Report of the meeting of SC-02-02 Working Group on digital input/output interfacing of the SC-02 Subcommittee on Digital Audio, held in San Francisco, CA., US., 2006-10-04
The meeting was convened by R. Chalmers in place of chair J. Grant.
The agenda and the report of the previous meeting, held 2006-05-19 in Paris, were accepted as written.
Open Projects:
AES-R4-R: Review of AES-R4 2002: Guidelines for AES standard for digital audio - Digital input-output interfacing - Transmission of digital audio over asynchronous transfer mode (ATM) networks, AES47
A revision is needed to complement the recent revision of AES47. Input from Grant is expected soon.
AES-R6: Guidelines for AES50 (HRMAI)
M. Page will review these Guidelines to complement proposed revisions to AES50.
AES-2id-R: Review of AES-2id-1996 (r2001): AES information document for digital audio engineering - Guidelines for the use of the AES3 interface
A further four weeks will be allowed for further comments on the draft new edition (which has been secretariat formatted) before the PCFC will issued. Chalmers thanked R. Caine for his efforts on the major revision of this document.
AES-3id-R: Review of AES-3id-2001: AES information document for digital audio engineering - Transmission of AES3 formatted data by unbalanced coaxial cable
M. Yonge reported that comments received so far on the CFC have been resolved.
However it was intended in future to revise the document to include higher sampling frequencies. Noted that SMPTE group A29 are working in this area.
AES-10id-R: Review of AES-10id-2005: AES information document for digital audio engineering - Engineering guidelines for the multichannel audio digital interface (MADI) AES10
No action was required before 2010 or requested.
AES3-R: Review of AES3-2003: AES Recommended practice for digital audio engineering - Serial transmission format for two channel linearly represented digital audio data
Caine is continuing with the complex task of restructuring this document in layered form. It is hope a draft will be available by 2007
AES5-R: Review of AES5-2003: AES recommended practice for professional digital audio - Preferred sampling frequencies for applications employing pulse-code modulation
No action was required before 2008 or requested.
AES10-R: Review of AES10-2003: AES Recommended Practice for Digital Audio Engineering - Serial Multichannel Audio Digital Interface (MADI)
No action was required before 2008 or requested.
AES11-R: Review of AES11-2003: AES Recommended Practice for Digital Audio Engineering - Synchronization of digital audio equipment in studio operations
No action was requested or required before 2008
AES18-R: Review of AES18-1996 (r2002): AES recommended practice for digital audio engineering - Format for the user data channel of the AES digital audio interface
No action required before 2007. This document is not expected to be revised in future.
AES41-R: Review of AES41-2000 (r2005): AES standard for digital audio - Recoding data set for audio bit-rate reduction
No action required before 2010 or requested.
AES47-R: Review of AES47-2006: AES standard for digital audio - Digital input-output interfacing - Transmission of digital audio over asynchronous transfer mode (ATM) networks
Caine is expected to provide a amendment to complement the publication of AES-X148, currently under CFC.
AES50-R: Review of AES 50-2005 High Resolution Multichannel Audio Interconnection (HRMAI)
Page has provided the secretariat with material for an amendment to correct and clarify parts of the specification, particularly on how a receiver should behave under error conditions.
AES51-R: Review of AES51-2006: AES standard for digital audio - Digital input-output interfacing - Transmission of ATM cells over Ethernet physical layer
No action requested or required before 2011.
AES52-R: Review of AES52-2006, Insertion of unique identifiers into the AES3 transport stream
No action requested or required before 2011.
Development projects:
AES-X139: Liaison with EBU P/AGA
Chalmers reported that the EBU group had not discussed any subjects within the scope of the SC-02-92
AES-X148: Sample-accurate timing in AES47
This document is currently under CFC.
AES-X121: Synchronisation of digital audio over wide areas
Grant & C. Chambers will produce draft report as a basis for further discussion.
Liaisons:
P. Treleaven offered an informal liaison with SMPTE groups A29 and S22.
New Projects:
A proposal for project on a Digital Interface for Loudspeakers will be discussed further before a PIR is submitted.
A proposal to consider audio/video synchronisation ("lip sync"), currently under discussion in IEC and SMPTE, was discussed in this group but needs further clarification. An informal liaison with SMPTE S22 was proposed as a means of clarifying working parameters.
New Business:
There was no new business.
The next meeting will be scheduled in conjunction with the AES 122nd Convention in Vienna, Austria, 2007-05.
