AES San Francisco 2008
Master Class Details
Thursday, October 2, 5:00 pm — 6:45 pmM1 - Basic Acoustics: Understanding the Loudspeaker
Presenter:
John Vanderkooy, University of Waterloo - Waterloo, Ontario, Canada
Abstract:
This presentation is for AES members at an intermediate level and introduces many concepts in acoustics. The basic propagation of sound waves in air for both plane and spherical waves is developed and applied to the operation of a simple, sealed-box loudspeaker. Topics such as the acoustic impedance, compact source operation, and diffraction are included. Some live demonstrations with a simple loudspeaker; microphone and measuring computer are used to illustrate the basic radiation principle of a typical electrodynamic driver mounted in a sealed box.
Friday, October 3, 9:00 am — 11:00 am
M2 - Binaural Audio Technology—History, Current Practice, and Emerging Trends
Presenter:
Robert Schulein, Schaumburg, IL, USA
Abstract:
During the winter and spring of 1931-32, Bell Telephone Laboratories, in cooperation with Leopold Stokowski and the Philadelphia Symphony Orchestra, undertook a series of tests of musical reproduction using the most advanced apparatus obtainable at that time. The objectives were to determine how closely an acoustic facsimile of an orchestra could be approached using both stereo loudspeakers and binaural reproduction. Detailed documents discovered within the Bell Telephone archives will serve as a basis for describing the results and problems revealed while creating the binaural demonstrations. Since these historic events, interest in binaural recording and reproduction has grown in areas such as sound field recording, acoustic research, sound field simulation, audio for electronic games, music listening, and artificial reality. Each of theses technologies has its own technical concerns involving transducers, environmental simulation, human perception, position sensing, and signal processing. This Master Class will cover the underlying principles germane to binaural perception, simulation, recording, and reproduction. It will include live demonstrations as well as recorded audio/visual examples.
Friday, October 3, 2:30 pm — 4:15 pm
M3 - Sonic Methodology and Mythology
Presenter:
Keith O. Johnson - Pacifica, CA, USA
Abstract:
Do extravagant designs and superlative specifications satisfy sonic expectations? Can power cords, interconnects, marker dyes and other components in a controversial lineup improve staging, clarity, and other features? Intelligent measurements and neural feedback studies support these sonic issues as well as predict misdirected methodology from speculative thought. Sonic changes and perceptual feats to hear them are possible and we'll explore recorders, LPs, amplifiers, conversion, wire, circuits and loudspeakers to observe how they create artifacts and interact in systems. Hearing models help create and interpret tests intended to excite predictive behaviors of components. Time domain, tone cluster and fast sweep signals along with simple test devices reveal small complex artifacts. Background knowledge of halls, recording techniques, and cognitive perception becomes helpful to interpret results, which can reveal simple explanations to otherwise remarkable physics. Other topics include power amplifiers that can ruin a recording session, noise propagation from regulators, singing wire, coherent noise, eigensonics, and speakers prejudicial to key signatures. Waveform perception, tempo shifting, and learned object sounds will be demonstrated.
Sunday, October 5, 9:00 am — 11:00 am
M4 - Acoustics and Multiphysics Modeling
Presenter:
John Dunec, Comsol - Palo Alto, CA, USA
Abstract:
This Master Class covers acoustics and multiphysics modeling using Comsol. The Acoustics Module is specifically designed for those who work in classical acoustics with devices that produce, measure, and utilize acoustic waves. Application areas include the design of loudspeakers, microphones, hearing aides, noise control, sound barriers, mufflers, buildings, and performance spaces.