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Surfing The Airwaves: Documenting RF Coordination For A Large-Scale Country Music Festival

Three days, from a flying start, many bands, several hundred RF frequencies over what turned out to be not two but four stages, add a roving ENG crew into the mix, and the game is on...
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The wireless system “antenna farm” on the main stage of the Boots n’ Hearts festival in Ontario.

Day 1: It was a Friday in August 2019, just past noon, when I got an e-mail from PRG account manager Erik Paquette: “Hey, are you busy this weekend?”

Well, I wasn’t… and about an hour later, I was in my car, headed north to the iHeart Radio “Boots n’ Hearts” country music festival at Burl’s Creek Event Grounds in Oro-Medonte, Ontario, Canada to serve as the RF (radio frequency) coordinator.

Until 2018, Boots n’ Hearts had always been an off-site coordination. However, that only works if the advance is completely accurate and there’s a relatively light wireless channel count. It hadn’t quite worked out this time, for a number of reasons, so I was enroute to a festival that was already in progress. Just to make things even more interesting, my full kit was on its way back from my last tour, so I was going into this gig with just a handheld TTi spectrum analyzer, a Cub frequency counter, and my laptop, which always travel with me in my backpack.

I got to the site around 4 pm, went straight to the main stage and checked in with monitor engineer Danny Thomas. He had a few issues with the original coordination file (which had been e-mailed to me before I departed). Working from that file, in Intermodulation Analysis System (IAS) software from Professional Wireless Systems, I worked out new frequencies for some of the production microphone and in-ear monitoring systems. That sorted, I checked in with the monitor techs from the two headliners, told them I’d get them sorted ASAP, and then headed down to the second stage with Erik.

The author’s “office” established in a remote region of the
main stage.

On the way down to the stage, Erik was driving the golf cart so I was just playing tourist. Out of the corner of my eye, through a line of trees on the side of the road, I spotted a couple of wireless receivers sitting on a table at the side of a small stage.

I asked Erik: “What goes on at that little stage?” His reply: “What stage?”

That stage hadn’t crossed his radar during any of the advance work, so we made a note to stop on the way back and see what it was all about.

At the second stage, I met with monitor engineer Brandon Tindale, sorted out frequencies for his production mics and “ears” as well as his evening acts. That taken care of, we proceeded back to the mystery stage… which turned out to be a sort of VIP performance area run by the local radio station, which had a small production trailer there as well.

I checked in with the folks there to see if they had any other wireless systems (they said they didn’t), and then made a note of the frequencies of the two systems I saw by the stage. Being about halfway between the main stage and the second stage, it was unlikely that two mid-level wireless systems were going to cause interference issues – but – it was possible that IEM systems at the main stage could step on them, so I decided to add them to my checklist.

Crunching The Numbers

Back at the main stage, I immediately jumped on coordinating the systems for the headliners, Maren Morris and Cole Swindell, both Clair Global acts. After about 20 minutes of number crunching, I had frequencies for both acts, about 20-plus channels of ears and 30 or so of mics and backline. I gave each monitor engineer a list of their frequencies and turned to sorting out Dylan Scott, the act immediately preceding the headliners.

While I was doing that, I also took care of generating alternates for the three frequencies that the headline folks were having issues with. Of these, two were in-ears, one noisy, one weak, while the other was a backline channel with an unknown carrier on it. I didn’t have time to look into that last one, but as it turns out, I would on the last day…

With the evening acts sorted (by this time it was already around 5:30 pm), I dashed over to the catering tent for a quick dinner. Returning to the main stage, I fine-tuned my office (an empty road case as the “table” and a smaller one to sit on) and got ready for the show. Normally, I have at least one analyzer, usually my RF Command Centre, set up to do a wide, continuous sweep of the spectrum that I’m playing in. While slow (because of the wide bandwidth covered) and not super accurate, I find it useful to keep an eye on the big picture and on any trends that are happening.

Because I didn’t have that with me, I employed a different strategy, going through the frequency list for the upcoming act and looking at each frequency, one at a time, within about a 1 MHz span. It allowed me to look at every frequency and see that there’s no conflicting signals on or around it. This obviously needs to be done when the act is getting prepped to go on (so the transmitters are all on).

Having done that as well as checking in with the upcoming monitor engineer to make sure he was happy, it was stand-by time until the next act was getting set.

The first two evening acts came off without a hitch, leaving the final headliner. I went through the same pre-show drill for them, everything worked, and they went on to loud applause. I stayed for the first three songs, checked in with the monitor engineer and got a thumbs up, checked in with Erik and got the “all clear” to beat the traffic to the hotel, about 10 minutes from the venue.

