The Noizeworks Ultimate Guide To Wireless Microphones and Systems. Part One – Wireless Microphone Elements
One of the most buzzword and jargon filled areas of live sound is that of wireless microphone systems (also sometimes known as ‘radio microphones’). So we thought it would be a good idea to create a guide that will help customers through this product area, explaining some of the basic concepts of radio mics, the different types and their application, the UK licensing issues and explaining some of the jargon phrases.
The benefits of cable free wireless microphones and instrument systems are compelling for singers, guitarists and other instrumentalists alike. Not being tethered to a mic cable gives artists and performers the freedom to move, dance and perform with complete freedom of movement. And not just for music applications. Presenters and lecturers can also benefit from wireless microphone technology with cable free operation giving them the ability to demonstrate and articulate more freely. This freedom can be further enhanced with the application of different microphone types such as headset and lapel (tie-clip) type microphones that also allow hands-free use.
Wireless Microphones Systems: The Basic Elements.
In this section we’ll take a look at the basic product elements that make up a wireless microphone system.
The phrase ‘radio mic’ tends to suggest some form of transmission and reception and this is indeed the case with wireless microphones. So we have a transmitter and receiver.
We’ll start with the receiver.
The above images show the front and rear of a typical wireless receiver. They come in many shapes and sizes. But most single channel receivers look something like this. This is where the signal from your radio microphone transmitter arrives and is then sent to the sound system. It’s important to remember that a radio microphone can be used with any sound system that a normal wired microphone can be used with. You just need a mixer or mixer/amp with a microphone input and the wireless system will work and sound much like a wired mic. You can see the 3 pin XLR output on the receiver. You can imagine that’s the XLR connector you find at the bottom of a wired microphone and just plug that into your sound system just the same.
You’ll usually find a bunch of controls on the front of the receiver and these rather depend on the type and complexity of the system, but for now it’s really enough to know that the receiver is where your microphone signals arrive once you sing or speak into the mic/transmitter.
Usually, there are external aerials to pick up the radio signals from the transmitter, these are sometimes fixed to the receiver, sometimes they are detachable.
The Radio Mic Transmitter:
The transmitter is where your radio signals are transmitted from. These are a little more varied, but there are two basic types. The handheld transmitter and the ‘beltpack’ transmitter. Beltpack transmitters have lots of names. They sometimes get called ‘bodypack’ or ‘pocketpack’ transmitters depending on the manufacturer and application, etc.
Here are two examples of handheld and beltpack transmitters.
The handheld transmitter is actually a combination of a microphone and a wireless transmitter so it combines the two elements into a single enclosure usually just a little bit bigger than a normal handheld wired microphone, and this item, alongside a receiver forms the basis of a complete wireless system.
The ‘beltpack’ transmitter is a transmitter only and requires a microphone or instrument to be plugged into it. These types of transmitters are used alongside ‘headset’ or ‘headworn’ microphone types, or small lapel mics, sometimes known as tie-clip or lavaliere microphones. Instrument mics such as clip-on brass/woodwind microphones or other miniature instrument mics can also be used and electric guitars can also be plugged in via a suitable cable.
One other function that the beltpack transmitter performs is to provide power to the associated microphone. Many smaller microphone types are condenser microphones and require powering. These are very small voltages that can be be provided by batteries within the transmitter, and sent from the beltpack to the mic via the same cable that carries the signal. This is one of the reasons why not all mics can be used with all transmitters. Different beltpacks have different connector types and may also use different wiring arrangements. So it’s crucial that the mic and transmitter are compatible.
Both types of transmitter will have some form of battery compartments to house the batteries that will power the radio electronics and the microphone (if required).
Microphones for Beltpacks:
The types and range of microphones that can be plugged into beltpack wireless transmitters is pretty vast. There are a whole host of microphones designed for use with wireless beltpacks. Headset, lapel, miniature instrument mics, etc. There are some examples below:
These types of microphones offer wireless and hands-free freedom to musicians, presenters and lecturers as well as vocalists.
Plug one of these mics into a compatible wireless transmitter with suitable receiver and away you go!
So these are the three basic elements of a wireless microphone system. Receiver, transmitter and microphone.
In the next part we’ll look deeper into wireless mic systems, looking at transmission types, frequency ranges, and phase locked loops! And what are the essential facilities and concepts that make some wireless mic systems better than others.
See you then.
As with all The Noizeworks blog posts, this information is provided on an informal basis. Every effort is made to ensure that the information contained within is correct, but we accept no liability for circumstances arising out of the piece and/or the ability to interpret it. etc…etc…