Popular across a range of commercial installations from schools, hospitals, concert halls and places of worship to broadcast studios and boardrooms, microphone technology has advanced considerably in recent years.

Jason Grbevski, Audio Products Group‘s Biamp Systems and Revolabs product manager, says this is particularly the case with wireless technology.

“With the advent of unified communications systems and the requirement for great control over AV technologies, wireless microphones are
becoming smarter, networkable devices. Systems such as the AKG DMS series and the Revolabs HD Executive systems allow control systems to interrogate the microphone receivers for information such as battery status, mute status or even provide ‘out of range’ alarms that can
then report back to room management systems and facilities staff,” he says.

“A common scenario in a corporate space would be to alert the receptionist that ‘your microphones are not in the charging dock’ via an email at the end of the day, helping users to ensure that the microphones are charged and ready for use in the morning.

“With the advent of digital transmission mechanisms and digital signal processing, wireless microphones can now also provide secure encrypted transmissions that are sonically superior to the systems of old. Internal processing within the receivers and microphone
transmitters allows for easier commissioning and implementation in difficult acoustic environments.”

Audio Products Group TOA product manager Peter Cleary says ease of use for the end user makes wireless the most popular microphone choice across a range of installations.

“Wireless microphones allow the user to move more freely about the room than a cabled option will. They come in two types, handheld or belt pack. The beltpack option consists of a transmitter unit which is worn by the presenter and connected to this is a microphone which
can be either a tie-clip type or a headset.

“The primary advantage of using a wireless system is that you are not bound by cabling to designate where your system must be. You can install a receiver unit in the most out-of-the-way location to keep the customer happy and the installation clean while giving the microphone user maximum flexibility and freedom of movement.”

While this adds freedom to an integrator’s installation, the strength of signal must be well considered, he adds.

“The strength of signal must be great enough to penetrate walls or have the ability to transmit over longer distances. If need be, this can be achieved with external antennas and boosters compatible with certain models.”

Wireless solutions are also ideal in situations where cables simply can’t be run, such as heritage-listed properties.

Audio Products Group offers the TOA range of wireless products designed for basic public address situations such as clubs and schools, as well as the more high-end AKG range which is more popular with the stage and performance sectors. Both ranges work at varying
frequencies and have extensive antenna accessory options to fit various applications. The company’s Revolabs range consists of small digital systems primarily designed for the corporate boardroom market. Designed to be discreet, these products can interface with tele or video conferencing systems.

Syntec Australia manager for installed products Gary Foster agrees that wireless technology is by far the biggest seller from the company’s Sennheiser range of microphones.

“Wireless products are very popular in schools, commercial venues and for artists. Presentations become more lively when the presenter has
the freedom to move and keep a close link to his audience. His voice can be understood no matter where he is and what he is doing, so he can underline his statements by moving to exhibits, showcasing the details he is describing. Wireless tecnology is also easy to handle and reliable in operation even for non-technical users.”

Easy linking to the audience is another of its key advantages, Gary adds.

“Wireless microphone technology allows the presentation to be continued in the audience. It is simple to integrate the audience for discussion through wireless audience microphones.”

Sennheiser’s key product in this area is the Evolution wireless system. Products in the range include clip-on microphones, headsets – a viable microphone alternative in diffi cult acoustic situations where there is a lot of uncontrolled noise in the presentation room or when there
is a risk of feedback – and handheld microphones. New system features include automic auto-tuning to prevent HF interference, enhanced frequency bank management and optimised charging.

The system also boasts highly sensitive receivers and complex fi ltering to avoid interference from other wireless links.

The wireless microphones are compatible with a wide range of selected frequencies. All units operate on low-congestion UHF transmission spectrum.

ALL WIRED UP

There are three broad categories of wired microphones: handheld models used for vocal or speech applications; installed microphones
such as gooseneck lectern models used in churches and function rooms and boundary layer microphones used mainly in boardroom applications; and broadcast microphones used in the recording, radio and TV industries.

Peter says these products have applications in installations where wireless technology may prove limited.

“The limitations of a wireless system depend on the particular product range and how ‘frequency agile’ that product is. Products at the lower
end of the market may come with a fixed frequency or a small number of frequency options, meaning a lower number of systems in the one place. The further up the range you go themore options you get, therefore the more systems you can implement.”

Jason says it’s a matter of weighing up the pros and cons of a wired installation.

“The advantages of a wired system are likened to bricks and mortar. Wired mics provide secure, low latency, long distance operation that is immune to any RF issues that wireless mics may experience. Often this also translates into a cost benefi t over wireless or active technologies.

“On the other hand, wired microphones by their nature provide a limited amount of ‘play’. In a multi-function space where a room may be used for a board meeting in one instance and to host a product launch in another scenario, a hard wired solution would prove far less flexible as a system engineer would be required to cater to every practical combination. This may involve multiple patch points or floor boxes installed around the space that then need to be mixed, selected and processed somehow.”

Gary says cabled microphones are most popular in boardrooms, courtrooms and other more traditional installations. In this case unobtrusive
gooseneck style ‘out of sight’ microphones are often selected.

“Slender gooseneck mics are unobtrusive and allow the installer to place the microphone heads close to the speaker. Other popular wired products are ceiling microphones and boundary layer microphones. These suit ‘out of sight’ spaces where you don’t want to see the microphones at all, such as in a church. Ceiling microphones hang from the ceiling for use by choirs or bands and provide unobtrusive high sound in cases where nearly invisible sound pickup is required.”

Wired products can also be combined with accesssories such as stands for anti-vibration and suspension to reduce noise from the table, floor or rostrum.

Choosing between wired and wireless requires careful consideration of the requirements of the people who are going to be using the system, Peter says.

“For example, a microphone system that is used occasionally by the local sports club will be completely different to the setup required by the
local performing arts centre. Both of these examples would probably use product from wireless ranges but the requirements would be totally
different. The sports club would use only one or two transmitters (microphones) and would therefore only require two receivers, whereas
the performing arts centre would potentially use multiple microphones with capsules suitable for vocal use.

“The technologies used by the individual market are governed by the needs of the particular sector and can quite often draw on a broad cross section of available technologies. For example, in the education market the requirement can vary from a simple classroom application which may consist of a basic wireless setup utilising a tie-clip wireless microphone to a performance based system in a multi-purpose hall which uses both cabled vocal microphones and wireless presentation setups.”