Capturing conversations: the modern microphone

Thanks to developments in a number of key areas there are microphone products now available that can solve some of the key headaches in enterprise use; primarily mic placement and set up, monitoring and maintenance and aesthetic considerations. Anna Mitchell reports.

Technology advances are easier to achieve than behavioural changes. Users of microphones will turn their heads, walk away, speak too close, too loud, too quietly or stand too far away. And, while people want to be heard, their focus should be on what they’re saying and not how to correctly address a microphone.

One development that is successfully battling what is sometimes dubbed “poor microphone hygiene” is the trend for manufactures to incorporate multiple microphone capsules into a product.

“Array microphone technologies detect and track sound sources which eliminates the inconvenience of setting up multiple gooseneck or radio mics in conference applications,” explains Malcolm Crummey, sales manager for the UK and Ireland at TOA. “The benefit to the user is they no longer have to worry about speaking directly into a microphone as with correct placement and control of the mic array their voice will be clearly picked up.”

Duncan Savage, systems group manager at Shure UK agrees and outlines the consequences of not considering audio quality: “Poor sound in meetings results in reduced focus on content, lower levels of concentration, listener fatigue and decrease in overall productivity. Array microphones make communication effortless by requiring less interaction with technology.”

Biamp Devio product Family

It’s something that Iain McCowan, DSP engineer for Biamp, partially puts down to developments in Micro Electrical-Mechanical System (Mems) microphones.

“These microphone elements have been in smart phones, tablets and laptops for the last five to ten years and now quality is improving so that they are suitable for conferencing applications. These are very highly calibrated elements. They are well matched to each other so it makes them useful for arrays and they are very small. Furthermore, it is easy to manufacture multiple units,” he explains.

The competitive field of consumer technology can be thanked for some of this development. “There has been an arms race between all manufacturers of smart phones and mobile devices to make their audio better. Mems microphone technology has benefited from that,” notes McCowan.

"A few companies have released more sophisticated microphone array products in the last 12 months and that will continue.”

He believes that this - alongside the rise in processing power and memory capacity - is joining other advances in microphone array technology to push the product group forward. “Beam forming and voice tracking are well established in research and the technology is well understood, but it’s only really starting to emerge to its full ability in products now,” he says. “A few companies have released more sophisticated microphone array products in the last 12 months and that will continue.”

Software and processing advances are providing other benefits too.

“Automatic Gain Control (AGC) means a speaker can get very close to the capsule without the volume really increasing,” explains Romano Cunsolo, director of marketing and business development at Xavtel Communications. “You will not be able to override the capsule or distort the sound. If you go further away and the microphone doesn’t detect any sound it tries to raise up the gain, but only to the point where there is no feedback.

“[In our Senator system] a mix-minus auto calibration unit calibrates every microphone to the highest gain before feedback and works in conjunction with our Acoustic Echo Cancellation (AEC). A speaker can go back 50 or 60cm and talk very low and you will still here them. But it will not create feedback.”

Specifically looking at AEC technology, Cunsolo notes recent advances made. “I have worked with AEC systems for 15 years and in the past DSPs were not really dedicated to handle AEC. Today we have chip inside [one of out products] that is 100% dedicated to perform for AEC.”

Jens Werner, portfolio manager for business communication at Sennheiser, is keen to point out that developments in wireless technology can improve meeting systems and speech intelligibility.

“[We are working on] license-free wireless technology working in the 1.9 GHz DECT and 2.4 GHz Bluetooth band,” he explains. “Having wireless enabled meeting devices allows for great flexibility of microphone positioning and can improve voice pick up drastically.”

Many of these technology developments are also addressing the need for systems that work without constant attention from skilled personnel.

TOA AM-1 array microphone

Werner notes: “Having a flexible beamforming microphone array eases the process of using it in different room applications like table meeting, presentation or group discussion. The mic configuration does not need to be adjusted for different applications while keeping an optimal microphone placement.”

