Alongside this is AVB, an IEEE standards based technology that could stand on its own or underpin many of the existing networked audio protocols.

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1 AES67 and AES70 The complete industry solution for audio and control Over the past three decades the audio industry has taken a number of steps to move into the digital age. Some argue that the digital transition seems almost complete, whilst others look at the vast array of audio technology and think that there is still so much missing. Over the years we ve seen countless audio connection schemes come and go. These physical parts always seem to sit separately from attempts to help our equipment work together better. Meanwhile the IT industry has been moving forward, giving us impossible amounts of audio processing along with the networking technology that we increasingly use to transport audio and our all so important control messages. Digital signal processing is now so cheap that it can be implemented in almost any audio product. We started with point-to-point audio connections, from standard two-channel AES3 to MADI offering up to 64 channels of audio over one connection. Other proprietary systems have been created to offer high channel count low latency connections. These have proved popular in the music touring world and some broadcast set-ups. Meanwhile networked audio started with protocols like CobraNet, and now we have Dante, RAVENNA and others. To the uninformed these do the same thing, just move audio from A to B. But the difference is that these protocols are not point-to-point and work across IT networks, allowing you to route channels in almost any combination. Alongside this is AVB, an IEEE standards based technology that could stand on its own or underpin many of the existing networked audio protocols. Current industry technologies Lets look in more detail at the technologies available, the problems they solve, and the pitfalls you may encounter.

2 Audio networking Dante Dante is currently one of the most popular audio networking protocols. Manufacturers can implement Dante into their products by purchasing a card that slots into their product. The business model here is the sale of hardware. End users can enable their computers to send and receive Dante through a low cost software purchase. Dante products are shipped by more than 100 manufacturers and over 750 products are available on the market. Dante is simple to use and connecting together a network of audio devices will normally work first time. RAVENNA RAVENNA is a network audio protocol that was originally designed for the broadcast market. Invented by ALC NetworX, it has been adopted by nearly 50 manufacturers. Manufacturers can include RAVENNA in their products using a variety of means. Currently three vendors sell hardware in the same way that Audinate does for Dante. Additionally you can license the code and receive support and naming rights from ALC NetworX. Since RAVENNA is completely open it is even possible to engineer it yourself, if you have sufficient knowledge. There are also a number of both free and paid for software solutions for end users to install into their computers. RAVENNA offers an extremely flexible solution. You can send audio at different bit rates, sample frequencies, and modify very many aspects of how the data is packetized into the network. This flexibility comes at a cost. RAVENNA is not as simple to implement as Dante. You normally need to employ people with good networking skills to ensure it is set up properly. The only current exception to this is when you are using a system with components from only one manufacturer. AES67 AES67 is not an audio networking protocol, although some would debate that statement. Strictly speaking AES67 is an agreement that allows different audio networking protocols to pass audio between each other. AES67 uses widely

3 used standard IT protocols to achieve this. For example, using AES67, an item of Dante equipment can pass audio to a RAVENNA device. There are a number of protocols that are AES67 compatible and it is likely that this compatibility will spread further, not just to audio products but for the audio element of video products too. Indeed the AIMS consortium of audio, video and IT manufacturers is developing an industry standard for networked video. This includes SMPTE , a standard for transport of high bit rate media signals over IP networks, for which it has been agreed that the audio element shall be AES67. In order to benefit from AES67 you need to have a mother protocol installed in your product such as RAVENNA or Dante. In the case of RAVENNA, AES67 compatibility exists natively as the two technologies were really developed together. For Dante, firmware upgrades for some products are starting to appear in late AES67 upgrades are not possible for all Dante solutions. AES67 was deliberately designed to be a stripped down standard in order to make it as compatible as possible and in order to gain broad acceptance. However, this has meant that it is not necessarily instantly useable. In particular two technical elements are missing. The first element is a means of finding devices on the network so you know that you can connect to them and pass audio between them. This is known as Discovery. There are a number of different methods to discover devices on a network. This is akin to WhatsApp or Skype, where you can see who is available to communicate with. Unfortunately, different audio protocol manufacturers use different discovery methods and each has particular advantages and disadvantages. Consequently, if you use one of their recommended methods then you are really locking yourself into the features of their native protocol, which defeats the point of trying to use AES67 in the first place. The second element is connection management AES67 has no tool for setting up how audio is patched between devices. For AES67 to be widely adopted then these problems need to be addressed. System control There is no standard control system for the audio industry. Intercommunication between equipment is poor in comparison to other industries products. If you want to control audio equipment there are a number of third party control systems, including Crestron and AMX, that can give end users a clean, locked down user experience often with the use of touch screen controllers.

