Wireless Microphone Buyers Guide

A wireless system’s main purpose is to replace the cable that connects a microphone or instrument to an audio system. Yet this technology has dramatically changed almost every aspect of live sound. “Why go wireless?” is a question from days gone by. Now the question is “Why not?” Once upon a time, wireless microphones were unique to the point of being a novelty. Their installation and operation required a bit of technical know-how—and patience. Beginning in the early 1980s, Samson was one of the first wireless manufacturers offering affordable solutions that helped shape modern musical and theatrical performances. Today, Samson offers wireless microphone systems for many applications including musical performance, theatrical production, fitness instruction, video production, presentations, and houses of worship.

Wireless Basics

All wireless microphone systems require three elements: Microphone, Transmitter and Receiver

The Microphone

The microphone captures sound waves and converts them into electrical signals which are fed to the transmitter. Coming in a variety of formats and designs, selecting the right microphone will ensure the best results in any given situation, from handheld, lavalier, headset, earset to clip-on instrument microphones. In the case of Guitar and Bass Wireless Systems, a 1/4″ plug that is connected into an instrument’s output jack is used in place of a microphone capsule.

The Transmitter

The transmitter has two main functions. The first is to provide power to the microphone—if needed. The second is to take the signal from the microphone, convert it into radio waves, and send it to the receiver. Transmitters are designed to be compact and unobtrusive. The transmitter is often in the form of a beltpack, or it can be incorporated into the body of the microphone, or connected by way of a module.

The Receiver

The receiver is the last stop for the audio signal in a wireless system. Once the signal is received from the transmitter, it is converted back to an audio signal that can be connected to the house mixing console, a personal combo amplifier, your PA system, as well as a personal computer or digital camera. Be sure that the receiver for the wireless system you choose has the right outputs to connect to your other equipment—or make sure you have the necessary adaptors needed to make the proper connections.

Analog vs Digital

Wireless audio systems use radio waves to carry a signal. Virtually all analog wireless audio uses a system called frequency modulation (FM)—when referring to a digital wireless system, the technique is called frequency shift keying (FSK). The term itself is descriptive of the process: The frequency of an electromagnetic radio wave is modulated (that is, continuously varied) by an electrical audio wave, or digital in the case of a digital system a digital bit (represented by a 0 or 1). The radio wave itself is inaudible, since it is well above the range of human hearing (which only extends as high as about 20 kHz). Its sole function is to carry the signal over long distances—thus, it is called a carrier signal. It is only when a radio wave is carrying information that it can be referred to as a radio signal.

The question of which type of system is better or worse is not so straightforward. Each type of wireless method has it advantages and disadvantages. There are factors not related to the transmission method that can make a system sound better or be preferable for your application, such as the microphone, or size/design of the receiver.

Digital wireless microphone systems tend to have better dynamic range and frequency response as well as not incurring noise at the end of the wireless range. Analog systems have to compress the dynamic range prior to transmission. That isn’t to say analog systems are noisy, modern analog wireless systems have been designed to include high-quality audio sections that are heard on the biggest stages and broadcasts around the world. However, analog systems will broadcast better at the end of the wireless range, although with audible noise, whereas with a digital system may drop out completely.

Latency is the time delay between the signal input and output in a system. Analog systems have virtually no latency, while digital wireless systems experience some amount of latency. The amount of latency that can be tolerated depends on the application as well as the people involved. For speaking or video applications, latencies under 20ms are acceptable. However, for performance applications, especially those where a performer will be able to monitor themselves or need to lock in with a band, latency generally needs to be much lower to be acceptable.

Both analog and digital systems’ performance can be diminished by RF (radio frequency) interference. When using a UHF or VHF system, you need to coordinate the frequencies to avoid direct interference from active TV broadcast and other wireless sources, as well as other performers using a wireless system. Many digital wireless systems do not give the user the ability to select the operating channel, instead they automatically scan and hop between frequencies to avoid interference from other devices in the spectrum. And with the number of wireless devices (including WIFI) taking up bandwidth in the frequencies ranges that digital wireless microphones operate, limit the number of systems that can operate simultaneously.

Some Closing Thoughts

Wireless microphones are great. They can eliminate long and unsightly cable runs. They provide heightened levels of mobility to dynamic performers of all stripes. They offer great convenience to news gathers and online content creators by offering cable-free connections, plus discreet and unobtrusive mic placement. Samson brings continuous innovation to the wireless microphone industry, creating systems that are designed to ensure your audio requirements are achieved for whatever your application.