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Aviom’s ProNet 6416 is a versatile output module employing the latest iteration of the widely adopted A-Net protocol.
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Yamaha’s CL and QL Series mixing consoles now can be ordered with Dante cards that are fully compliant with the new AES67 interoperability standards.
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Riedel’s RockNet 300 network carries up to 160 channels of high resolution audio with sampling rates of up to 96 kHz.
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Shure - ULX-D: A professional digital system operating in the UHF band, with several frequency-agile 64-MHz bands available between 470 - 932 MHz; scanning with automatic or manual channel selection; wide audio bandwidth with 24-bit/48-kHz sampling rate; latency < 2.9 ms; variable transmitter power levels; encryption; analog and digital outputs; Ethernet for computer control; 1RU with two receiver channels.
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The high-speed SoundGrid network from Waves is the backbone for the company’s new eMotion LV-1 modular digital mixing system.
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Riedel’s RockNet 300 network carries up to 160 channels of high resolution audio with sampling rates of up to 96 kHz.
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Roland offers complete digital snake systems for its consoles based on the company’s proprietary REAC networking protocol.
It's enough to make your eyes glaze over. When reading about audio networking, you wade into an alphabet soup of obscure terminology: isochronous, TCP/IP, OSI model, spanning tree, IEEE 1722.1, AES67, QoS and DiffServ, for example. Even ATM is in there, but here it refers to asynchronous transfer mode, not where you go to get cash.
Welcome to the brave new world of audio networking, and—like it or not—it's here to stay. Yes, there are new concepts you really need to know. And you need to be familiar with the main proprietary and open-source networking options commonly used in worship sound applications.
Fortunately, if you're a church tech who is simply using and maintaining systems, there's even more stuff you don't need to know. At least not yet. So let's start with …
What you Need to Know Now
Basic differences between networked and point-to-point digital systems – Audio networks carry digital audio signals from one place to another, but not in quite the same way as dedicated connections like AES3 (formerly AES/EBU) and MADI. In point-to-point systems, as the name implies, the signal goes from one device to another as determined by the connection. It is not switchable or routable. Multiple channels of audio may be multiplexed onto a single connection (as with MADI), but the channels are not separated into discrete digital packets and addressed individually, as in a switchable network.
Also, nearly all audio networks (except a few that use fiber optics exclusively) use common Ethernet connectors and cabling, including Cat-5/5e/6 cables and RJ45 network plugs and jacks. Networks that are switchable use standard networking hardware, though not all switches and routers will work satisfactorily with all audio networks.
Differences between built-in or self-configuring vs. user-configurable networks – Many proprietary, dedicated-purpose audio networks are plug-and-play, making them essentially idiot-proof. As long as you have the right kind of cables, you simply plug in all the units as directed and fire up the system. Aviom’s A-Net, used primarily in the company’s personal monitoring systems, is a pioneering example of this approach.
In between we have proprietary networks that can support multiple devices and applications. Some will require set-up and configuration, particularly when switches or routers are inserted into the network. But because these networks are purpose-built to work within a particular manufacturer’s domain, they are nearly bulletproof and at least have a single source of support. Roland’s REAC and QSC’s Q-LAN fall into this group.
Finally, we have the more flexible, open-ended networks, either proprietary third-party like Dante or open-source like AVB. Although some devices or applications will apply these protocols in a basic, self-configuring mode, in most cases some relatively sophisticated set-up and configuration will be required—at least to get up and running.
How much latency to expect and how this will affect your applications – Latency is another word for signal delay, and all networks introduce latency to some degree. In most cases it will be minimal—a few milliseconds at most—but you do need to know how much latency you will experience and under what circumstances. Even with the same network protocol, the amount of latency often will vary with the network configuration, most notably with the number of “hops” between various devices and intervening switches or routers.
In some situations, such as distribution of audio to other rooms on campus, latency is not an issue. In others, such as in-ear monitoring, higher levels of latency can be audibly annoying to sensitive ears. Although the network latency alone is not likely to be a problem, when combined with the latency introduced by other digital processing (most notably A-D and D-A conversions) it could rise above the noticeable threshold.
The level of audio quality and number of channels supported – Most of the newer audio networks, particularly those based on gigabit Ethernet, will support dozens if not hundreds of channels, and with 24-bit resolution at sampling rates of up to 192 kHz. But there can be tradeoffs. If the system is based on the near-obsolete Fast Ethernet (100 Mbit/s), then there can be a tradeoff between number of channels available and the sampling rate limit. This could be an issue if you are doing high-resolution recording of the worship music.
Cable types and maximum lengths – This can be tricky, because superficially the cables may look the same. But newer networks based on gigabit Ethernet will require Cat-5e as a minimum and, preferably, Cat-6 cable.
The rule of thumb for networking protocols based on Ethernet is a max. distance of 100 meters between "hops."
The rule of thumb for networking protocols based on Ethernet is a maximum distance of 100 meters between “hops”—either a sending/receiving unit or a switch/router. Some proprietary protocols claim to extend the maximum distance to 150 meters or more.
Who to call for support – If your network uses a proprietary protocol built into a single-manufacturer system, then it’s a no brainer. The same applies if you have a system where the network protocol and the hardware come from the same source, such as Riedel’s RockNet. If you have a third-party protocol that is licensed to different hardware suppliers, and you have two or more different hardware suppliers in your system, then you may have to isolate your problem before seeking assistance. This is particularly true if you have intervening switches or routers that could be the source of trouble.
