VOLUME 48 NUMBER 12, 2000 December

CONTENT

PAPERS

A Unified Theory of Horizontal Holographic Sound Systems
M. A. Poletti 1155

A theoretical basis for a horizontal holographic surround sound system, using the two-dimensional Fourier transform, is presented in depth. It is shown how the theory leads to the recording and reproduction of sound fields using circular arrays of microphones and loudspeakers. The reproduction of a five-loudspeaker surround system is also examined, and its performance over wider reproduction areas is considered.

DSP Equalization of Electret Film Pickup for the Acoustic Guitar
Matti Karjalainen, Vesa Valimaki, Henri Penttinen, and Harri Saastamoinen 1183

The sound quality of a guitar's bridge electret film pickup does not match that of the instrument's acoustic sound. To enhance the instrument's pickup sound and to simulate its acoustic attributes, the authors have applied digital signal processing to recreate its acoustic sound characteristics. If the equalizer uses a programmable digital signal processor, additional features such as various sound effects or a reverberation function can be added easily.

An Air-Cored Autotransformer with Nearly Equal Decibel Taps
A. N. Thiele 1194

An autotransformer as the first shunt inductor at the input of a high-pass filter serving as a crossover element in a loudspeaker system permits the level adjustment of individual drivers without changing the frequency or phase response. This arrangement eliminates interaction with other drivers in the system array when the individual levels are adjusted to equalize the differences in driver sensitivities. There are numerous circuit examples given which can assist in implementing this concept.

ENGINEERING REPORTS

Loudspeaker Response Improvement Using Cone Thickness Variation
David Featherston and Michail Barabasz 1216

The effect a variation in a loudspeaker's cone body thickness has on a felted paper cone has been studied. A modified cone thickness profile with changes at a given radius showed improved high-frequency response in this study. It was further shown that thickness modifications can be used to reduce diaphragm mass and lead to improved overall loudspeaker efficiency.

Standards and Information documents
AES Standards Committee News 1221

Working group reorganization; digital measurement; file exchange; system control; microphones; acoustic files; flutter; synchronization

FEATURES

DVD-Audio Specifications Norihiko Fuchigami, Toshio Kuroiwa, and Bike H. Suzuki 1228

2000/2001 AES International Sections Directory 1241

Education News 1263

Call for Nominations for Board of Governors 1271

Call for Nominations for Awards 1272

10th Tokyo Regional Convention, Call for Papers 1280

111th Convention, New York, Call for Papers 1281

Bylaws: Audio Engineering Society, Inc. 1282

Index to Volume 48 1286

DEPARTMENTS

News of the Sections 1264

Upcoming Meetings 1265

Sound Track 1266

New Products and Developments 1268

Available Literature 1270

Membership Information 1273

Advertiser Internet Directory 1277

In Memoriam 1278

AES Conventions and Conferences 1296

FPO For the cover:

Volume 48 Number 12 2000 December

spine: Volume 48 Number 12 2000 December