In a highly advanced, yet-remarkably simple audio system design that points to the future of professional-grade integration, On Stage Audio (OSA) this month deployed the world’s first real-world test of the IEEE 802.1 AVB Bridging protocol. OSA’s team, led by Jim Risgin, Vice President, configured and controlled a Crown Audio, dbx, and BSS Audio A/V system using Harman HiQnet for the Compuware national sales meeting in Detroit, Michigan and ran audio using Ethernet AVB standards. The event, which took place at the Masonic Theater in downtown Detroit, allowed a crowd of 1,500 attendees to enjoy pristine digital audio and let the audio systems crew experience the future of A/V systems configuration, one in which everything works, all the time, and in which simplicity, not complexity, is the norm.

This watershed event marked the first time that AVB — the only standard transport protocol that allows time-synchronized, super-low-latency streaming audio and video over IEEE 802 Ethernet networks – was used as the primary audio transport for a major professional system. Harman is a leader in the AVB initiative, chairing and editing the IEEE P1722 Committee and editing the IEEE P802.1Qat Committee and the company is also a pioneer in AVB switching and product development, via the groundbreaking efforts of the Harman Corporate Technology Group and System Development and Integration Group (SDIG). Their dedication to the development of AVB is signified by their membership in the AVnu Alliance; the industry forum dedicated to promoting the adoption of the IEEE 802.1 AVB and related IEEE 1722 and IEEE 1733 standards over various networking link-layers for the advancement of professional quality audio video.

At the core of Risgin’s design are 24 Crown CTs 3000 power amplifiers fitted with USP4/AVB cards, four 24-port BSS Audio / NETGEAR AVB bridges as well as four dbx SC 32 Digital Matrix Processors which were used as the AVB “on ramps” for the system processing. The entire system (DSP and AVB) was controlled using Harman’s HiQnet protocol and System Architect software.

Jim Risgin, himself an early and active contributor to the AVB movement, assembled the Compuware AVB system working closely with SDIG. Using the intuitive and customizable HiQnet System Architect drag-and-drop design interface to design his system, Risgin configured and programmed the dbx SC 32 Digital Matrix Processor for processing and using the AVB network as the matrix automatically instructed groups of Ethernet AVB amplifier channels associated with each physical zone to switch to that networked audio signal.

The dbx SC 32’s were deployed as the ‘on ramps’ were used to convert the incoming analog audio to digital AVB streams. Fourteen audio streams were then routed via HiQnet System Architect to the 24 Crown CTs amplifiers with Crown USP4 4th generation DSP-based PIP™ (Programmable Input Processor) input modules connecting the amplifiers to the Ethernet network. This enabled real-time transport of digital audio via Ethernet AVB and also allowed the CTs amplifiers to be remotely controlled and monitored via HiQnet System Architect.

“The systems performed flawlessly,” says Risgin, who notes that AVB-induced latency was less than 500 microseconds for all devices, and that delay from input to output maintained the