The first presentaton in the AES Standards webinar series will take place on March 29 at 12:00 noon, ET, and will feature Merlijn Van Veen and Roger Schwenke, co-chairs of the SC-04-03-A Task Group, discussing measurement of loudspeaker maximum SPL using random noise that simulates music.
Van Veen and Schwenke will discuss the work of the SC-04-03-A Task Group developing a procedure for loudspeaker test and measurement using a test signal called M‑Noise. It is unique in that its crest factor as a function of frequency mimics that of real music, better simulating what transducers encounter in use than previous methods using pink noise. They will briefly explore the background and impetus for this project and the challenges it may solve. The standard’s procedure will be explained and demonstrated using readily available equipment. Included will be a discussion of challenges that arose during the standard development, but also how it inspired different applications within other standard bodies. The presentation will review the timeline for remaining work and describe how you can get involved.
AES members may register for the Zoom webinar to enjoy live interaction with the presenters, while non-members may watch a live stream of the event on the AES YouTube channel: youtube.com/user/AESorg
Register for the webinar at the link below.
Posted: Friday, March 19, 2021
The AES Standards Committee is launching a webinar series to highlight the various standards under development. Each webinar will focus on the efforts of an individual Working Group or Task Group. The presentations will cover the current activity of the group, the origins of the project, the current state of development and the expectations for the completed document. When possible, presentations will include demonstrations of the technology involved.
Posted: Tuesday, March 9, 2021
Remaining reports of the October AES Standards Working Group meetings are now online.
SC-02-08 on Audio File Transfer and Exchange
SC-03-06 on Digital Library and Archive Systems
SC-04-03 on Loudspeaker Modeling and Measurement
SC-04-09 on Assessment of Acoustic Annoyance
SC-05-05 on Grounding and EMC practices
SC-07-01 on Audio Metadata
Posted: Monday, March 8, 2021
AES69-2020, "AES standard for file exchange – Spatial acoustic data file format", a revised version of AES69-2015 has been published.
Posted: Thursday, February 4, 2021
This standard provides a convention for expressing edit data in text form in a manner that enables simple and accurate computer parsing while retaining human readability. It also describes a method for expressing time-code information in character notation. It supports common professional audio sampling frequencies, video frame rates, and film framing. This document addresses the core need of the AES31 series of standards in providing a simple but extensible system for passing audio material between systems.
The SMPTE Universal Label identified in Annex F.2 was provided by SMPTE as a Leaf in the metadata dictionary for 'Audio edit decision list (ADL) defined in AES31-3'. Also defined is a Node in the metadata dictionary for 'File exchange metadata defined in AES standards'. This means that further file-exchange labels can be generated more easily in the future.
Posted: Tuesday, December 22, 2020
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.
This revision removes culturally insensitive terms from the text and corrects minor editorial issues. It is available now in the Standards Store.
Posted: Wednesday, December 16, 2020
AES17 defines a digital Full Scale and 0 dB FS as the level of a sinewave whose peaks reach the largest positive digital code. Some incorrectly display full scale sinewaves as -3 dB FS. The AES17-2020 revision is an effort to eliminate this confusion.
Originally released in 1991, AES17 introduced and defined the measurement of 0 dB FS. This definition has remained unchanged through revisions of the standard in 1996, 1998 and 2015. The 2015 revision added notes to clarify the proper calibration of dB FS. The 2020 revision further expands on these notes.
The 2020 revision will be available for download on 2020/12/11
Posted: Wednesday, December 9, 2020
The Call for Comment on DRAFT AES69-2020, " AES standard for file exchange – Spatial acoustic data file format " was published 2020-12-08.
Binaural listening is growing fast, because of growing sales in smartphones, tablets and other individual entertainment systems. The lack of a standard for the exchange of head-related transfer functions (HRTF) means each company keeps its binaural capture and rendering algorithms private. 3D audio is arising, and binaural listening could be the very first 3D audio vector with sufficient fidelity of HRTF.
The use of convolution-based reverberation processors in 3D virtual audio environments has grown with the increase in available computing power. Convolution-based reverberators guarantee an authentic and natural listening experience, but also depend on the acoustic quality of the applied spatial room impulse response (SRIR).
With a standardized file format for HRTF and SRIR data, each company can contribute its best algorithms, providing good personalized capture and/or rendering, allowing the consumer to choose a combination of technologies for the best quality of experience.
This document standardizes a file format to exchange space-related acoustic data, such as binaural listening parameters in the form of head related transfer functions. The format is scalable to match the available rendering process and is designed to include source materials from different databases.
Posted: Sunday, December 6, 2020
The AES has launched a survey on AES74 Conformance. This survey will assess the conformance of various media network directory schemes with AES74, the recently-published AES standard that sets forth technical requirements for media network directories and related services.
The survey is based on a downloadable questionnaire that may be filled out by proponents of directory schemes, by AES standards workers, or by a collaboration of the two.
The completed questionnaires will be collated and summarized by AES standards workers. Survey conclusions will be published in an AES Report. AES Reports are non-normative documents that provide information.
The survey will not evaluate, review, or compare directory schemes or their implementations. It will simply report on the AES74 conformance of each.
The results will be of interest to network media equipment manufacturers, to media system designers, and to media company technical architects and strategists.
Proponents of all media network directory schemes, whether public or proprietary, are encouraged to download and complete the survey instrument and forward the results to the AES according to the instructions given in the document.
If you make, use, or know of a directory scheme that should be included, please email [email protected].
The AES Standards Committee has identified a list of well-known directory schemes it believes should be represented in the survey. Members of AES Standards Task Group AES-SC-02-12-N will be explicitly contacting the owners of these schemes to ensure their representation in the final report.
The closing date for completed questionnaire submission is February 28, 2021.
Posted: Tuesday, November 3, 2020
Several reports of the October AES Standards Working Group meetings are now online.
SC-02-01 on Digital Audio Measurement
SC-02-02 on Digital Audio Input/Output interfacing
SC-03-12 on Forensics
SC-04-04 on Microphone Measurement and Characterization
SC-04-08 on Measurement and Equalization of Sound Systems in Rooms
SC-05-02 on Audio Connectors
Additional reports will be posted as they become available.
Posted: Monday, November 2, 2020
