In This Section
Journal of the AES
2011 September - Volume 59 Number 9
Call for Applications, Executive Director for the Audio Engineering Society, Inc.
Electrodynamic Transducer Model Incorporating Semi-Inductance and Means for Shorting AC Magnetization
Previous circuit models of dynamic moving-coil transducers that incorporated “semi-inductors” need to be extended in order to cover those cases that failed to adequately predict performance. The improved model takes into account semi-inductance, the effects of AC shorting devices, and the impact of frequency-dependent loss in the suspensions. As shown by the good agreement between the models and measurements, only a few additional components need be added to the model. This represents a more detailed physical understanding of loudspeaker behavior.
The rapid evolution of dedicated graphics hardware during the last decade allows for a dramatic increase in processing power for many audio applications that are unrelated to visual rendering. Modern graphical processing units can be used for audio processing in virtual reality and computer games. Their massively-parallel architecture offers 5- to 100-fold performance improvement compared to CPU implementations, as shown by such applications as audio rendering or speech recognition. Improved hardware features in the form of memory caches, multithreaded calls, better connection to the CPU, and standardized programming tools make them an attractive choice for compute-intensive audio applications.
Models that represent objective speech quality should include the influence of the cultural background of the listener as well as the particular language being spoken. Tests that evaluated American English and Igbo, an African tone language, revealed significant differences. Igbo listeners were more disturbed by additive noise and low listening levels. The low-level parts of the Igbo tone language appear to contain more critically important information than American English. Quality speech models must therefore be tuned to match the culture and language.
The second-order components of a spherical harmonics expansion of the sound pressure field can be obtained by means of velocity transducers based on hot-wire anemometry. Such velocity transducers are small compared to acoustic wavelengths and can be mounted on a tiny rigid bar only a few millimeters wide, thereby reducing the effects of wave diffraction and acoustic shadows. Numeric simulations and experimental tests using two Microflown pressure-velocity transducers validate the proposed approach.
Standards and Information Documents
AES Standards Committee News
Audio object metadata, core audio metadata
Binaural audio employs “head-related” signals to create the impression of spatial realism, but whose head and ears should be represented and does it make any difference? We summarize recent research in the field, presented at AES events.
46th Call for Papers, Denver
47th Call for Papers, Chicago