A look at the infrastructure and hardware behind superb digital audio networks for churches.
For architects, designers, consultants and AVL integrators, proper design and configuration of the local area network (LAN) is an increasingly vital consideration in any new church construction or worship space overhaul. With AVL technologies migrating onto networks at breakneck speed, the LAN has become the central nervous system of the worship experience.
That means, when the LAN is humming smoothly, the worship can be extended and enhanced in creative new ways. But if the LAN is not sufficiently robust or becomes overloaded, we can have a “nervous breakdown” of digital AVL technologies.
For some solid advice on how to design and configure church LANs, we enlisted the help of three industry experts, to be introduced as we proceed. But first, let’s recap the basics.Network Hardware Fundamentals
On one level, the infrastructure of a church LAN is simple, with two components:
• Cables – These carry the digitized information and can be either copper (e.g., Cat-6) or fiber optic.
• Switches – These devices sort out all the Ethernet data packets and make sure each gets to its proper destination, preferably in its designated time window.
EXTRON | Dante-equipped Extron DMP 128 Plus AT models provide scalability with a built-in, four-port Gigbit switch for creating larger audio matrixes over a LAN.
In media systems, the network connects other devices—called endpoints—that produce or use the network traffic: audio and video signals and control data. Examples include everything from computers, mixing consoles and wireless microphone systems to video streaming devices and lighting controllers.
In converged networks, the same switches and cables also can handle Internet connectivity, security systems, HVAC controls, telephone systems—you name it. How do you make sure that your network will handle it all, glitch-free, for a decade or more?
Realistically, it’s likely that some switches, routers and endpoints will have to be upgraded within a 10-year span. But as these components are relatively accessible, labor costs will be minimal. The same cannot be said of cabling, particularly when enclosed in conduit. So that’s our first order of business.
FOCUSRITE | RedNet is Focusrite’s flagship range of modular Ethernet-networked audio interfaces that harnesses the power of Audinate’s Dante digital audio networking system.
All of the newer audio production and video streaming platforms rely on a Gigabit Ethernet infrastructure, which means all cabling must conform to Gigabit specification.
“Cat-5e is the minimum, but you might want to move up to Cat-6 in environments where you expect heavy RFI or EMI interference,” cautions Matt Pliskin, RedNet technical sales engineer at Focusrite in the Los Angeles area.
Patrick Killianey, network applications engineer at Yamaha Professional Audio Systems in Orange County, Calif., advises moving up in any case. “There isn’t a huge price difference between Cat-5e and Cat-6, so consider making that your minimum. And for conduit pulls, I’d even consider Cat-6a for any future enhancements with 10 gigabit networks.”
Killianey also notes the importance of cable types within the categories. “Stranded and unshielded cable is often preferable for shorter patch cords, as it bends more easily. But it also has more electrical resistance in the wire. For permanent cable pulls, solid core shielded (STP) is best, and I would make sure it is all plenum rated. Even if your cable pulls don’t require it, I would use it to make inspections go quicker.”
It is possible to balance wider campus network access with the isolation needed to ensure glitch-free AVL systems for worship.
Add Fiber to Your Network Diet?
To keep your infrastructure as future-friendly as possible, our experts recommend pulling fiber optic cable for all mid-sized and larger church installations.
“If you have long cable runs with high interference at the extreme ends, then fiber optic is the way to go,” says Pliskin. “It’s very easy to implement as most managed switches with more than 10 ports will have and SFP slot [also called mini-GBIC] for connecting via fiber.”
Fiber optic infrastructure is also advisable if your production video is migrating onto the network, says Joe da Silva, director of product marketing at Extron in Orange County, Calif. “When you get into video distribution, everybody is now talking about deploying 4K video, and when you look at the data rates that requires, they can get high very quickly. At that point fiber optics is a far better approach.”
This approach is ultimately more cost effective, says da Silva. “It’s really much cheaper to do all your cabling the first time, during new construction. Going back and reinstalling can be expensive. Depending on the jurisdiction, you might get an inspector who wants abandoned old cable removed, whereas new cable can just be tagged for future use. And fiber cabling is just pennies per foot, so putting in a few strands is a wise investment.”
DIGICO | The D2-Rack is the latest addition to the range of high sample-rate racks. The compact 9U D2 rack has a fixed format 48 inputs with 16 outputs fitted as standard.
