
Image courtesy of Willow Creek Community Church, South Barrington, IL
If you're reading this article, you probably know full well that microphones can make or break your Christmas production. Wireless mics play a unique role in the audio chain. If they fail, they take down the entire chain with them, and the audience focuses on strange sounds—or no sound—instead of the performance itself.
If wireless mics succeed, on the other hand, they can ease the burden on the other gear. And they virtually disappear both physically and sonically, placing the focus solely on the actors and the performance.
Here's what you need to consider to ensure ideal selection, placement and maintenance of wireless mics so you can get the best performance this holiday season.
1-Microphone Selection
There are two important sonic specifications that should not be compromised when selecting your mics: flat and full frequency response and wide dynamic range. The frequency response should be flat from 20 Hz to 20,000 Hz within +/- 3 dB. This will ensure that your mics don't sound “airy” or “bassy” by artificially boosting high or low frequencies, but instead provide a natural and accurate reproduction of the actor's real voice.
In addition to the frequency response being flat, the dynamic range should be as wide as possible so that you can use the same mic for anything from soft-spoken whispers to loud vocals on stage. Dynamic range is defined as the ratio between the loudest sounds that can be captured without distortion to the softest sounds that can be captured above the noise floor. Usually, 95-100 dB of dynamic range is more than sufficient for theater mic'ing.
Next, you need to consider the following question: Can the mic be visible at all or does it need to be completely hidden?
If a visible mic is acceptable, choose an earset or headset mic to get the best audio quality and consistency. Of these two choices, the advantages of earsets over headsets is that they are lower profile and are especially well-suited for mic'ing women with long hair or earrings. Headsets generally provide more stability for a wider range of head shapes and sizes, in particular when you need to quickly fit the mic to different actors. However, when fitted carefully, earsets can also be equally as stable as headsets and remain firmly in place throughout the performance.
With both earsets and headsets, the mic element is positioned at the best possible location: near the actor's mouth.
With both earsets and headsets, the mic element is positioned at the best possible location: near the actor's mouth. This location maximizes both gain-before-feedback and isolation by minimizing the distance between the mic and the sound source. Select a mic that can handle such close proximity without distortion during musical numbers or other loud scenes. Although visibility is acceptable, you should still try to keep the mic as hidden as possible. Use the smallest possible earset or headset you can find, with colors matched to popular theatrical make-up shades. This way, only the first few rows of the audience will even see the mics—and they'll have to look very closely to do so.
If the mic must be completely out of sight, then the only option is hiding a lavalier in the hair, by the ear, or on the costume.
If the mic must be completely out of sight, then the only option is hiding a lavalier in the hair, by the ear, or on the costume. When possible, choose a lavalier small enough so that you don't need to hide it completely under clothing—this way you will minimize clothing rustle and muffling of the sound. With a tiny lavalier, your options for placing the mic are virtually endless. Also, since a lavalier is essentially a mic element on a cable, don't underestimate the importance of the cable quality. To achieve solid flex and tensile strength, the inner conductors should be engineered alloys and must be reinforced by Kevlar or Aramid strength members. To endure sweat and moisture without becoming brittle or corroding, the cable jacket should use medical-grade plastics designed to be worn against the skin.
The cable is not the only component that should not fail with sweat: the microphone itself should also be exceptionally sweat-resistant. While the mic rests against the actor's skin, he or she will be wearing elaborate costumes and moving around the stage under hot lights, which means there will be sweating on the mic. If this sweat reaches the mic diaphragm or internal electronics, the sound quality will significantly suffer or, even worse, the mic will “sweat out” and become unusable in the middle of a performance. Mics with plastic protective caps explicitly seal the electronics from any external moisture, and will not “sweat out.”
The cable is not the only component that should not fail with sweat: the microphone itself should also be exceptionally sweat-resistant.
Ruggedness also depends strongly on the manufacturer: select a mic from a reputable company practicing thoughtful and thorough design principles and strict unit testing. Some companies design wireless earsets or headsets to be disposable items rather than products that can be used for hundreds of shows over the course of many years. Before purchasing any mic, ask the company about how they test each mic, and how they determine their specs. Ask how long the mic typically lasts in theatrical environments. There are good reasons why only a handful of manufacturers' mics are used in the biggest theatrical productions.