“Once a system is set, levels adjusted, environmental conditions taken into consideration it very often runs ‘as is’ during an event,” says  Sandra Kellermann, conference business development manager EMEA for Audio-Technica.

“Of course ad-hoc adjustment can take place, but the fact is that this is seldom the case, as in the heat of the battle there is often not much time to fiddle with parameters and frequently there are not the skilled personnel to do so.

“Installers really need to consider how easy it is to ‘re-purpose’ a conference or discussion system in these days of mult-use rooms. Is a system going to allow for different types of meeting, enable easy set-up of different translation channels, record discussions and even be moved from one location to another without too much hassle?”

IT departments are increasingly taking responsibility for conferencing systems. When it comes to management their mind isn’t on ‘tweaking’ settings and sound levels. They are thinking of remote monitoring, the need to push out updates across and enterprise and ease of set up.

By controlling systems over Ethernet, Cunsolo points out that multiple units can be programmed and monitored at the same time.

“Traditional analogue microphone input devices are unable to be tracked by one central management system that provides reports on status performance and faults,” says Shure’s Savage. “Digital microphone systems provide an interface that can report status updates on operational health that limits downtime and provides remote monitoring of system status.

“Browser-based control software offers comprehensive remote monitoring and control of all settings and status parameters over the web, a corporate network or an AV local area network. Systems that provide compatibility with third party control and automation systems (such as AMX or Crestron) enable the creation of custom interfaces on touchscreen panels.”

Developing the right technology is only part of the job.

“The level of acceptance for poor sound quality in the workplace is too high,” argues Savage. “If you are communicating as part of a business transaction or charging an hourly rate for your time, effective communication is essential to fostering productivity and efficiency during your meetings and keeping costs to a minimum.”

So how can you tackle this?

“Frequently the biggest hurdle is to convince the end-user to provide the time for a proper demonstration and to hear the sound quality of a system,” continues Kellermann.

“An end-user (not an acoustic engineer or a professional AV installer) can determine the sound quality only by listening, which is obviously one of the bases for good sound intelligibility.

“Very often the end-users confuse the terms, ‘sound quality’ and ‘speech intelligibility’, but basically the message is – we can’t hear it well enough. And when demoing, it is always useful to have another sound system at hand to compare the two.

“Too often, buying decisions are influenced by spec sheets or price and users don’ think about audio quality, because it’s intangible and can only be experienced with a proper demonstration. So it’s up to installers to educate their customers that the most impressive system on paper will underperform if it doesn’t sound good – either by design or set-up. Education is very important in this market. “
“What good is a crystal clear 4K UHF 50ft image of the CEO giving an annual speech to investors if the audio suddenly drops out or is unclear?”

“The biggest challenge as always is budget,” agrees TOA’s Crummey. “Audio seems to be treated with less importance compared to video or signal management and routing, even lighting! A picture may be worth a thousand words but not in AV presentation and conference applications. What good is a crystal clear 4K UHF 50ft image of the CEO giving an annual speech to investors if the audio suddenly drops out or is unclear? Audio systems, from microphones, to speaker systems, even room acoustics needs to be given more and at least the same through, planning and budget as the visual aspect in AV.”

Start by asking questions is Biamp UC product manager Rob Houston’s advice. “What is the organisation doing? What are they trying to do? What are their needs?,” he says. Armed with this information a better case can be made for good audio if conferencing is relied on by the company.

If a company is using conferencing to talk to global clients then audio plays a huge part in how that company is perceived. Houston argues that bad audio on a conference call can create a bad first impression in the same way as a dilapidated entrance would to visitors to a premises. “Why would you risk that?” he asks.

You can read full interviews with everyone who participated in this feature below:

Iain McCowan, senior DSP, Biamp Systems
Duncan Savage, systems group manager, Shure UK
Sandra Kellermann, conference business development manager EMEA at Audio-Technica
Jens Werner, portfolio manager for Business Communication, Sennheiser
Malcolm Crummey, sales manager UK & Ireland, TOA 
Romano Cunsolo, director of marketing and business development, Xavtel