Reliable AVL networks also depend heavily on proper installation of switches and endpoints, coupled with appropriate cable terminations.
“The first thing is to keep it as simple as possible,” emphasizes Killianey. “When placing switches near the stage or FOH mix, make sure your installations are sturdy and robust. For example, mount all switches well recessed and in a protected position. And wherever you have cables that can be snagged or tripped over, it’s best to have network terminations on Neutrik’s Ethercon connectors. Try to limit unprotected plastic RJ45 connectors to out-of-the-way equipment rooms.”Managing Your Switches
Gigabit networks switches are a commodity item these days, which means consumer grade models can be had for well under $25. But our experts agree that a “best buy” switch is not your best bet for critical media systems.
“Do not get an unmanaged switch,” Killianey warns. “It’s fine for your home studio, but not if your worship is relying on it. Also, by the time you get into managed switches it so happens that the manufacturers are spending more money on the basic internal structure for faster speed and lower latency.”
A good managed switch is necessary to allow configuration for the needs of real-time production AV systems, according to Pliskin. “If you are putting mixed traffic on your network, then a switch must offer QoS—quality of service—to make sure all the clocking data for digital audio is getting through with top priority. Also, you need to be able to turn off Energy Efficient Ethernet as in some cases it can cause synchronization issues. These managed features make sure everything plays together nicely.”
A consensus choice of two panelists for a “go-to” switch is Cisco Systems’ SG 200 and SG 300 Series, tested and approved by multiple AVL suppliers. “Reliability and capacity are much improved compared to entry level switches,” notes Killianey. “Others may have similar capabilities, but it’s up to the user to make sure their alternate choice has all the needed features and capabilities.”
In some situations, however, the IT department or consultant may specify another switch for use in common networks. “We’ve found that, in many commercial environments, the company IT departments will have their own preferences,” says da Silva, “and this can happen in large churches as well. We use a lot of Cisco products, but others may use HP or Juniper. We didn’t want to get into a position of implying Extron systems work with only a certain manufacturer’s switches, so we’ve qualified our systems for compatibility with most of the top tier switches.”
Isolated or Converged?
YAMAHA | The SWP1 from Yamaha is a purpose-built switch for professional audio applications, with enterprise-grade, locking connectors, redundant power supplies, a rugged chassis, and Dante-readiness.
Most production-oriented networked audio systems, at least to this point, rely on a dedicated and isolated hardware network, one that uses its own cables and switches exclusively. In some cases a redundant backup network is added, although often set up on a virtual local area network (VLAN) sharing the same hardware components. And endpoint systems, such as Digico’s digital audio mixers, avoid switched networks for their internal stage-to-FOH “backbone,” instead instead employing point-to-point technologies like MADI on copper or Optocore on fiber.
Lately, however, the trend has been toward placing all network traffic—including production audio and video streaming—on a single, campus-wide converged network, with all applications sharing all the same cabling and switches. A good idea, or a situation to be avoided?
Killianey says that it is possible to enjoy the flexibility of a wider switched network along with fail-safe reliability. “Having dedicated network hardware reduces the chance of problems, and makes troubleshooting easier if they do crop up,” he notes. “However, integrating internet can be as simple as connecting a home router to the LAN port on your audio network, and connecting the WAN [wide area network] port to the cable modem or campus network. That way, you can have internet access for downloading software and firmware updates, and then disconnect during worship and events just to be safe.”Managing IT Creep
Some people in the world of church design have been caught off guard by the explosion of networking technologies in AVL systems for worship. How did this happen? It seems just yesterday that computer networks were reserved for the office manager and administrative pastor, adequate to keep the books in order and the e-mails flowing in and out. Now we have to worry—theoretically—that worship audio may become distorted if there is too much activity in the security cameras.
However, with planning and foresight, this is not a realistic concern. It is possible to balance wider campus network access with the isolation needed to ensure glitch-free AVL systems for worship. Some basic re-education is called for, cautions Pliskin, but it’s not full-blown rocket science.
“A deep level of IT knowledge is not necessary except for the very largest installations,” Killianey says, “and typically in those scenarios there will be a team of IT professionals involved and you will have to entrust them with that side of things. It is advisable to remind them of the unique demands of live AV systems, particularly regarding switches, but they should have no trouble conforming to your requirements. Don’t worry if your IT knowledge base is fuzzy around the edges. It doesn’t have to be that complicated.”