AES-R6-2011, AES project report - Guidelines for AES standard for digital audio engineering - High resolution multi-channel audio interconnection (HRMAI), AES50 has been published
This edition revises AES-R6-2005 to complement the latest revision of AES50.
This report is intended to accompany AES50, “High-resolution multi-channel audio interconnection”. It provides additional background, rationale and implementation advice and should be read in conjunction with AES50-2011 which revises the earlier AES50-2005. In particular, the first clause of this document provides an overview of the technology, which may aid understanding of the context of the standard.
The High Resolution Multi-channel Audio Interconnection provides a bi-directional, point-to-point connection for up to 48 channels of digital audio in a variety of formats. The link uses a single Category 5 (or better) structured-wiring data cable, and is designed for operation in a studio environment.
The system uses the 100Base-TX physical layer of Fast Ethernet (ISO/IEC 8802.3:2000(E) Sections 22/23, together with ANSI X3.263-1995) to transfer framed digital audio data. Audio synchronization is maintained by transmitting a 64fs (for example, 2,8224 MHz, if fs = 44,1 kHz) audio clock signal in parallel with the audio data, utilising the extra signal pairs on a structured wiring data cable.
Throughout this document, the term “fs” is used to denote a base audio sampling frequency. This may be 44,1 kHz or 48 kHz, irrespective of sampling frequency multipliers typically used for high-resolution digital audio (e.g. 2, 4, 8). If variable sample rate operation (“varispeed”) is required, fs may range from 44,1 kHz -12,5 % to 48 kHz +12,5 % (38,5875 kHz to 54 kHz). Varispeed capability is optional.
Posted: Thursday, September 22, 2011