Wireless microphone systems are replacing traditional wired mics in many professional applications.
You'll see them in action in big arena concerts, theatre musicals, and non-musical applications like stand-up comedy and speeches.
This widespread use is a testament to the reliability of wireless mics. This also means that sooner or later, you'll be using one. So you need to have an excellent working knowledge of wireless systems to get the best use out of them.
Here I am going to be covering the essentials of wireless mics. This includes what they are, how they work, and why you should consider using them. I'll also help you discover which wireless microphone system is right for you.
What Is A Wireless Microphone?
Wireless microphones are also known by other names. This includes
- Cordless microphone
- Wireless mic
- Portable microphone
They all refer to the same thing, a microphone that works without a cable. Instead of a physical wire, it transmits audio signals over the air via a built-in transmitter.
The audio signal is sent via radio frequencies to a receiver, which routes the signal to a PA system or recording console.
How Wireless Microphones Work
Mics are transducers that convert one type of energy into another.
The specific energy they convert is sound. They convert acoustic energy into electronic signals. They contain a diaphragm that vibrates when sound waves hit it. The diaphragm moves a magnet near or within a coil, converting the sound waves into an electrical current.
This current traditionally passes through cables. But for wireless mics, the signal passes wirelessly via a transmitter.
Wireless mics encode the electric signals into carrier signals, which can be transmitted wirelessly. The receiver then reverts it to its original form.
The electronic signals are then amplified and processed. Then they are directed toward another transducer - the speaker. The speaker converts the electric signal back to acoustic energy, producing the sound we hear.
There are times when these electric signals are stored as data for later use. The layman's term for this process is audio recording.
Wireless Microphones vs. Wired Microphones
Many swear by the sound quality of wired mics. They continue to be widely used in recording studios, and there's no hint of them being replaced soon.
Physical wires are also the most straightforward and affordable solution for basic setups. But they do have limitations. Some disadvantages of using cables include the following:
- The length of the cable limits position and movement.
- Cables take up space and can be a trip hazard on stage and backstage.
- Wires are prone to physical damage, which can negatively impact audio quality.
Wireless technology frees you from being tethered and is very convenient. Especially for singers who are constantly moving around. But they, too, have downsides:
- Transmitter battery life can impact sound quality and operation stability.
- Prone to radio interference
- Mics with transmitters are less durable than traditional mics like the SM58.
For small-scale PA systems and basic setups, both mics are equally good. What you choose will ultimately boil down to preference.
Types Of Wireless Microphone Systems
The development of wireless microphone systems resulted in multiple types. Some of the most common ones include:
- Wireless handheld Microphones - These are the most commonly used. They look like a regular microphone sans the wire or cable, with the transmitter built in. They are meant to replace traditional wired handheld mics, mimicking their shape, polarity, and sound quality. Active singers prefer these types of mics—especially those who like to move around as they sing.
- Plug-in Wireless Systems - These are small transmitters that can be attached to the XLR port of a traditional mic. Once attached, the standard mic can now connect to a receiver wirelessly. This is a good option for those who want the freedom of being untethered while retaining the specific response of a traditional handheld mic. With this, you can make popular classic mics like the SM58 operate wirelessly. This also works great for vocalists who prefer the response of popular and familiar mics.
- Bodypack with Hands-free Mics - These are systems where the transmitter is housed in a bodypack instead of the microphone's body. The body packs are attached to the person's body, usually clipped to a belt. It then connects to handsfree mics like a Lavalier mic or lapel. These are attached to clothing near the mouth. Some look like a headset microphone and are mounted on the ears. This is perfect for singers who want to move their hands freely for singing and dancing. It's also the favorite of public speakers because it frees their hands for gestures.
While all three mics are often used for music, they are not limited to them. They are also used in sports, announcements, conventions, meetings, etc.
Parts Of The Wireless Microphone System
Much of the initial part of this article is already about the microphone component. So let's go straight to the point. The Microphone is what captures your sound and converts it to electric signals. Wireless systems are usually bundled with mics, and each one can be very different. So it would be best to look at the details before purchasing any wireless system package.