4 A couple of audio signal processors allow 3 rd party code to control other items. QSC s Q-SYS and Peavey s Nion platform both already have tens, and in the case of the latter, more than 120 plug-ins to control and monitor other equipment. The Open Control Architecture Alliance (OCA) was set up to provide a standard for system control and connection management for audio and AV systems. This standard is now called AES70 and it is in the very early stages of adoption into shipping products. So what next? What has been missing from all these technologies has been any level of coherence. It s also important to note that networked audio is still used in less than 10% of all professional audio projects. The vast majority of professional audio systems are still using analogue connections. Furthermore, a recent survey found that around 70% of networked audio projects were using a separate audio network. These networks don t touch the building network carrying all the data. You have to ask the question why? Why are most systems primarily analogue, even though almost every item will be digital inside? Why are most audio networks sitting there on their own? Why is the audio industry not really integrating with the rest of the IT world? There is no single answer but it boils down to the fact that adoption of this technology is still too difficult to do. What do we mean by difficult? In the case of Dante, it is easy to use on its own, but this solution often won t work well amongst other network traffic, and you need additional skills to implement it well across very large networks. RAVENNA is not trivial to implement but very malleable and can work in complex mixed-use networks. Scale isn t a problem either and it has even been used between cities. For other people the problem is more fundamental: networked audio just seems more confusing for them in comparison to analogue audio. In a world of smartphones this really shouldn t be the case. It is just that the audio industry hasn t created the tools to enable systems to be set up very easily. The reason for this is some of the mechanisms with which to achieve real ease of use and true interoperability have been missing.

5 What are we controlling? Earlier we mentioned how cheap audio processing has become, but that doesn t necessarily mean that it should be put into every audio product. The biggest challenge here is when you have many I/O nodes, each offering audio processing, how do you manage all these elements? Even a small, networked audio system could have twenty nodes, each with many audio channels, and each of these with dozens of settings and parameters that can be changed. How do you know what is really going on? How do you retain control? Existing control systems concern themselves with changing parameters on remote devices. Often this is as simple as a memory or preset change. Some systems also allow you to monitor the status of a device. In the definition of OCA it says that it provides a standard for system control and connection management. This is important because it doesn t just control devices but it allows you to control the networked audio itself. Audinate have a software tool called Dante Controller that lets you route the audio streams between devices but this is generally something that is set up once and then left. If you wish to do frequent re-routing of audio, you send dozens of channels to a digital signal processor that contains an audio matrix. This then resends the incoming audio streams to the appropriate outputs as required. Configurations for different scenarios can be stored and recalled, and the switching between different settings is instant and seamless.

6 Conventional Audio Routing is managed through a signal processor AES67 allows you to use the network itself as an audio matrix Rather than using a processor to carry out that switching, it would be great if you could just re-route what you need using the network itself. The subsequent mixing and signal processing can then be done at the receiving device. Dante networking technology doesn t offer instant switching of audio channels, and neither was their controller designed to be used for that purpose. Traditionally you need to set up networked audio connections using third party software

7 RAVENNA and AES67 technology does allow for near instantaneous switching of audio signals on the network. This can take away the burden of needing a central processor to do all this. Instead of a big central roundabout, imagine a network of roads where each car knows where they need to go. AES70 was designed not only to control devices. It can be used to control networked connections too. Therefore the mechanism exists for AES70 to control AES67 audio streams. Devices can patch audio to each other without the need of a centralized control tool. Although you could also use one as well. Devices will be able to resolve connections to each other without the need of a software control program Discovering the solution AES70 contains robust mechanisms for device discovery regardless of what audio networking protocol is being used. This eliminates any squabbling over which audio protocol has the best discovery method, as AES70 sits above all that. AES67 allows different audio networking protocols to pass audio between each other AES70 compliant devices advertise their presence on the network. This offers flexibility in audio set up where devices may appear and disappear from the network subject to how the system is being used. Furthermore, AES70 enabled devices can advertise their services, so you can see what set of audio tools are available for you to use.

8 The solution AudioLAN 2.0 combines AES67 and AES70 into one coherent technology. It is not just two separate streams of data, one for audio and one for control. The AES70 element actually controls what the AES67 streams are doing. In addition AES70 allows remote control of equipment. AES70 was designed to be very scalable, from two devices to thousands. It will work across very large networks in the same way as it does across one single switch. AES70 provides the network intelligence to allow it to modify the audio streaming to suit the requirements of each and every network. Benefits for the user Whenever a new technology is announced some inevitable questions are asked what does it mean for me? and when will it be available? AudioLan 2.0 will be a firmware upgrade in all Archwave equipped products over the coming months. Bosch will start to implement it into their products. BENEFITS Audio transport Device control and monitoring Connection management Based on existing standards Network intelligence Users get access to a Universal audio transport that not only allows data-streams between its own devices but also between AES67 compliant nodes from manufacturers It Piggybacks on the developments in the IT industry. Due to the sheer volume of components being used in the IT industry, AES67/RAVENNA can fully benefit from the developments and price-decreases of IT components as they are both build on standards that are commonly used in the IT industry. IT networking is here to stay. There already is a massive network infrastructure all over the world based on IT standards. Every office, home, building is using the

9 same technologies, so technologies will improve and bandwidth will broaden,but the basic concepts stay the same. Products based on AES67/RAVENNA will remain compatible for year to come and will fully benefit of the future improvements of these technologies. AES67 and AES70 are backed by major players of this industry that all hope to gain from interoperability. Since anyone can develop products for AES67 and AES70, there is no risk of being stuck with a technology if a company fails. If a supplier fails, someone else will take over, the standards continue. All of this makes it a safer long-term investment. Finally this gives users freedom of choice for products and they are not being bound to a specific manufacturer or protocol. AES67 and AES70 will be the new standard XLR for audio. Together they become an intelligent and formidable solution.