Plugging In - Or Plugging Up – Your Stage?

(for more about Rob, click here)

In my many encounters with church building committees over the years, there’s often an overwhelming theme: build a room that can be utilized for a multitude of functions including worship, special events, dinners, receptions, ….
the list goes on.

It’s a discussion of compromise and of thinking to the future. For example, wouldn’t it have been nice - 25 years ago - if the building committee had considered that there might be need of more than a “roamer mic” and organ at the platform?

Of course, caution should be taken when addressing the subject, because we may be talking to some of the same committee members who helped make that initial decision.

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That said, the committee members may also remember the subsequent funding needed for more conduit and floor boxes for the stage, including cutting up the concrete floor to get this done.

Meanwhile, the sound crew regularly trips over a bundle of mic cables and faces the unnerving challenge of tracing a bad cable to the soloist five minutes before the service begins. All of it points to the fact that we need to be thinking about cabling and connectivity, as it will affect future generations, perhaps even long after we’re gone.

What can we reasonably estimate to happen in the next 15, 25 or even 50 years? We start by listing out what currently will – and likely could - be needed on stage. Such a list may include singers, preachers, pulpits, baptismal, communion table, drums, guitars, piano, organ, bass, strings, brass…

Next, the question becomes location. Can we really anticipate the exact position of each of these items in the years to come?

One answer is yes - we can anticipate positioning because we will control it with a stage design. This is a popular option among larger churches, but can be very unpractical for the small-to-medium church. This approach, basically, means designing the stage with fixed choir, piano, organ, orchestra, monitor mixing, and other positions, and the result is superior sound quality in addition to consistent entrance and exit to various areas of the stage.

The other answer is no – we can’t possibly anticipate accurately. In reality, this is the case in the majority of situations. But let’s back up. When discussing systems, I always have two perspectives: musician and technical (or “techie”).

The musician side of me wants a stage free of chords, with plenty of space to interact with other musicians and the congregation. And I want the ability to plug in any instrument at any realistic place on stage. For example, if the drummer’s in the back, the technicians should be able to mic all of the drums if needed. The techie side of me wants easy cable runs, clean signal, and happy musicians.

The easy answser: provide a ton of wire and conduit from that stage to the control area(s). Not just to the mixing console, but also to video rooms, studios, etc. This is not to say that you should have 400 mic lines running all over the place. (Who’s to say what type of mic lines will be standard in the next 5-10 years anyway?)

But build in the flexibility to run individual lines, snakes, fiber, data or whatever else may be encountered now and in the future. Make sure there are several conduits; it’s cheap to do now, very expensive later.

Note that not all wires can be next to each other. Some electrical contractors may ask if it’s OK to us PVC instead of steel conduit, and the answer is to use steel whenever possible. Steel offers a magnetic shielding from electrical wiring. (PVC does not.) Using steel goes a long way to eliminating nasty buzzes and hums. However, if the budget dictates PVC, make sure that it’s located as far away as possible from electrical and other wiring. And, always keep separate mic, speaker, video, data, and whatever other wires.

Floor boxes are your friends, and wall panels and plates are a welcome substitute for floor boxes. My recommendation has been boxes/panels placed strategically around the perimeter of the stage. Install as many as possible, but keep them invisible from the seating areas. Also remember that it’s important to be able to get cables outside of the “performance area” as quickly as possible.

Now, let’s fill these floor boxes/plates. Each box contains 6-12 jacks in it. Keep things organized with simple numbering: Box A jacks are numbers 1-12, Box B is 13-24, and so on. You can have literally hundreds of sound system inputs at the stage, divided between the boxes, without being excessive and without confusion. Jacks can accommodate a variety of inputs and outputs for other systems/uses as well, usch as AC power, video, data, etc.

Drop snakes can also serve useful purposes. In essence, a drop snake can take the inputs of each box and put them at a new location. A drop snake simply takes the inputs in each box and links them to a new location on stage.

With a multipin connector-style snake, you place a multipin connector in each floor box that duplicates the input of that box. (A mulitpin connector puts all of these lines into one connection, locking into place via a connector of the opposite “gender”.) Thus, all lines go through a single snake to a box or “ran” on the other end, which breaks out each line individually again.

This approach makes each input available at the box, and at the end of the snake. But it’s crucial never plug into both the input of the box and the same input on the snake. BAD THINGS WILL HAPPEN. The goal is to gain the option of connecting a mic cable to the floor box for input - OR - running the mic cable to the end of the snake.

An option to multipin snakes is fan-to-box snakes. These plug into each line individually, so the snake jacks coincide with the floor box jacks. This approach is more time consuming but much safer. All in all, either approach saves time and cleans up the stage. (We generally snakes ranging in 15ft – 75ft in length.)

All right, let’s say we’ve got all of these items plugged in at the stage, at various floor box/wall panel locations. For example, drums are on channels 9-15, vocals on 74-82, lead guitar on 4 and bass on 63. We’re using a 32-input mixing console posted at front of house.

Wait a minute – our math doesn’t add up. More inputs on stage than at the console! This is where we encounter patch bays, which allow the sound tech to simply take any input on stage and assign it to any channel on the console via a short patch cable. Think of an old-time telephone switchboard in terms of look and function.

Patch bays can be our best friend, but they can also present problems. First, a quality patch bay costs $1,000. And even at that rather lofty price point, they can still be one of the first things to go bad within a system.

The biggest way to avoid patch bay problems is proper installation, and as a result, we recommend a qualified contractor to do this. It’s a detailed, labor intensive process, which adds even more to the cost, but without proper installation you’re just setting up a disaster.

Another option is the “poor man’s patch bay” - a snake box, linked via its snake to the house console. The box, meanwhile, is usually mounted at a backstage location, ready to accept inputs running from the stage. You then simply take stage inputs and plug them into the box as needed – easy and flexible switching of inputs.

Also keep in mind that while a 32-input console may be in use now, there may come a day when it makes sense to expand to a 48-input board. Therefore, use a snake big enough to accommodate this growth in inputs, simply covering the extra inputs until they might be needed. One note is to be cautious – don’t allow anyone the opportunity to plug into channel 32 on the snake box if console channel 32 is being used for a CD player.

Some of this may sound pretty basic, but the issues covered here come up with every project, time and again. You may be using a 32 input board now but may want a 48 input board soon. Run a snake big enough for growth and place a box with more inputs than you currently need. Simply cover up the extra inputs and indicate they are not to be used. Also, don’t forget about those wireless mics, cd players and other items that may occupy channels on the board. Don’t provide someone the opportunity to plug into channel 32 on the snake box if channel 32 on the board is the CD player.

All of this may seem to be pretty basic stuff, but it’s taken many people (myself included) three or more times of doing things wrong to get them. While a qualified AV contractor should be able to accomplish these techniques, it’s important to understand the concepts and to be able to raise questions and propose approaches that work best for your situation – now, and in the future.

Click here for Part 2

Rob Stam can be reached at rstam@spectrumdesigngroup.com