Wireless microphones with built-in transmitters are the most common. These are often handheld dynamic mics with cardioid polar patterns. A dynamic microphone captures vocals nicely, hence its widespread use.
Another common mic type you'll see are lavaliers and lapels. These are paired with a small transmitter that you can clip on. Public speakers usually use them, but musicians can also use them. They allow for hands-free operation, but given their compact profiles, they respond differently from a regular mic.
The Wireless Transmitter
Another crucial part of the wireless system is the wireless transmitter.
Wireless transmitters are either built into the microphone or attached to them. Which one you get depends on the type of wireless microphone system you are using.
The wireless transmitter is the device that transmits the signal by converting it into a radio signal. Without them, wireless microphones wouldn't be wireless!
Many wireless transmitters work up to 1,000 feet, but some factors can extend or reduce their range.
The frequencies of wireless systems are heavily regulated by the FCC (Federal Communications Commission). The aim is to avoid interference with other critical devices.
Many microphone transmitters work with ultra-high frequency channels (UHF). Some modern models operate in the 2.4 GHz range, similar to Wi-Fi routers.
All wireless transmitters run on batteries. So they share the same advantages and disadvantages as other battery-dependent devices. You always need to have a backup ready because low battery levels can impact sound quality or cause dropouts.
The Wireless Receiver
Another essential part of the wireless system is the wireless receiver.
Wireless receivers are devices that accept the radio signal from wireless transmitters. They need to work on the same radio frequency as the transmitter to receive the signals.
With UHF wireless systems, the frequency can vary, so you need to know how to match the frequency to the transmitter. Thankfully, modern wireless systems have automatic frequency selection, which makes it easier to set up multiple wireless systems in a single venue.
There are three types of wireless receivers. These are:
- Non-Diversity Receivers - These wireless receivers only have one antenna to receive signals. They are outdated, but you may come across one if you are using old tech.
- Diversity Receivers - These have two antennas instead of one. This helps avoid issues with poor signaling, as if one antenna fails to pick up the signal, the other one will.
- True Diversity Receivers - True diversity receivers also have two antennas. However, they are further apart and connected to separate modules. It utilizes advanced algorithms that intelligently switch to the antenna with a stronger signal. This helps reduce poor signaling issues and dropouts.
Wireless receivers don't always have to be mobile, so they are usually powered by mains. For best results, they should be placed in a spot with less interference and have an unhindered view of the transmitter. Wireless range should also be considered.
Analog Vs. Digital Wireless Systems
The main difference is in how they convert audio signals. Analog wireless systems compress the audio signal and expand them again at the receiver. A digital wireless mic system converts the audio into a digital signal instead.
Here are some other differences between these two wireless systems:
- Latency - Latency, or delay, differs between analog and digital systems. Analog has almost zero latency, while digital wireless systems can vary.
- Audio Quality - Analog systems compress and uncompress the audio signal. In telecommunications, this is called "companding." This can reduce sound quality, especially with cheaper analog systems. Digital wireless systems don't have this issue.
- Radio Frequency Performance - Analog and digital systems operate in the UHF band range. However, digital microphones work more efficiently in this space.
- This does heavily depend on the range you are working in. Many have automatic frequency selection.
Advantages of Wireless Systems
The first and obvious benefit is freedom of movement. You can move around without all those wires and cables shackling you to your amplifier or mixing console.
This means that musicians can put on more outstanding performances. Dances can be incorporated into the act, and singers can switch positions. As wires don't hold back musicians and singers, they can give their performances their all!
This freedom and flexibility also allow for a more straightforward stage setup and microphone placement.
The microphone can be set on stage anywhere as stage setup doesn't need to consider wire lengths, amplifier placements, etc. Instead, the microphone can move around on stage with the performer.
The lack of wires also makes them safer to use. Without any cables stretching across the stage, performers are less likely to trip or fall while performing.
There are also plenty of technical benefits to wireless mics.
If you've been using old cables, you'll immediately notice sound quality improvements when you switch to wireless. The shielding used on wires is prone to damage, and this can cause interference to seep through, resulting in a noisy signal.
