Hiding Lavalier Mics Doesn’t Have To Be Scary – Part I

That mic is almost as big as his tie!
Ed McMahon selling Alpo on The Tonight Show Starring Johnny Carson

One thing we haven’t seen for 40+ years on tv is a gigantic bolo-style lavalier microphone around anyone’s neck. If you watch reality shows like Big Brother, you might see the same style being used with more modern microphones, just on people with way less clothing. Thanks for wearing a shirt, Ed McMahon.

People without shirts wearing microphones
Big Brother 15, CBS

Think about that positioning and the lavaliere (a pendant hanging centered on a necklace) this type of microphone is named after. While you can clip and attach them nearly anywhere now, centered on your chest is an ideal general-purpose position, especially for sweaty people without shirts.

Over this series, I’m going to talk about microphone polar patterns, lav mic basics, and some simple ways you can approach mounting them on talent. Regardless of what I tell you here, play around with your mics. Test attaching them to yourself and other [consenting adults] people to see what sounds best to you.

Typical Microphone Patterns On Set

Hypercardioid Polar Pattern

If you’ve worked with microphones, you probably know they come in different polar patterns. Cardioid, Hypercardioid, Omnidirectional, and Lobar (or Supercardioid) are the ones you typically see in film and video production. Lobar is for shotgun microphones, so you won’t see it in a lav (though I’m very ready to be wrong), and Hyper-Cardioid is a more focused Cardioid with a smaller lobe of pickup sensitivity 180 degrees from the front of the capsule.

Cardioid Polar Pattern

Handheld microphones are typically Cardioid (rounded heart shape) because they focus more on what is in front and just to the sides of them and reject more of what is directly behind them. In live environments, this is incredibly helpful to avoid feedback. As you could then guess, lav mics with a cardioid polar pattern are typically used in live settings like conferences and broadcast media. One of the higher quality cardioid lavs you’ll see is the DPA 4080. They’re usually chest-mounted, visible, and clipped on if they’re not on a headset. Watch hosts and guests on any live-captured tv show like late-night shows and the news to get an idea of how they’re typically mounted outside of clothing.

Omnidirectional Polar Pattern

In single-camera productions, it’s more typical to use Omnidirectional lavalier mics. They can offer a more natural sound if you’re not fighting noise issues. As the name implies, they usually have a mostly even pickup pattern in a full sphere around the mic capsule. Common models with capsules mounted on the top include the lavs Sennheiser includes with their wireless systems, Countryman B3, & Sanken COS-11D. A slightly different style of Omni lav you’ll see are Tram TR50-style mics like the Lectrosonics M152 they include with their wireless transmitters, Countryman EMW or Sonotrim lavs (if you know a pro mixer). These are less sensitive to physical noise on the flat plastic side opposite of the mic grille and are often mounted with that side facing any physical noise sources like fabric.

Oh Wait, One More “Polar Pattern”

Boundary Microphone “Hemispherical” Polar Pattern

When placed on the chest, Omni-patterned lavs pick up sound in a polar pattern that looks like a hemisphere, much like a boundary microphone you’d see on a conference room table. It’s a half-sphere projecting from the chest. This is why you wouldn’t want to use them in a live setting. It’s feedback hell unless turning your back to the speaker makes it stop. The sound produced from a position near the solar plexus is more natural but can be very chest-resonant and many times benefits from tweaking in post.

You still want your Omni lavs centrally placed for uniform sound when the talent moves and adjusts their body. Placement between the lower end of the breastbone and solar plexus generally gives a more natural sound. This is why you’ll often see a mixer asking female talent to attach a lav on a vampire clip near the bottom “valley” of their bra. For men, attaching a mic to their shirt, taping to their chest or using a “mic bra” is a good way to achieve similar hidden placement. In large film productions, they often dedicate time and money to creating permanent lav mic placements inside of costumes.

Next Time . . .

That should give you a more solid grounding on lavalier mics. Next time I’ll work through some mounting positions and techniques with simple examples you can try at home.

Recording Meetings At An Oddly Shaped Table

My good friend Adam knows quite a bit about a great many things. He is excellent at directing his staff to fix workstations and roll-out machine images. Like most people who grew up in the internet age, he’s fairly comfortable with searching Google, leveraging his supreme meta-knowledge, and finding pretty great answers.

[Very smart, accomplished people search for things you might assume they should already know. It’s ok. That knowledge exists on the internet for a reason. You shouldn’t have to store all of it in your brain along with the filmography of that weird character actor, all the notes in F# major scale, and the name of that kid who fell backward out of their chair in high school geography.]

As a part of his job, he was tasked with recording regular board meetings. The table they met at was in a wide U shape, and he found it impossible to get a clean recording (for transcription and recordkeeping) on his Zoom H4n with the two onboard stereo-pattern microphones. Speakers would be too low to be heard and the recording had too much echo to be easily understood.

I can think of multiple solutions to this problem. They all depend on how much money you want to spend and how much time you want to invest in making it work. The simple solution I offered him added marginal expense and works perfectly.

Boundary Microphones

Let’s talk about Boundary (or PZM) microphones.

Think of microphones as having a position relative to surfaces around them and are subject to reflections from each of those surfaces. This might be 3 feet from the ceiling, 5 feet from the right wall, and so on. The range of distances between each reflective surface means that sounds bouncing from each surface and the sound source will all arrive at the microphone at different times.

This means they start to interact in negative ways as they are minimally delayed in different amounts, then get picked up together at once by the microphone pickup. Some of each sound source gets canceled out. Depending on the type of microphone, the size of your room, and what it’s made of, this could result in much worse sound. If you can find a way to minimize the amount of reflection and pick the right microphone, your sound becomes much more direct and cleaner.

Boundary microphones solve this by putting the microphone as close as possible to a reflective surface. This is ideal in a meeting because you can place microphones on the table surface, which extends the boundary below the microphone to essentially the entire table.

Solution

The solution to Adam’s problem was to add in two boundary microphones, similar to the Audio Technica I included a picture of earlier. They both connected over XLR (professional) connections, allowing him to place one boundary microphone midway down each arm of the U-shaped table and point the H4n’s onboard microphones at the base of the U for the remaining speakers, easily covering all three sections of the table. Ideally for mixing, I would like to only use the same type of microphone for a setup like this. This was for record-keeping though, an ideal situation for good-enough but not perfect.

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