AES Standards News Blog

A new Information Document, AES-12id-2006, AES Information Document for digital audio measurements - Jitter performance specifications, has been published. The question of sample-clock quality is a perennial one for digital audio equipment designers, yet most chip makers provide very little information about the jitter performance of their products. Consequently, equipment designers are sometimes caught out by jitter issues. The increasing use of packet-based communications and class-D amplification is throwing these matters into sharper relief. This information document reviews various ways of characterizing and quantifying jitter, and refines several of them for audio purposes. It also attempts to present a common, unambiguous terminology. Its focus includes wideband jitter, baseband jitter, jitter spectra, period jitter, long-term jitter and jitter signatures. Comments are made on jitter transfer through phase-locked loops and on the jitter susceptibility of audio converters.

http://www.aes.org/publications/standards/search.cfm?docID=57

A substantially updated Information Document, AES-6id-2006, AES information document for digital audio - Personal computer audio quality measurements, has been published. This document focuses on the measurement of audio quality specifications in a PC environment. Each specification listed has a definition and an example measurement technique. Also included is a detailed description of example test setups to measure each specification. There have been many improvements in PC audio since the original AES-6id document was published. This revision of AES-6id-2000 includes substantial updates that reflect the improvements in the PC sound sub-system, as well as some updates based on many real world measurements.

http://www.aes.org/publications/standards/search.cfm?docID=6

A new Information Document, AES-11id-2006, Extended term storage environment for multiple media archives has been published. This information document provides guidelines for archivists faced with storing a variety of audio, still image and moving image media in a single storage environment. This circumstance is faced by many archivists in small and medium size archives that must preserve and make available the wide variety of media from nitrate film to optical discs. These guidelines provide recommendations to harmonize storage recommendations contained in standards and recommended practices published by the AES and the International Standards Organization (ISO).

http://www.aes.org/publications/standards/search.cfm?docID=56