Microphone wireless system turns audio signals captured by microphone into radio signals. Then the wireless mic receiver captures the signals that are transferred from the transmitter through the air and return them back to audio. It allows the target sounds to be transmitted wirelessly. There may be much for you to learn if you are new to it. What to look for in a microphone wireless system? When will it be used? How to choose a best one? Let’s dive in and get the answers.
Wireless microphone system components
In general, wireless lavalier microphone system comprises three parts, which is totally different form the corded microphone.
Typically, a wireless system will feature one of three mic types.
It is the typical and standard microphone that comes in the type of condenser or dynamic. It is in the shape of streamline with a transmitter built in its body and preferred by stage performers, reporters, etc.
As its name suggests, it is worn on the head over your ear. You can adjust the arm to make the capsule stay close to the mouth at a suitable distance. It is helpful especially when you are in noisy environment or keeping moving.
Lavalier microphone, also called lav or lapel mic, is designed to clip on your collar without being noticed thanks to its small and unobtrusive body. It is commonly used in scenarios when a visible mic doesn’t satisfy the context or hands free is a must.
Within a microphone wireless system, audio wireless transmitter conducts the task of audio signal transmission to receiver. There are typically three types.
Handheld microphone transmitter
As aforementioned, wireless handheld transmitter is included in the mic’s body and is is powered by battery. As a result, the microphone is bigger than traditional one to some extent. It converts audio to radio signals, which are broadcast from the antenna.
Plug on wireless transmitter is stand-alone device that can convert most corded microphones to wireless. It connects to the model's lower section, which is normally attached to a cable.
A wireless transmitter belt or body pack is used when using a hands-free microphone, such as a headset or lavalier. It is in the size of a deck of cards. It can be tucked into a pocket or clipped onto a belt or waistline.
The receiver for wireless microphone system receives the radio signals from the transmitter and turns them back into audio. It is connected to your recording equipment like camera. It comes in three main types.
- Non-diversity: It uses one antenna to gain the wireless signals. Usually high quality receiver doesn’t adopt this type since it may cause dropout with only one antenna.
- Diversity: Diversity wireless receiver has two antennas that both connect to the same receiver. If one antenna captures weak signals, the receiver can turn to the other one, which enables a stable signals transmission. However, chances are that it may weaken strong signals.
- True diversity: Two separate antennas are utilized in true diversity wireless microphone system and each connects to separate receiver module. The receiver will tell which gains the better signals and selects the better one, which reduces the chances of audio dropouts.
Besides the receivers mentioned above, there is also wireless plug in receiver without visible antenna. This kind of receiver is compact in size thus offering great convenience to mobile recording.
Common uses of lapel microphone wireless system
Wireless microphone system boasts great advancement in the following uses.
Filmmaking, Broadcasting and Streaming
Microphone wireless system, especially the one with lav microphone, is favored by filmmakers, broadcaster and streamers. They use it for various reasons, and the most important is that it keeps the frame clean without a handheld microphone blocking the line of sight.
Obviously you can capture sounds with various microphones. Why does wireless lavalier microphone system stand out? It enables the microphone to stay close to the talents, eliminates the risk of tripping over and offers clean look with a discreet microphone.
Another benefit of WMS is that it allows free movement, which is incredibly necessary in education environment. It allows teachers and lecturers to move freely, making students better engage in the class. It is beneficial not only in classroom teaching but also for online class. For example, a fitness instructor wireless microphone system is light, causing no burden when the instructor do actions like stretching the body.
Wireless microphone kit is able to free the hands, which meets the demands of a lot of stage performers. Since they are hand-free, they can sing and dance and make better interaction with audience. Additionally, wireless headset mics enable flexibility of movement and decrease the chance of tripping over cables. It can also simplify the complexity and size of cable looms and runs for large-scale shows.
Table: Advantages and disadvantages in uses
We can get the benefits of microphone wireless system from the examples of application. And the following table shows both pros and cons for you to acquire better understanding.
|Discreet capsule for clean look and neat frame||Likely to be interfered|
|Free movement within the transmission distance||Dead spots exist where WMS won’t work|
|No risk of tripping over messy cables||The whole system fails once one component goes wrong|
|Hands free with lav or headset mic|
|Durable without cable that may be worn out|
How to choose the best wireless microphone system?
First, decide on the types of wireless microphone technology
Analog VS Digital
Generally, digital wireless microphone system is recommended. It outweighs analog in the following aspects.
Sound quality: Digital system converts sounds into electrical signals as 1s and 0s, which are stable and won’t be influenced. The analog system, however, transfer sounds in the form of modulated radio wave, which are easily interfered and result in poor audio. Moreover, the dynamic range will be compressed by compander, causing the degradation of the audio signal, which is easy to notice in cheap analog unit.
