Tricks of the Trade, April 2000USING LAVALIER MICROPHONES 5/17/2004 8:00 AM Eastern
I was born in England, and my mum was always asking me if I needed to use the "lav," so when I was asked to write some thoughts about "using lavs," I couldn't help but laugh. But using lav microphones can be a scary business. The idea of strapping a transmitter onto a performer and listening to the person sing through a tiny electret microphone pinned to their chest area can be exciting and terrifying.
A LITTLE LAV HISTORY
Sony's ECM-50 provided my first experiences using lavalier microphones. The ECM-50 was placed on the chest, tie, lapel, bra and sometimes collar of the actor's coat. This mic position never suffered from sweat or hat reflection problems, it only suffered from sounding...bad. But truthfully, given the rudimentary sound systems in use at that time, nearly everything sounded bad. And about the only time we ever heard high frequencies come through the performer's input channel was when the mic connector or cable broke on a mic buried under a performer's chest-clinging garments.
Later, I was the mixing engineer working on Evita in London, where we had really stepped up to the plate, using six (!) body microphones with six transmitters. This was pushing the limits of technology. Sound designer Abe Jacob used the sixth transmitter for only one scene, where Evita dresses herself onstage and, therefore, covered her existing ECM-50. We had the sixth unit preset inside the newly worn jacket. Pretty cool, eh? one evening, Kate Bush's management approached me after a performance, asking how we were able to amplify the voices without using cable microphones and whether it would work for Kate.
After spending years of experimenting with Sony ECM-50s, 150s, 77s, Tram microphones and anything else that might possibly capture a sound resembling a human voice, Sennheiser debuted its MKE-2. Now we had a much smaller microphone with thinner cable and a connector that no one this side of nerd-dom could fix. But it had (and still has) a frequency response that gave a boost in the high end, which provided the audience the pleasure of hearing precisely how well-starched the costumes were.
Starlight Express, the musical, well...the show on roller skates, presented a chance to place lavalier microphones in front of the performer's face, as most of the costume designs had headgear and could share the real estate with the sound department. Sound designer Martin Levan seized the opportunity, and the show sounded great. With the microphones placed directly in front of the performers' mouths, it wasn't so far removed from conventional studio techniques but with movement.
Along with the popular Sennheiser MKE-2 came the commonly referred-to "head microphone" or "ear microphone." This began the trend of sound designers placing microphones in performers' hairlines. As opposed to the chest position, the hair position offered dramatically improved reproduction, to the point where the industry needed better loudspeakers that were actually designed for the requirements of live theater.
one should note that an actor whose head is motionless and has a large resonant chest has a good chance of sounding better with the microphone attached to the chest. Trial and error should be considered, but as soon as the head starts moving-thus changing the mouth-to-mic distance with every motivated gesture-the mixing engineer has to treat the input fader like a yo-yo.
THIS YEAR'S MODELS
Today, we work with mics that are about the size of a matchstick head, placed on an actor's head. But now, instead of having the problem of a mic covered with garments, we have mics that are typically covered with sweat and/or hats. It's little wonder that critics say, "It doesn't sound very natural."
Fortunately, with a number of new mic models coming to market during the past couple years, users have a wider choice of small mics, including the DPA 4060 series, Sennheiser MKE-2 series, Sanken, Countryman, AKG, Beyer, Sony and Shure. The most popular in the U.S. and UK theater markets are DPA, Sennheiser and Countryman. DPA first came to the rescue with a usable small, omnidirectional, sweat-tolerant capsule a few years ago, after the Sennheiser MKE-2 had been the dominant choice for more than 15 years, with its sweat-intolerant capsule. Last year, Sennheiser's Gold MKE-2 became available with advertised sweat tolerance. Countryman's B3 mic is popular, but more interesting is the new B6, which is the tiniest microphone I have ever seen.
PLACING THE LAVS
The first day the actors arrive at the theater for rehearsal, the microphones should be placed on them. Some actors have done it before and know the routine-others have done it before and are still clueless. Some actors get headaches from the 3mm elastic headbands (these bands are pre-made before the actors arrive), some have expensive hair implants and some wear a street toupee, while others are bald. Each performer is unique, of course, and needs some personal attention.
A visit to the rehearsal hall can save a lot of time. Watch the performers and make a list of possible requirements. Try to get approval of the director to be in the rehearsal hall for the last seven to ten days and set up the wireless system in the rehearsal hall with a small console feeding a single near-field loudspeaker. This arrangement lets the mixing engineer get ahead of the learning game and allows you to anticipate and troubleshoot 80% of your problems on the front end.