2-Microphone Placement
The key to placing wireless mics is minimizing the distance from the mic to the source, and keeping this distance constant throughout the performance. For example, a headset mic with the element right by the mouth will provide more isolation and consistency than a lavalier mic clipped to the lapel. When you do use lavaliers, try to position them on the head by either clipping them to the hair or wig, or placing them on the face in front of the ear. Some theaters use heat shrink or tape to adhere a lavalier to floral wire, which they then squeeze onto an actor's ear—the result is essentially a very low-profile, short-boom earset microphone. Others simply tape the lavalier to the face just in front of the ear using hypoallergenic clear tape, taking care not to tape over the head of the mic, which would severely degrade sound quality. Since the microphone is usually fitted before applying make-up, make sure the make-up artists know not to clog the front port of the microphone.
Since the microphone is usually fitted before applying make-up, make sure the make-up artists know not to clog the front port of the microphone.
If you selected a mic with a protective cap, you can always remove the cap and clean out the make-up with soap and water after the show—but remember to put it back on the mic before using it next time. Using tiny lavaliers also opens the possibility of more creative placements, such as running the mic along the frame of a pair of eyeglasses. Use O-rings or small pieces of tape to adhere the mic to the frame. When the actor's costume includes a hat, you can sew the tiny mic into the fabric of the hat and position it in the brim just above the brow. Run the cable down the back to the transmitter or, if you have room, sew a pocket into the hat itself to house the transmitter.
Using tiny lavaliers also opens the possibility of more creative placements, such as running the mic along the frame of a pair of eyeglasses.
With earsets, make sure that the cable does not pull down as the actor turns his head causing the mic to move around during the performance. Tape the cable to the back of the neck, or use a cable clip on the back of the collar. Also, take the time to achieve a good, comfortable fit—rushing the fitting of the mic could mean serious heartache during the performance. For earsets and headsets, you will get the best results with the capsule positioned 1/4 inch behind the corner of the actor's mouth when he smiles. If you still get breath pops at this location, try to move the mic slightly lower than the mouth as well. High-quality earsets use stainless steel tubing for the mic boom, which can be shaped and re-shaped many times by gently bending the tubing over a smooth surface like your thumb. First let the actor try on the earset, then shape it as needed to get the right fit. Once you've achieved this fit, clearly label the mic so you don't need to go through the same process at the next rehearsal or before the actual performance.
For earsets and headsets, you will get the best results with the capsule positioned 1/4 inch behind the corner of the actor's mouth when he smiles.
3-Microphone Maintenance Tips
Maintaining several microphones for a theatrical performance is trickier than simply caring for the one personal microphone used only by the lead pastor. Nevertheless, some theaters can use the same mics for years without any issues. The key to extending the lifetime of your theatrical mics is proper handling and care. The moment a performance is finished, it is tempting to wrap the mic and cable around the transmitter bodypack and throw all of the mics and transmitters into one box for next time—it's late at night, all the actors are tired, and everyone wants to go home. But at that critical moment, you can easily triple the lifetime of your cables and connectors by simply taking a few minutes to disconnect the mic from the wireless transmitter, wrap the cable loosely around your fingers and secure it with a cable-tie, and pack each mic individually in its own carrying case.
... you can easily triple the lifetime of your cables and connectors by simply taking a few minutes to disconnect the mic from the wireless transmitter, wrap the cable loosely around your fingers and secure it with a cable-tie, and pack each mic individually in its own carrying case.
It is also tempting to try and remove the make-up and adhesive residue on the cable by soaking the cable in industrial solvents such as acetone or even turpentine (the main ingredient in “Goo Gone”). This can make the cable jacket brittle or shred apart as the plastics react with the chemicals. Instead, use soap and water or isopropyl alcohol, and wipe the make-up and adhesive off the surface of the jacket. While this may take a few minutes per microphone, again, it will make your equipment last much longer. If you do have problems, contact the manufacturer who should have a customer service-oriented support network in place for taking care of your needs.