NOTES FROM THE FIELD:We consider ourselves lucky when we get two weeks' notice for a lecture, allowing time to contact volunteers and reserve equipment. The preparation is similar for an interview. The site check, done a week before the event, lets us look for electrical outlets, check the general acoustics of the room, and listen for air conditioner, projector, motor or street noise. Quiet on the set!
On the day of taping, we (the camera operator in training and a coach) arrive an hour before the event starts to stake out a good camera vantage point. We bring twice as many batteries and tapes as we think we'll need. This is where teamwork offers a distinct advantage. One experienced person can do this but it's far more efficient as a team. For tapings using two or more microphones, it's best to bring a third person and a mic mixer.
We plan to place the mic as close to the person speaking as possible. If the speaker habitually walks about the stage, we may need a wireless lapel (lavalier) mic. One of us will personally clip the tiny mic on the speaker inconspicuously above the top button of their shirt or blouse. We hide the wire attached to the transmitter on their belt or in their pocket with the power on. We will have previously loaded the mic transmitter with fresh batteries, then confirmed signal strength through the receiver using headphones.
Another option in a lecture scenario is a mic strapped to the house mic (we can use tape or a velcro strap). We can choose a mic with an omnidirectional, cardiod (slightly directional), or hypercardiod (narrow) pickup pattern, depending on how much we want to restrict the source of the sound. It's a factor of desired isolation or unrestricted inclusion of sound. When it is impractical to get close to the person speaking, we have attached the hypercardiod, a telescopic version of the microphone, to the camera. Other times we have used a PZM (Pressure Zone Microphone) type of mic, mounted on a hard surface (such as a wall, desk, ceiling, floor or 3 foot plexiglas panel on a mount). All but the plexi mounting pick up everything in the room like pens and feet tapping on desks and floors. The PZM on plexi is more directional and useful in aiming toward a dynamic panel of speakers.
The cable will be connected from the camera through the mixer to the mic.
In a sitdown scenario, the interviewer and interviewee can each wear a lapel mic.
In either scenario, XLR cabling to a mixer reduces outside interference (such as radio noise), more so than unshielded cable with 1/4" phone connectors used on musical instruments. We will discuss the use of mixers in another article in the future. MCTV has good how-to's on mixers in their November and December 2003 newsletters.
A shorter version of this article appeared in our February, 2004 newsletter.