A wireless mic runs with no physical cable that directly connects it to the related amplifier.

A wireless mic system enables the user’s voice to be transmitted to its receiver which is set in the sound system in a wireless way. The sound system then enhances the signal from the receiver and delivers it through the system’s speaker.

A wireless system is a system of three main components, namely input device, transmitter, and receiver. They run together to achieve a smooth operation of the whole system.

1. Input device
The input device, which is always a microphone, offers the audio signal that will be sent out by the transmitter. It is hand-held or hands-free and connects to the transmitter.

2. Transmitter
The transmitter is responsible for the conversion of the audio from the microphone to radio waves and then the transmission of such waves to the receiver through an antenna. The antenna probably is out at the bottom of the wireless microphone transmitter or is hidden inside.

3. Receiver
The receiver is intended to collect the radio signal sent over by the transmitter and change it back into an audio signal so that it can be amplified by the sound system. The receiver can be connected to a typical microphone input of a sound system. Its output is electrically equal to a standard microphone signal.
Note:

Different brands of wireless mic system are incompatible with each other. This is because each manufacturer may use specific radio frequencies and adopt different methods of transmission.
A transmitter in general only runs with the specific receiver it was designed and launched to be with. In fact, even the same manufacturer of both pieces may use different models and frequencies for different kits.

How does the system work?

A professional wireless microphone system, unlike a traditional wired microphone that changes sound waves into an electrical audio signal which then goes to the sound system using a cable, converts the audio signal sent by the microphone to a radio signal which then is delivered to the sound system by a transmitter. When the transmitter picks up the radio signal, the receiver, which is always located near the sound system, is tuned to the same frequency to convert the radio signal back into an audio signal and feed it to the sound system by a cable.

Every performer using a wireless microphone at a particular location, probably a theater, church, or school, must use a system operating on a different frequency. “Frequency sharing” is impossible for wireless systems at one location because there would be interference with each other. This is similar to the situation where two television stations in the same city try to broadcast on the same channel. If two performers at one site continue trying to use the same frequency at the same time, neither voice will be picked up clearly. This is a limitation on the number of wireless mic systems that can be used simultaneously at one location. Appropriate frequencies should be selected for specific needs - reputable manufacturers and dealers of wireless systems would do you a favor.

Who benefits from such systems?

The answer is quite simple: anyone who wants to set themselves free from the restrictions exerted by cables and cords on their performance.

Musicians are allowed to use single or multi-channel good wireless mic systems to accommodate their entire bands.
Presenters could better engage the audience if they’re not clung to the podium.
Tour guides may walk into among the tourists freely to share excitement together.  
Personal trainers or fitness instructors would move in an unencumbered and hands-free way.
Journalists and content creators might enjoy absolute freedom on each location.

A completely new world full of performance possibilities would be open to you once you remove the cable. The handsfree wireless microphone systems, with increasingly improved sound quality and reliability as well as decreasing cost, is now well received by the market. They are booming because they remove the microphone cable and allow you users to walk across the stage, into among the audience, and even outdoors. Under this, performers or presenters would enjoy better mobility, flexibility, and ability to talk with their hands and perform with their hands!

Still have some questions? See Why and how to choose wireless microphone systems and seriously consider it.