All in all, a good first day.

Day 2: I’ve misplaced my notes for Saturday, but the drill was to be on-site at 8 am to get the two headliners (Miranda Lambert and Kip Moore, for a total of 29 channels of ears and 34 mics and backline) programmed and sound checked, take care of the second stage via phone, text and e-mail, and then start sorting the daytime acts as they came up. Actually, before all of that, I was able to take a site scan and import it into my IAS file for the day, something I hadn’t had time for the day before.

A few things came up that day. As I was scanning around between the Miranda Lambert and Kip Moore sound checks, I stumbled on a frequency that wasn’t in my coordination. I could tell from the waveform on my TTi analyzer that it was an analog transmit but it wasn’t one of the frequencies that I’d assigned to ears, and all of Miranda’s mics and instruments were digital, so they would look different.

Screenshots of the TTi analyzer showing digital (“haystacks”) and one analog (“spikes”) transmissions.

I then thought it might be one of Kip’s instrument systems, possibly left on from the gig the night before (they were just getting guitar stations set up). However, that turned out to not be the case, so I had to look further. Demodulating the signal with the analyzer didn’t tell me anything as there was no audio on it at the time. I then thought that it must be from a nearby ENG crew except that it was 9 o’clock in the morning, we were in an open field, I couldn’t see anything like that (plus there being no one to interview at that hour), and the signal was really strong, like it was right there on the stage.

So, I started looking around and finally found something that I’d never encountered before. Way, way, waaay downstage right (i.e., about as far from my office as you could get), I discovered a single Sennheiser Evolution in-ear system that one of the guitar techs had as part of his rig. I didn’t get the whole explanation of what this was for (something about “being able to hear while I tune”) but I did roll another frequency for it to bring it in line with the coordination.

On The Lookout

Another interaction occurred when I was talking to one of the headline monitor engineers. He happened to glance at my screen (which had IAS up, including that morning’s scan) and said, “Hey, how come you have that DTV channel there and I’ve already done my scan (with Shure Wireless Workbench) and I’m not seeing that?”

Well, here’s why: basically, I was looking for trouble. I had the input on my analyzer set to the highest sensitivity, so it would pick up almost anything that’s on the air in the vicinity. It’s roughly the equivalent of turning the pre-amp gain on a mic input all the way up to see if the stage squeaks when somebody walks on it. So, the extra sensitivity on my analyzer allowed me to pick up a DTV channel that his system missed.

Why does this matter? It’s 9 am, and that act is going to be on stage at least 12 hours later, as late as 10 pm. It’s a well documented fact that radio waves travel farther at night (because they bounce off the ionospshere and are reflected to points that would be over the horizon from the transmit tower). Would that present a problem? Maybe. It’s possible that if his antenna system wasn’t sensitive enough to pick it up in the morning, it still wouldn’t, but it’s more likely that this would show up as an elevated noise floor on any channels tuned within that 6 MHz block.

Modern digital systems like Shure’s Axient Digital (which was in use by this act and many of the other headliners) can still work quite comfortably with an elevated noise floor as long as they have 20 to 30 dB of headroom over the noise, but seeing that RF activity start to light up the bottom few LED’s on the RF display might at the very least cause some consternation. This is an example of how having a dedicated RF coordinator at a festival can make things better, even when the majority of acts are traveling with a very good set of tools for dealing with their wireless needs.

Most of the daytime acts that day were using the supplied production mics and ears, so I had a fairly light day, although I did pick up the occasional unknown transmit. I still couldn’t track down where these were coming from, but they weren’t causing any interference so I just put them on the back burner and kept my eyes open.

The evening acts went quite smoothly with no issues, RF or otherwise (great crew!), which brings us to…

Day 3: Sunday morning presented the same drill, being onsite for headliner set and sound checks at 8 am. The headliners were Kane Brown and Jason Aldean, which worked out to 28 channels of ears and 28 channels of mics and instruments between them.

I’ve always been impressed with the “well-oiled machine” nature of the tech for many country acts and this day was no exception. When we were done with the headliners, both monitor engineers asked me if I wanted them to turn off the transmits on their in-ears. My reply was, “That won’t be necessary as long as you are OK with me turning them off if I need to.” It was indeed OK with them and off they went to their tour buses.

Why leave them on? Besides the fact that the spectrum was relatively open (a luxury, I admit), I had two main reasons.

First, it becomes one more thing to keep track of. As soon as I start rolling frequencies that are dependent on another frequency being turned off, it introduces an “if/then” scenario that I have to remember, as in “if this frequency is turned on, then that frequency won’t work.”

