Loudspeaker audio at an event

[Conan Stott]

Audio question: If you are filming someone speaking from microphone at an event, where the sound of their voice is being projected over speakers, do you put your own mic up next to the person to record them directly? What does that sound like? Or do you just have a good mic from the audience and get the “room sound” which I imagine is like loud speaker quality of audio slightly muffled?

First time doing an announcement gig

[Mark Suszko]

OK, I have done this pretty much weekly for three decades, for news events and conventions, training seminars, etc… And can tell you there are a LOT of ways to get this done. You don’t mic the speaker cabinet except as a last resort or backup, because that’s generally the worst audio, after relying on a distant shotgun. Don’t be that guy, because people will forgive sloppy video as long as the audio is clean, but never the reverse. The first thing to go for is to get an independent mic on the lectern, just to grab the speaker’s voice for your feed, and/or, you tap into the same mic being used to feed that PA.

How do you do that? If the PA mic is hard-wired, you could use a y-connector cable at the mic, and split off your own cable to your camera. The PA operator may not allow that, because it weakens his incoming signal, and also, you never do that without first asking their permission. Throw your own mic and table stand up there. If they don’t allow your stand, you could try a tiny hardwired lav mic clipped to their existing stand, or anywhere on the lectern, really, because lavs are omni-directional. In addition to stick and lav mics I also carry a shotgun mic and a PZM boundary mic which is very flat and can be hidden anywhere on a flat surface using gaffer tape. If the camera position is within about 15 feet or less of the speaker, a high-end shotgun *might* work… but only if the speaker stands very still the entire time.

Or better, go to the mixing board for that PA system, and bring an adapter for all the common types of available connection: an XLR, a Quarter-Phone, Mini/headphone, an RCA, even. You can get these adapters cheap at Markertek or Monoprice as well as Amazon. Me, I still own a tacklebox full of them from Radio Shack 🙂 Never count on the board operator to have these – it is your responsibility to be prepared and equipped. For anything!

It helps to also own a line-to-mic transformer, adjustable impedance pad, or attenuator, like the Shure A 15 AS. A very solid toy that I’ve used for years. Lets you drop a too-hot signal down to where it works with your camera’s mic-input. Just Plain Works. Bring your little bag of adapters to the PA system operator or DJ mixer person, greet them with a greeting of Hello, Brother! …and politely ask to tap in, however they can do it. They will either have a “line-level” or “mic-level” output available off the board. Be sure to ask which it is. If the sound you get is blowing out too loud and distorted, chances are you have a line-level signal going into your mic-level impedance camera input. Some cameras have a mic/line selector switch, use this to help fix the issue. In some cameras it isn’t a physical switch but a menu setting. Or get the Shure A-15 and interpose that in the signal chain and drop the level before it gets to your camera. Some audio boards, the operator can trim the output level too, ask for that if it’s too hot. Obviously you want to get to the venue early for doing all this and testing it.

At bigger events, with live board operators, look for/ask for an audio “mult box”, also known as an audio distribution amplifier. This is the audio equivalent of a multiple-outlet AC power strip, but for audio. Many camera operators can tap in to one feed this way, and it’s a preferred way, common at news events. Some DJ’s or PA operators will instead offer a “DI” – that’s a “Direct Box”; again, these can be used to change the signal level to what you need.

What if the mic being used is a wireless hand-held or lav?

Nothing says you can’t bring your -own- wireless lav, on another channel, to add to the one being worn. Unless the venue says no to that. Then you’re back to tapping into the audio board output, or adding a y-splitter to the output of their wireless receiver system. If you own a wireless system compatible with the venue, you might just ask the receiver frequency and tune yours to match it. As an aside, some churches have a wireless sound system used by the hard-of-hearing, with little pocket receivers they loan out; you add your own earbuds… well, these can also feed a camera, if you have the right adapters, and it should be a pretty clean feed. Did that for weddings for years.

Now, a trend I’ve come across mostly at hotels and banquet halls is, they are too cheap to use audio staff, or have had too many unskilled users mess audio things up over the years, and so have “simplified” their audio system for a room to the point where you have *nothing * to tap into – it’s a sealed system in a box or room you can’t access, and the only accessible controls are an on/off and volume control, if that. Or, the event is using a very small-scale self-contained PA system, again, with no output jack on it that you can tap. Then you might have to mic a speaker grille or cabinet – if you can reach those. But there is one other thing you can try first that’s still better. Have a small audio recorder, or use your iPhone set on the free audio recording function, set that on the lectern with some gaff tape to keep it from sliding, and just let it roll continually the entire event. Bring that back to the edit bay: both FCPX and Premiere Pro (and probably Resolve) can automatically synch up this closer audio with whatever wild sound you got from the actual camera position. I find iPhones are pretty phenomenal for this, even ones that are not active as a phone any more still make great audio recorders and cameras – cheap at pawn shops. I own an older audio recorder, a Tascam DR05, works terrific for this as well, and cheap off ebay.

Congratulations for reading this far. You’re here because you tried every previous trick I listed above, and you’re still… stuck, Okay, reluctantly, this is how to mic the speaker cabs, damnit.

Check the back of the speaker: some have an “out” or “through” connector, meant for chaining to more speakers. It might be possible to tap into that with an adapter. If the speakers are connected with a pair of twisted wires and spring connectors, and you have an adapter with matching bare wires, or alligator clips, you could try to add yours to theirs, but you’ll need a line -to-mic transformer or a “pad” to bring the level down to camera mic level. But that will be way cleaner than picking up the cabinet acoustically, with all the other room noise. I hope you see how important it is to have a huge collection of various audio adaptors if you take your work seriously. You need not buy them all at once, but keep adding to the kit as you go. It pays off.

Last chance; mic the front of the speaker cabinet (sighs) Okay…

The type of mic is important; you need a dynamic mic, that is, one that doesn’t need external power to work. Classic dynamic “stick” mics include the Shure Sm57 or SM58, the ElectroVoice EV 635 series, or something like those, that will not be over-saturated by the loudness of the speaker. These have a cardioid or super-cardioid pickup pattern that is pretty directional, rejecting the crowd and venue noise around it. Get the mic up close to the grille of the speaker, without touching it. I tend not to point it right at the grille but rather at 45 to 90 degrees to it, pointed towards floor or ceiling, you’re playing *across* it, not directly into it. Why? Plosives: the B and P sounds that will pop too hard. And I listen to hear if there is any buzzing getting picked up, then back off a little. If you look at how some bands mic their guitar amps, they sometimes hang the mic down by its cord with some gaffer tape to dangle in front of the speaker cone at 90 degrees relative to the cone.

If the room you’re in has ceiling-mounted, down-facing speakers only, (conference rooms and banquet halls with sealed, “hands-off” PA systems often do this) I was able to handle that with a shotgun mic, gaff-taped to a telescoping 8-foot light stand, and then elevated straight up at the ceiling speaker, in a back corner of the banquet hall, so the final mic-to-speaker distance was only 2-3 feet… The shotgun rejects all noise from the sides, and only grabs what is directly ahead of it. Good shotguns cost a lot. Worth it. The mid to lower level cost shotguns like the Rode are popular. But if you’re working on a lower resource scale than that, I had good luck with a Takstar mini shotgun off Amazon.

There you go. That is every trick in my audio capture book. Pass it on. And let me know how you did!