Here are some of the most commonly asked questions by churches regarding microphones.

Q. What is included in a "wireless" microphone system?
A: A wireless microphone system includes a minimum of two or three components.

The transmitter
Available in a self-contained handheld mic or as a belt pack with a lavalier or headworn mic, this device is a small radio (RF) transmitter. Transmitters can be fixed or variable in frequency.

The receiver
The receiver takes the signal from the transmitter and outputs audio to your sound system. Receivers can also be fixed or variable in frequency. It is important to note that most wireless systems can be identified by the model number and frequency band that are on the back of the receiver.

The microphone
Wireless handheld transmitters are self-contained. Belt pack transmitters use an external, very small microphone element, which is inconspicuous. Microphones are available from a variety of manufacturers to replace and upgrade your existing systems. Headworn and lightweight "earset" microphones are also available for the ultimate in sonic fidelity and comfort. You will need to know the manufacturer and model of your wireless system to specify replacements.

A wireless microphone system may also contain the following components.

An antenna distribution system
When multiple wireless systems are used, it is common to have an antenna distribution system that feeds all of the receivers from one set of antennas. It is typical for these systems also to feature AC or DC power distribution to multiple wireless receivers. An antenna distribution system is an excellent upgrade when you already have three or more wireless systems. Most distributors can provide antenna distribution systems for almost any brand of wireless. You will need to know the make and model of your existing wireless systems, as well as the frequency band.

Accessory antenna/s
Accessory antennas are commonly added for long range or very directional applications or for coordinating dozens of wireless microphones. An antenna booster is typically

inserted near the antenna. Accessory antennas and boosters can provide a dramatic improvement to your wireless systems.

Q: How many microphones can I add to my existing wireless system?
A: Running multiple wireless systems requires careful frequency coordination to avoid interference. Please contact your distributor for assistance with this process.

Q: I don't know whether to get a wireless microphone system or a wired one. How do I choose?
A: Unless you need the mobility of a wireless mic, stay with wired. The initial cost is much lower, they require less maintenance, and you don't have to keep buying batteries.
 
Q: I'd like to use rechargeable batteries in my wireless mics. What kind do you recommend?
A: We have not had success with rechargeable "9 volt" batteries. They just don't have the capacity needed to run a transmitter for more than about an hour. For systems using AAs, the NiMH batteries used for digital cameras can work well. If you use rechargeable batteries, avoid surprises in the middle of a show by keeping battery sets matched and by tracking usage. This is important because a simple voltage check won't tell you how much capacity is left, as it will with conventional batteries.

Q: We are using a portable sound system and getting feedback. What should we do?
A: It is important to keep the microphone out of the coverage pattern of the speakers. You want to set up the system so the speaker energy goes out to the audience, not back into the microphone.
 
A basic rule of sound systems is to get the speakers up, preferably at least three feet above audience head height. This ensures the sound will get to the audience members at the rear and doesn't blast out the people in front.
 
Set up the system so that the speakers are in front of the microphone. The mic should not be pointing at the speakers. Don't walk right in front of the speakers with an open mic.
 
Also, avoid using too much gain. If you find that you're holding the mic more than a foot from your mouth, reduce the system gain and work six inches or less from the microphone.

Andy Krahn is the audio project manager for PNTA, www.pnta.com, an A/V equipment supplier that assists churches with integrating and retrofitting system components to keep lighting control, sound, and special effects equipment up and running.