Long battery life: On average, digital system can last 40% longer because it has the lower power requirement of the transmitter.
Security: The transmission is encrypted so the transmission is secure and there is no risk of eavesdroppers in digital system. However, analog signals can be captured with a suitable receiver.
[For more information, check the article Why go digital: analog vs digital wireless microphone?]
VHF VS UHF Bands VS 2.4GHz
VHF: Short of very high frequency, VHF is at the range between 49 and 216MHz. To get the best performance, it is better to be 169MHz and upwards. If you want to record high quality sounds within a decent range and run single microphone wireless system, VHF is your best choice.
UHF: UHF wireless microphone system falls at 300MHz and above. This spectrum is less crowded in many countries, so it is feasible to run multiple systems at the same time. Therefore, UHF is ideal for getting excellent audio quality, operating more than one system while you have high requirement on transmission distance.
2.4GHz: This system is legal in almost every country in the world so you don’t need to worry about the international spectrum policy anytime and anywhere. Additionally, 2.4GHz wireless microphone system is easy to match the transmitter and receiver, which saves the time of setup. If you are eager for a user friendly system, it will be your first choice.
Second, consider the following factors to make further choice
These are the things you need to consider.
Microphone Type: From the aforementioned part we know that there are 3 typical types of microphones and each is suitable for different situations. Think about your recording content and place then you can get the one that is for you need.
Wireless microphone transmitter: This is also related to your shooting requirements. Do you need to be hand free? Is it better to be smaller? Just think about this questions before you make a decision.
Receiver connector: Receiver is directly connected your recording device, so it is necessary to take the connector into consideration. Generally speaking, a totally matching connection is the best choice. For example, if you use your smartphone to make the film, a wireless receiver for phone which features a Type-C or Lightning connector can be the top choice.
Range: Transmission range is differed from one microphone wireless system to another. It is advises to consider how far your recording device is to the sound sources and then look for a system with double range. In most cases, the higher the price is, the greater the transmission capability is. So going for one that perfectly fits your need is a cost-effective choice.
Size: There are variable sizes of wireless microphone systems on the market, from ultra compact size of a card to large desktop kits. Compact system plays a big role when you take outdoor recording frequently or need something unobtrusive. If you utilize it in the fixed place like classroom, a larger one with controls and screen allows easy operation.
Battery Life: Battery life is an important factor to consider for rechargeable wireless microphone system especially when the shooting lasts for a long time. Check the product specification list to see if it can finish a complete shooting for you. But pay attention, battery life usually has something to do with size and range so you should consider them together and decide which is the most significant for you. For example, if compact construction is your top need, you may reach a compromise on battery capacity.
Latency: The signal transfer leads to the latency in digital wireless system. Remember to check the time of latency and make sure it is within your acceptance.
Third, think about the frequency agility if filming places is changed frequently
In this circumstance, there are two types. Fixed-frequency wireless system means that it operated on one preset band while frequency-agile one can select an open channel. If you want your WMS to work in more places, a frequency-agile system will be good for you. In addition, it is useful when multi-person recording is needed since it reduces the chances of interference.
However, for two-person recording, there is another user-friendly choice. Dual channel wireless microphone system are now for sale, allowing running two microphones at the same time.
Three tips to make microphone wireless system sound better
After shopping for a wireless transmitter and receiver kit, you need to master some knowledge to make it record professional audio. Below we list three tips.
Get your mic closer to the receiver to reduce noise
A short distance between the mic and the receiver for wireless microphone results in strong signal transmission and better audio. Generally, all environments are full of radio waves that emitted by various electronic devices like computers. Chances are that there will be signal interference thus causing noise. Therefore, it is advised to isolate your wireless signal and direct it to the receiver.
Avoid blocking the signal
Maintaining a line of sight between the wireless transmitter and receiver also makes sense. If you want the microphone to work at its best, stay away from huge things like walls and metals. Most critically, if at all possible, avoid huge crowds. This is due to the fact that the human body is mostly made up of water, which absorbs RF radiation. Consider putting the receiver and transmitter in the same room, then elevating them above other obstacles and the audience for the greatest results.
Select appropriate batteries
Use rechargeable batteries made exclusively for the audio wireless transmitter whenever possible. Make sure the batteries are of good quality, preferably disposable lithium or alkaline ones. These batteries provide nearly the most consistent output voltage, which aids in signal quality. If the voltage is too low, it can cause sound distortion.
In this article, we talks about the components of microphone wireless system, the uses, the tips to find a suitable one for you and how to improve the system performance. Naturally, there are more topics that we can discuss about it. But at least now you have a idea about what it is and which can be best fit your needs. So you can have more choices the next time you invest in a microphone.