Not having to deal with cables also means less maintenance and less stage clutter. And a clutter-free stage is very important in this age dominated by visuals.
Disadvantages of Wireless Systems
The biggest issue is battery life. Batteries power wireless transmitters, so you don't need a power cord. This lets you use it without being tethered to a power outlet, but it limits the duration of use.
Keeping track of your mic's batteries is best. The last thing anyone wants is for their mic to die during a performance.
Another disadvantage is its finite range. It would be best if you still stayed within range of the transmitter. And this range can be negatively impacted by physical obstructions, wireless congestion, electromagnetic interference, and even weather conditions.
The range of a mic typically comes down to the price. More powerful systems command a premium.
The last disadvantage is price. If you shop around online, you will find that wired mics are generally more affordable than wireless.
You will also need to purchase batteries and additional equipment for your wireless system. As a result, a wireless system typically costs more to run than a wired one.
How to Find the Perfect Wireless Microphone System
Finding the best wireless microphone system will boil down to suitability. You must consider what you're using the system for, the venue, and compatibility with your existing setup.
Below, I cover some crucial factors you should consider before buying a wireless mic.
Earlier on, I mentioned all the different types of microphones and how they are used. Stick to the kind that fits your situation. For vocals, best to go for systems with dynamic handheld mics. A lapel or lav mic will be great for public talks and speaking engagements. Voicing, sound rejection, and dynamic range will depend on the type of capsule used.
Size matters when it comes to wireless microphones.
Built-in transmitters are perfect for those who want to avoid adding another piece of gear to their overflowing equipment. More miniature transmitters are easier to work with but are prone to be misplaced and lost. Bigger ones can be annoying, but they usually have better battery life and are more sturdy.
Some receivers are larger than others. When working in darker conditions (like in a nightclub), a system with a larger interface will be easier to monitor and use.
Some systems are small and portable. They are perfect for on-the-go interviewing, podcasting, and speaking engagements.
Different wireless microphone systems will offer different ranges. These can range from just a few feet to hundreds of feet.
It's important to get the operating range right. Otherwise, the receiver won't be able to pick up your audio signal.
A good rule many sound technicians and performers use is to estimate the distance between the receiver and the microphone, then double it. This should give you a range greater than you'll need, but it's better to be safe than sorry.
Latency, or delay, is the time it takes for the signal from your microphone capsule to travel to the receiver. Ideally, you will want as short a latency as possible.
Think of it as like sound lag. Performances won't be great if the sound from your microphone is lagging behind the rest of your audio due to high latency.
So, when looking for the right wireless microphone for you, investigate the latency or delay of the microphone. Most performers will want a latency of at most ten milliseconds. The shorter the latency, the better.
Number of Channels
More channels are crucial for venues that utilize multiple wireless systems at once. You'll need two channels for the two mics for a typical band with a lead singer and a backup. Channel requirements will be higher depending on how many wireless mics you need to run simultaneously.
Wireless microphones tend to be more expensive than wired systems. Despite the benefits, this can make it difficult for some people to purchase a wireless system instead.
You should search around online for some excellent deals. Once a price drops, some good wireless microphone systems can be purchased reasonably.
Check out different departments and more than one shop or website. Sometimes, a small shop or lesser-known website offers excellent deals. Eventually, you should be able to find what you need at the right price!
It's all about research and patience!
Finally, we have battery life.
This factor is one many people often overlook, but it's one of the most important. After all, no one wants their microphone dying on them in the middle of a gig!
Smaller wireless microphones tend to have smaller (and shorter) battery life. Consider microphones with exemplary battery life.
Wireless microphones set you free from the shackles of cables and wires. They use a built-in transmitter in their wireless mic system to carry the signal to a receiver without needing a physical channel.
There are lots of different types of wireless systems and microphone styles. As a result, you need to carefully consider factors like sound quality, latency, and battery life to find the right wireless microphone system for you.
I hope this guide to wireless microphones has helped you understand them better. Now, you should feel more confident choosing the right wireless microphone system. Good luck!