This is going to be great. For starters, this is a reader submitted topic. I love those. For another thing, it's about something that goes horribly wrong during a service. And for us tech guys, it's kind of like a train wreck. You know you shouldn't look, but you just can't help it. Then you say, "Phew! At least I wasn't mixing when that happened!" So here we are. In the middle of service, and the pastor steps up to pray. His mic is on, everything is working perfectly. And then...well, take a listen.
Bad, Bad Sounds During Prayer
I don't know about you, but that makes the hair stand up on the back of my neck. Call me a perfectionist, call me paranoid, but I can't stand it when stuff like that happens during a service. It's just horrifying to me. Now, this pastor handled it well, but the mood was still broken. I always tell our tech volunteers that our job is to create an atmosphere of worship. People should be able to come and meet with God without having to block out explosive noises from the sound system.
OK, enough ranting. The question was posed to me, "What could the FOH engineer have done to either prevent this, or minimize the damage?" Personally, I'm a big fan of "prevent this."But before we can prevent anything, we need to know what we're dealing with. The initial diagnosis of the offending noise was a bad cable to the bass guitar. (I think we have an update, but I'll save that for the end because it doesn't help make my point--see how I am?)
Test and Fix Them Cables
So let's consider the "bad cable" theory. How do we prevent a bad cable? For starters, test them. We just did this a few months ago. We pulled all the cables off the rack and tested them. Every single one. It took about an hour and a half. We plugged each into a cable tester and gave them a shake all up and down the length of each cable. Ones that failed were put aside, and were fixed them later. Ones that couldn't be fixed quickly were thrown away. The way I see it, there's pretty much no excuse to use bad cables more than once. And if you test them regularly, you can head most of this off at the pass. If all your cables are good, you won't have issues like this. Except when good cables go bad...
My Bible says that on the 5th day, God created the fish, the sea and mute groups. And VCAs/DCAs. And He commanded that we use them. Often. That's the rarely quoted 11th commandment, "Thou shalt mute all unused inputs until just a moment before they whilst be used, and promptly re-mute them again after they are done being used" (and we pronounce that "use-ed"). As you may have guessed, I'm a big fan of muting inputs, or turning them off when not in use with a VCA or DCA. I'm so big on this that I will often not un-mute a mic until the person is inhaling just before they are about to speak or sing. And as soon as they're done, the input is off. This is important for several reasons.
During prayer, or speaking, there is nothing else going on in the system to cover up bad sounds. What kind of bad sounds? Well, how about the one we just heard. Or how about during a wedding and someone is prepping for a service backstage and starts plugging mics into channels that should be off (but aren't). Or how about the guitar player that comes up during prayer and decides to tune, only instead of tuning clicks the tuner off instead of on. Those kind of sounds. If someone were to be following my "all inputs off except the active one" rule, and a cable went bad during prayer, no one would have been the wiser.
Almost every board I've worked on has some type of signal indication light on each channel. If the band comes up during a prayer (their channels are all off, of course), and you glance down and see a channel meter or signal present light flashing when it wasn't before, put on the headphones and take a listen through the PFL (or solo) bus (not in the house) and see what it is. If it's a cable gone bad, don't open that channel. It's our jobs as FOH engineers to keep tabs on this stuff.
The Nuclear Option
Sometimes really, really bad stuff happens and you have no control over it. It might be an unexpected power surge that fries a power supply (of course, you should be surge protected…). It could be quick brown or black out (it's not a bad idea to have your FOH desk on a UPS…). Sometimes a piece of equipment fails in a catastrophic way. In any of those cases, I would say you have about 1-2 seconds to figure out if the problem is on an individual channel, or a group, or a mix bus that you can pull down really fast. If you can't find it, you have to go nuclear and pull the mains down. In rare cases, even that won't work, and you might have to take the whole system down. How you do that will vary from church to church, but do you have a plan for it?
Some would suggest that I'm making too big a deal of this. After all, these are relatively rare instances. I would argue that these are extremely rare cases (at least in places I've worked) because I make a big deal of this. The old adage, "An ounce of prevention is worth a pound of cure," certainly applies to the world of live sound, lights and video. If we maintain our systems well, take care of our equipment, pay attention and follow solid live production practices, we can make these hugely obnoxious problems a thing of the past. Go ahead, listen one more time...
After I talked some more with my friend, he informed me that he has a caution light showing on the console, indicating a possible problem with the power supply for the desk. This could account for the noise. Time for a service call...And don't put it off, either!