Introducing the Free Web Edition of the “Perceptual Audio Coders – What To Listen For” Educational Material

In 2001, the AES Technical Committee on Coding of Audio Signals (TC-CAS) produced the legendary educational CD ROM "Perceptual Audio Coders - What To Listen For". It contains a taxonomy of common types of codec artifacts, as well as tutorial information on the background of each one. Example audio signals with different degrees of impairment illustrate the nature of the artifacts and help in training test listener expertise. Since its initial release, several generations of CD ROMs were sold and found worldwide use for education of the public. This paper presents the results of the Technical Committee's efforts in producing a second-generation educational package that adds tutoring on new artifact types as they can be typically experienced with advanced audio codec processing (e.g. bandwidth extension or parametric stereo) and educates on subjective quality evaluation. Moreover, the format of the material was enhanced for seamless display and playback on PCs, tablets and mobile phones and includes interactive graphics elements. This makes it an attractive educational package that is now available freely on the web.