In This Section
Journal of the AES
2012 March - Volume 60 Number 3
AES President’s Message
When related audio control parameters are distributed in many devices in a high-speed audio network, a means for centralizing remote control and monitoring is required. Changes in one parameter may need to affect other parameters. The XFN protocol enables management of distributed parameters. This paper focuses on how to group related parameters that are physically separated and provides a corresponding implementation using the protocol. A comprehensive grouping theory is presented.
Typically, audio quality assessment uses MUSHRA (Multi Stimulus with Hidden Reference and Anchors), while speech quality assessment uses ACR (Absolute Category Rating). Since many applications are transporting both speech and music, such as mobile devices, a conversion technique between the two types of ratings would be useful. Two speech and two audio quality listening tests are compared with different content types. The results illustrate when and how the two types of measurements are consistent, complementary, and inconsistent.
A new speech quality model, DIAL (Diagnostic Instrumental Assessment of Listening), provides diagnostic information in both narrow-band and super wide-band contexts. It is “intrusive,” assuming that the original source audio is available. Because many quality-measuring techniques collapse all degradations into a single score, they do not help developers to diagnose the basis of that score. In contrast, the proposed DIAL model uses four quality dimensions: coloration, continuity, noisiness, and loudness.
The E-model for predicting speech quality mouth-to-ear can be extended with additional parameters to describe the effect of imperfect noise reduction and echo cancellation. As shown by subjective tests, quality-prediction accuracy of noise reduction and echo cancelling improves. Future work is planned to better refine the proposed approach.
Standards and Information Documents
AES Standards Committee News
44th Conference Report, San Diego
Increasingly sophisticated analysis, modeling, and simulation tools enable sound fields to be taken apart and put back together again in a modified form. They enable detailed control over the local acoustical environment, including aspects of its spatial characteristics and perceived qualities. This has a range of possible applications, such as the enhancement of natural sounds, spatial manipulation, personalized sound zones, and systems that can adapt to their environments.