The same would apply if the hardware components are connected by an open source network protocol, although it is highly likely in both situations that the maker of a primary component (mixing console or DSP unit) would guide you toward a solution.
Major Players in the Church Market
A Wikipedia page entitled “Comparison of audio network protocols” lists no fewer than 20 different technologies as currently available. However, many have distinct applications not relevant here, such as in broadcast studios or for distributed audio in large facilities like hotels and convention centers. Here, we’ll look only at those appropriate for audio production in a worship setting.
Built-in Proprietary Networks
The first group I’d call “console-centric” networks, as they were designed primarily to connect a company’s mixing consoles to stage boxes, personal monitoring systems and/or recording devices. Here we find Allen & Heath’s ACE (Audio Control over Ethernet) which provides up to 64 bi-directional channels and can be integrated into A&H’s iLive and GLD Series consoles. Roland’s REAC (Roland Ethernet Audio Communication) interconnects the company’s digital mixers, hardware digital recorder and personal monitoring systems with a 40 x 40 channel link with low-latency and 24-bit/96 kHz resolution. Also in this category is Behringer’s Ultranet which links the company’s mixing consoles to Behringer’s own P16 personal monitoring systems as well as IQ Series powered loudspeakers.
Waves, a dominant provider of signal processing plug-ins, originally developed its SoundGrid network to connect outboard DSP servers to digital consoles. More recently it has been applied to serve as the network backbone of Waves’ new eMotion LV1 modular digital mixing system. The DigiGrid system from Digico bridges MADI-based systems to Waves Soundgrid.
Aviom’s Pro64 is the latest iteration of widely accepted networked audio systems that are ubiquitous in church personal monitoring systems. The Pro64 Series comprises a full range of modules for integrating into comprehensive, campus-wide audio networks.
Q-LAN by QSC is a powerful and flexible networking protocol that has found wide acceptance across a broad range of high-level AV install applications. However, as it is reserved for use within QSC’s own Q-Sys platform for distribution, signal processing and amplification, it has found limited use on the “front end” production side of worship sound.
Third party proprietary protocols and systems I’ve grouped these networks together because the companies involved are focused solely on network connectivity. They may or may not make the accompanying hardware, but they don’t make mixing consoles, DSP units or amplifiers.
Unquestionably, Dante has become the 300-pound gorilla in the room. Because its Australian-based creator, Audinate, had no stake in any particular hardware, the company decided to license the technology to anybody qualified to implement and support it. Because Dante offers ample channel capacity, high-resolution audio, and could be implemented with properly selected and configured off-the-shelf networking hardware, it grew to become the dominant player, with over 160 manufacturers now offering connection via Dante. In fact, several audio manufacturers have developed complete Dante-based connectivity packages, most notably the Rednet Series from Focusrite. Independent developers of personal monitoring systems, such as Digital Audio Labs, rely on Dante as their networking component.
Germany’s Riedel specializes in integrated AV connectivity systems at all levels, and their RockNet system is appropriate for a broad range of worship applications. Like Aviom’s A-Net, it works at the physical layer of Ethernet for simplicity and tour-tough reliability.
The pioneering CobraNet from Cirrus Logic is still a factor, though more so in audio distribution than in production applications. Other players in this category include Optocore’s SANE (Synchronous Audio Network + Ethernet) fiber optic networks and EtherSound by DigiGram.
Open source networking
The following protocols and standards don’t belong to a particular company and therefore are open for use to all with no licensing fees.
Two standards developed by the Audio Engineering Society are of note. The first, AES-50, uses standard Ethernet wiring but is not a true switched network. The protocol definition is used as the basis of the Super MAC and HyperMAC connectivity used in Midas digital consoles and Klark Teknik signal processing.
The AES-67 standard is an umbrella protocol that maps out interoperability for various audio-over-IP platforms. Dante, Q-LAN and Ravenna platforms have pledged to comply with the new standard. It’s catching on fast, with companies like Yamaha jumping on board.
And finally, the long-awaited AVB (Audio-Video Bridging) protocol is fully in place and widely adopted by a number of major players (Meyer Sound, Biamp Systems, and PreSonus, to name a few), with interoperability certified by the AVnu Alliance.
What you DON'T need to know
If you’re a church tech just getting your feet wet, the above will do for now. But realize that in years to come you’ll need to dive in considerably deeper.
Be prepared to learn the OSI model and its layers. This is the cornerstone of networking, and you need to understand it to track how the packets of data find their way around and manage (we hope) to arrive on time and in sync.
From there you can delve into the relative strengths and weaknesses of systems based on different OSI layers: layer 1, layer 2, layer 3 and layer 2/3 hybrid networks. Lower layers often benefit from simplicity and reliability while higher layers provide more flexibility and control options.
From there you can master the intricacies of TCP/IP, which stands for Transport Control Protocol/Internet Protocol. It defines the rules for packaging, addressing and routing data around the network, either locally on a LAN or over the Internet.
If you intend to configure your own networks, you’ll need to understand the various topologies—ring, star, daisy chain, etc. —along with their advantages and limitations in different applications.
At some point you’ll need to understand convergence, with audio and video content sharing networks with other data. That entails a thorough knowledge of Time Sensitive Networking (TSN).
And along the way, you’ll have to learn the meaning behind all the arcane terms listed at the beginning of this story. And many more. But all in good time.
