Once upon a time, live sound was much simpler than it is now. We put mics in front of our vocalists, plugged their instruments into DIs, fed the signal via snake to our mixer, and mixed the signals for our congregation and musicians. Nice, simple, analog signal flow — no crazy wireless or digital signals flowing everywhere over Ethernet cables. It was simple, it was easier… but nowhere near as good as it is today. Yes, we have to deal with digital networks and the increasingly complex world of wireless (which is becoming more complicated all the time), but the benefits are worth every bit of struggle we face. This month, let’s look at ways of optimizing our wireless systems. Most churches are using at least a little wireless; some are using a metric ton of it — and it’s a major, integral part of many church systems, so it’s important to get it correct.
Rule #1
Right out of the gate, don’t cheap out. When replacing traditional monitors with IEMs, it can be hard to overcome the institutional and individual resistance to change. If our seasoned musicians and vocalists have adopted the “if it ain’t broke don’t fix it” stance, we timidly present the idea of IEMs, and just dip our big toe in the water — buying a cheap system in case the old-timers decide they hate it. However, if they were already predisposed to hate it, and the system is cheap, it’s not going to work well: The old-timers are REALLY going to hate it and now have a legitimate rationale from which to argue against the new paradigm. This holds true not only for the introduction of IEMs, but for the introduction of anything new, including wireless systems. Trash gear not only fails to accomplish our goals, but it also sours our people to the notion of progress in general. It’s worth budgeting for good stuff and integrating it properly. And we’re not just trying to convince our creatives that it’s great — we’re also seeking to win over our tech folks as well. I’ve seen many seasoned engineers resist wireless because “what we got already works fine.” It is worth noting, however, that in some cases, we are better off to keep hard wiring and limit the use of wireless to only the applications for which it actually makes sense.
On that note, I would also point out that the purpose of wireless is to free our musicians and vocalists to move about the platform — NOT to get all of our signals to front of house. Wireless is not 100% reliable. Heck — wires aren’t even 100% reliable. Wireless is reliable enough to allow our musicians to move freely around the platform, but it’s best to only use wireless for applications intended for exactly this purpose. This actually plays right into another little piece of advice — get the transmitters and receivers close to each other. It definitely makes more sense to use hard wires to move signal between front of house and the platform, while using wireless to move signal between performers and the wings or up stage. With a few exceptions, RF works better when the transmitter and receiver are closer together. At the very least, our signal will be more solid over the shorter distance to the wings or upstage than it would be to front of house (unless you have an atypical situation in which the physical distance to front of house is shorter).
Line of sight between antennas is also desirable, and we will almost certainly have less control over that aspect if antennas have an ocean of passionate parishioners between transmitter and receiver antennas.
It’s also a good idea to choose the right antennas. There are a couple of attributes I’d recommend for consideration. The first one might sound a little counterintuitive: Use a less sensitive antenna on the receiver side. “Why would I want less sensitivity?” you might ask. If there’s a whole lot of RF in your space (generated by you or not), you won’t want to pull all of it in. A slightly less sensitive antenna has the de facto effect of rejecting the signals you don’t want, which is a good thing. The other attribute (which immediately makes more sense at first blush) is to use directional antennas. If we can direct RF energy more precisely toward where we want it to go, we can reduce the amount of power we need to radiate, and any time we can reduce the amount of RF soup in our space, that’s a win.
Back to The Money Issue
We earlier visited the notion of budgeting enough money to get solid gear that works well. In relation to that, non-diversity systems are almost universally less expensive than diversity systems, but diversity systems almost universally deliver a more consistent and higher-quality signal. Similarly, budget systems may not offer as many available frequencies. It might seem as if we can just find the frequencies that work, lock ‘em in, and we’ll be good to go, right? Unfortunately, our situation can change, and the frequencies that worked yesterday may no longer do the trick today, for whatever reason. If so, we need to have backup frequencies available. A higher quality system can give us the additional frequencies that we may occasionally need. On a similar note, it’s also a good idea to be prepared for catastrophic wireless failures — don’t pack those cables too far away!
Wireless frequency coordination is essential to optimization. We should do so often, particularly if we have a lot of our own wireless running in the space, or if there’s a lot of external RF with which to contend. This is typically a bigger issue in larger population centers, with the air space crowded by hundreds of RF sources. And as we mentioned earlier, the frequencies we used last Sunday may not work for us this Sunday. I won’t say weekly coordination is a necessity, but it’s a good idea to revisit this on a regular basis — perhaps monthly if there’s a lot of RF crowding, or quarterly in locations with fewer transmitters.
Engage in best practices concerning batteries. The no-brainer aspect is to ensure fresh batteries, topped off to the brim, are installed into our transmitters and receivers right before the beginning of services. Unfortunately, this doesn’t always happen, usually when one hand doesn’t know what the other one is doing — “I thought he put fresh batteries in the pastor’s transmitter.” Sometimes, however, it’s a matter of simply having batteries available. It’s hard to imagine a scenario where rechargeables are not being used, but it happens. And if rechargeables are being used, it’s important that the discharged batteries are distinguished somehow from the freshly charged cells, so we don’t inadvertently put dying batteries into our transmitters or receivers. Simply establishing a formal, standardized process so this happens the same way every time makes sound sense.
Final Thoughts
A general rule that applies across all of pro audio is get it right at the source. In this case, I refer specifically to the quality of our signal before it ever gets to a transmitter (and what happens to it after it’s captured by the receiver). If we hear distortion, particularly in the case of a newly integrated wireless system, the blame is frequently ascribed to the wireless part of the process. Strictly speaking, this is probably good troubleshooting — usually if things go sideways with the intro of a new system, the problem lies within the new system. But with wireless, the issue is more likely where the old system bumps into the new system. I’m alluding to gain staging: Ensure that the signal from our mic or instrument beltpack is at the proper level for the transmitter’s input. If it’s too hot, we are transmitting a distorted signal. On the other end of the transmission, confirm that the output of the receiver isn’t too hot for our console input. Bottom line — the more gain stages, the more we must pay attention.
There are many ways we can maximize the quality of our wireless systems. A one-time once-over of the totality of the system is a good idea, as are periodic revisits to ensure it’s still doing what we want.
John McJunkin is an adjunct professor at Grand Canyon University.
