www.duran-audio.com

Clearer understanding from Duran Audio

Dutch loudspeaker manufacturer Duran Audio, selling products under the brand name AXYS, is a company strongly based on research.

The company was founded in 1981 and over the years has developed a unique line of loudspeaker products for use in public address/voice alarm systems and within the entertainment industry. Over the last decade the company have become better known for producing digitally controlled loudspeakers which have solved a major problem facing airports the world over, having clear, understandable messages from the Public Address/Voice Alarm system.

What is speech intelligibility and why is it important?

The purpose of an announcement through any PA system is to communicate a message. An email with half the words missing would be viewed as an unacceptable form of communication. An unintelligible PA system is no different!

In modern airports it is no longer acceptable for the PA system to just be loud enough - it also needs to be intelligible

Speech Intelligibility refers to the understandability, comprehensibility, clearness and subjective quality that the person listening experiences.

With the arrival of digital audio we are all now used to crystal clear audio both at home and on the move. This has set a new benchmark for quality. People now expect the same quality from a PA system without fully appreciating all the problems that exist in large spaces. The science of sound, acoustics, is not a simple subject, the larger the room/space and the larger the system then the more difficult it becomes to maintain the quality.

In addition to this increased expectation from the public very few public address systems are now installed. Most systems are now public address/voice alarm systems that form part of the fire alarm/life safety system. With this comes regulations and minimum standards for intelligibility. When it comes to life safety then the most important factor is the Intelligibility of the system. The quicker people understand the instructions being given to them then the quicker they can act upon them, the safest system is a system where the announcement is understood the first time it is made.

The quest to improve speech intelligibility

In the early 90’s Duran Audio recognised that the speech intelligibility of PA systems in airports, railway stations and other large public buildings had not improved since the early 70’s. In many ways it was becoming increasingly difficult to design intelligible sound systems. Several factors contributed to this but two clearly stood out:

• The trend amongst architects was moving towards very large open rooms/spaces with clean finishes and high light levels. This resulted in rooms/spaces with hard surfaces and long reverberation times (Lots of echo).
• There had been little improvement in loudspeaker technology in this market area.

The Intellivox is a digitally controlled loudspeaker which focuses the sound where you want it

Having identified the problem Duran Audio set about seeking the solution. The ideal solution soon became a reality in the form of the AXYS Intellivox. The Intellivox is a digitally controlled loudspeaker which focuses the sound where you want it, at the listener. In visual terms it can be thought as a spot light as opposed to a flood light. Intellivox loudspeakers have a very narrow vertical coverage angle and a very wide horizontal coverage angle. In large reverberant spaces this type of loudspeaker has many benefits:

• The sound is digitally aimed at the listener
• There is less sound reflected from walls and ceilings therefore you hear less echo.
• It is highly efficient at distributing the available power from the loudspeaker
• The volume of the loudspeaker is the same if you are close to it as it is up to 60 metres away

The result is a very natural, clear and direct sound which is essential for achieving the required levels of speech intelligibility and getting your announcement understood.

Practical and architectural considerations

Another benefit is that a single Intellivox has the capability to cover an area of over 6000 m2. The result is that just a few units are needed to cover even the largest arrival and departure halls. This results in a significant reduction of the true installed cost of the system whilst at the same time delivering the highest level of speech intelligibility possible.

Due to the digital control it is not necessary to physically angle the loudspeaker

Due to its slim line unobtrusive design the Intellivox can either be integrated into the architecture of a space as a simple, unobtrusive vertical element or it can be made into a bold statement. Giving the architect the freedom to integrate the Intellivox into the building design rather than see it as a necessary but unwanted feature within the building. Due to the digital control it is not necessary to physically angle the loudspeaker thus enabling it to be recessed into walls or columns, mounted directly onto a wall or integrated into another architectural element; either way it is possible to make the Intellivox virtually disappear. Colour matching to any décor is of course also possible.

Reference sites

The Intellivox was the world’s first commercially available digitally controlled loudspeaker array and since its introduction has been specified to solve the problem of speech intelligibility in large highly reverberant spaces. Intellivox installations can now be found all over the world in a variety of applications including transport hubs, places of worship, parliaments, atriums and museums. References include The Louvre (FR), Grand Central Station (US), Dubai Airport (UAE), The Milano Dome (IT), JFK Airport (US), Paddington Station (UK), and The German Chancellors Office (GE).

Info:
Duran Audio BV
Koxkampseweg 10
5301 KK Zaltbommel
The Netherlands

T. +31 418 515583
F. +31 418 518077
E: info@duran-audio.com
W: www.duran-audio.com

 

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