Currently, the most popular ear rigging uses a Telex ear clip. A mic is attached to this clip, usually over the ear. When the microphone can be, or needs to be, extended, floral wire can be run alongside the microphone cable to enable a more rigid-but flexible-way to position the microphone down the side of the actor's face. Unfortunately, this positioning can mean that sweat will creep or gush down the side of the performer's face and along the cable until it reaches the microphone's head, and here it will have a saltwater orgy on top of and inside the microphone capsule. This trouble can be reduced by the manner of which the floral wire is attached to the microphone cable; use heat shrink, or preferably, rubber sleeves and your Hellerman tool. (The Hellerman tool is a three-pronged device that enables you to stretch the width of a 1-inch rubber sleeve enabling the floral and microphone cable to be placed within the sleeve. There seems to be some mystery about purchasing the Hellerman tool in the U.S., so if you can't find one locally, try calling one of the Broadway theater audio rental companies in the New York area.)
If the floral wire is attached properly, sweat will usually reach the uneven rubber-sleeved trail and fall off the cable before it arrives at the microphone head. If not, then the o-ring comes into play. Place a small plumber's o-ring over the cable firmly but close to the tip of the mic head without impeding the microphone's specification. The fact that the microphone is already impeded by the pulsating cheek of the actor is "neither here nor there." once the clip is in place, the cable can be stunningly and tastefully draped around the back of our performer's head, where it is taped, medically, to the back of the neck and then wound down to the invisibly placed transmitter. A thin piece of tape usually is placed behind the ear to hold the clip and microphone cable as close to the skin as possible, thereby losing the android effect that can come with behind-the-ear placement.
If you wish to place a mic in the center of the head, just down from hairline, it is best to use an elastic headband. The microphone cable is simply wrapped around the elastic and then threaded through a loop that is made in the elastic by making a finger twist in the center of the forehead. This is the quickest and most secure way to place a mic on an actor for rehearsals and, in some cases, for actual performances.
Toupee clips are another form of attachment. The toupee clip has a small hole on each side where you can thread a stretched piece of 3mm elastic across the clip. This makes a loop so the mic cable can be threaded through to make an attachment to the clip. Two clips are then placed so that they can be secured to the performer's hair toward the front and halfway down the back of the head.
Placing microphones in wigs is a really good technique, because the wig cap can hold the mic cable in place, then the wig is placed on the performer. A buttonhole should be placed in the wig (by the wig/hair designer) in the center and about 2 inches away from the front hairline. The microphone head is threaded through the wig's buttonhole and laid on top of the false hair and placed at the hairline or (hopefully) below. Don't place a microphone under the gauze of a wig, because then the microphone will be squashed against the forehead and will sound weird and be sitting in a river of sweat.
Having sorted out the issues surrounding amplifying a voice through a tiny little, sweat-tolerant mic that's hidden in the hairline, now let's add a hat. When a hat is worn in a scene, it can make the performer sound like he or she is vocalizing through a toilet roll. Most hat brims have a tendency to reflect the performer's voice, much like cupping your hands around your own mouth. Your goal is to do anything you can to stop the reflection without irritating the costume designer.
What makes this complicated is the fact that practically no one hears your mic placement problems during rehearsals. It's not until the show is costumed, lit and in previews that any concern is given to the beautifully dressed, stunning-looking actor who sounds like Daffy Duck in the Lincoln Tunnel. Solving this problem is, of course, less a matter of technique and more one of diplomacy.
When checking lavalier microphones before a performance, I strongly suggest that the person who mixes the performance is the person who checks out the mics and system. This should be done at the front-of-house console, and I suggest each microphone is listened to on headphones for creaks, cracks, gain and dullness. Then turn up the P.A. to confirm that routing is correct to the speakers. The person who mixes should be responsible for the final checkout before the performance. If something goes wrong during the performance, it is crucial for the mixing engineer to have known how every microphone sounded, until the time when the curtain rises.
THE LAVS TOOL BAG
Rubber sleeves with a Hellerman tool
Telex ear clips
Clear silicon compound
Artist's colored acrylic pens
3mm rounded elastic
Toupee clips (small and medium sized)
3M Tegaderm medical tape
3M Microspore medical tape
Any other kind of tape that might stick to a performer without the aid of a staple gun.