Wireless Microphones for Wireless Audio
Wireless microphone systems are sets of components that allow performers, musicians, speakers, content creators, interviewers/interviewees, and actors/actresses to move freely around indoor and outdoor spaces without the hassle of long cables for audio signals. For news gathering, sports broadcasts, concerts, theater, music, and sermons in houses of worship, conferences, weddings, TV/video/film production, and more, wireless audio systems are a vital part of capturing voices, instruments, sound effects, and ambience. Whether you buy a complete wireless system that's ready to use out of the box, or you purchase pieces to upgrade or expand an existing system, it's important to be familiar with the components you're likely to encounter.
Wireless Microphone Systems
Every wireless system requires a device to transmit wireless signal (a transmitter) and a device to receive wireless signal (a receiver). Wireless transmitters will typically be placed where the subjects or sound sources are, while wireless receivers will usually be near the recording device, such as a camera or mixing console. So, the basic signal flow is sound source to transmitter, transmitter to receiver, then receiver to recorder. Complete wireless systems will often include one or more transmitters, a receiver, a microphone (or two), and accessories such as cables and mounting hardware.
Expect to find wireless transmitters in multiple form factors; the three most common are handheld, bodypack/beltpack, and plug-on.
- Bodypack/beltpack transmitters are traditionally designed to be compact, lightweight, easy to hide, and easy to attach to the subjects via supplied belt clips. Bodypack/beltpack transmitters aren't microphones; they normally feature mic input jacks (the connector types are numerous) to allow the connection of a microphone, line-level signal, or musical instrument with the proper cable.
- A handheld transmitter combines a wireless transmitter with a microphone capsule to create a cordless microphone.
- Plug-on transmitters are designed to connect directly to an XLR microphone or a 1/4"-equipped instrument. Consider a plug-on transmitter ideal for a news gathering setup or a wireless guitar system.
Available in a variety of form factors, wireless receivers receive the wireless signal from a transmitter and feed it to outputs for connection to your recording device. Common receiver styles include portable camera-mount, tabletop, rackmount, and plug-in models. Videographers who use DSLR cameras or camcorders generally use camera-mount or plug-in receivers, smartphone-based vloggers and content creators favor portable types, and live event engineers usually go with tabletop or rackmount receivers. Single-channel receivers work with one transmitter at a time, two-channel receivers can simultaneously receive signal from two transmitters, quad-channel receivers allow use of four transmitters per receiver, & so forth.
Microphones for Wireless Systems
In addition to wireless handheld microphones, there are several other types of microphones for wireless systems. In fact, many aren't wireless microphones, but instead utilize cables to connect to wireless transmitters. For example, a lapel mic or lav mic is a miniature microphone that clips onto the subject's clothing. So, a "wireless lavalier microphone" is really just a lapel microphone intended for connection to a wireless transmitter.
Watch a Ted Talks presenter or a guest speaker at a conference, and you'll observe an earset or headset wireless microphone being used to capture that person's voice. Though an earset hooks around one ear and a headset is worn around both ears, these headworn mics share the commonality of having a tiny microphone capsule on a boom, which positions the microphone element near the subjects mouth.