report   264
Sections Contacts Directory   265
AES Conventions and Conferences   272

FPO For the cover:

2005 March, Volume 53 Number 3

spine: 2005 March, Volume 53 Number 3