Second, with the aforementioned in mind, I’ve found that as soon as I commit to turning off a band’s ears to make another part of the coordination work, someone is going to come up to me and ask if it’s OK to turn on just this one mix because backline tech “X” has just changed something in their player’s rig and could they just hear it? So, I left those 28 channels of ears on.

Unlike the previous day, four of the daytime acts were traveling with their own RF kits, so I settled down to finding clear, and as much as possible, dedicated spectrum for each act. This took up the next hour or so and the drill was: meet the monitor engineers, get their list of RF requirements, roll some frequencies… then, I would make the same offer to each: if you’re super busy getting your band set up, I’m happy to program your wireless gear for you.

Everyone accepted the offer, which I made because, a) I had the time on my hands, and b) if there was going to be any numeric dyslexia, like “500.025” MHz being entered as “500.250,” there would be no-one but myself to blame. It also gave me a chance to look over their rigs and keep an eye out for any potential problems.

On that front, one trend that I noticed, a direct result of technological change, is the band traveling with just one tech who’s using a rack-mount digital mixer to look after all of the band’s needs, including their monitor mixes, while also mixing the band at front of house via a tablet. This is a great system but one side effect of it is that it means there’s no one “minding the store” on stage.

This came to my attention when one act hit the stage, mid afternoon, and I’d wandered over to their rack to see how the RF was working and immediately saw that one side of the RF receive on the lead vocal channel was not there. I quickly determined that this was due to a bad antenna cable. Now, not having done the load-in, I had no idea which of the 30-odd dead cases in the wings had BNC cable in it, but I did know that main stage monitor engineer Danny Thomas always insists on having some whip antennas in his kit for emergencies. I ran over to monitor world, borrowed a whip and mounted it directly on the rack. Problem solved.

More To The Puzzle

And where are we? Headliners are set, daytime acts are set and in progress, the early evening act is set… it’s just down to monitoring now, right? Well, not quite.

One day, at lunch, I bumped into Angela Smith, an excellent show caller who I’d worked with on many corporate gigs. When I asked what she was doing at Boots n’ Hearts, she told me she was producing the events in “The Barn,” an actual barn a few hundred feet out from stage left. We had one of those, “What goes on over there?” “You know…stuff!” kind of jokey conversations that was interrupted by one of Angela’s staff before I could get to my usual “and do you have any wireless?” question.

“The Barn,” which hosted several events during the festival, also utilized several wireless systems that needed to be accounted for.

Sunday afternoon, while doing one of my routine scans, I happened upon a carrier that wasn’t in my coordination. When I demodulated it, I could hear that it was definitely a wireless mic and it was being used by an emcee as some kind of contest was wrapping up (“…and the winner is…”). Looking around, I saw a guy with a radio and a clipboard near me. I asked if he was with the festival, he replied he was, and I asked him to listen to the signal and tell me where the contest was taking place. He agreed, held my analyzer up to his ear and said, “That’s in the barn.”

So, laptop and analyzer in hand, I went off to the barn, where I met local supplier/tech Bob Gibson. He was using six channels of Sennheiser evolution wireless mics, which he had done his own coordination for.

However, a coordination can’t exist in its own little world, and while he hadn’t really interfered with any of my frequencies, he did tell me that he’d had to move some of his a couple of times, most likely from me allocating main stage in-ears on – or near – his frequencies. I added Bob’s kit as an additional zone in my coordination, thanked him for his cooperation, and assured him that he would have no more surprises through the end of the festival.

And that’s it, right? Almost! Walking back across the backstage compound from dinner, I noticed a couple of artists sitting on the back of a golf cart, talking, but not to each other. Following their gaze, I saw that they were talking towards a video camera on a tripod manned by an ENG crew.

I waited until the interview was done and then introduced myself to the ENG folks. Sure enough, they were using two wireless lav mics for interviews, and when I checked their frequencies to add to my coordination, I found that one of them was an exact duplicate of one of the Kane Brown backline frequencies.

One look at their decidedly “vintage” wireless system was all it took for me to realize that the best course of action was to move the backline frequency (a Shure Axient Digital system that I knew I could find plenty of alternate frequencies for). Accordingly, I notified the Kane Brown crew of the change, verified that it happened, and got ready for the evening shows.

Which all came off perfectly. Three days, from a flying start, many bands, several hundred RF frequencies over what turned out to be not two but four stages, add a roving ENG crew into the mix, and zero wireless issues – and I had fun!

Can’t wait to get out there and do it all again…

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