Today's intercom systems are high-tech.
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What could be more fundamental than communications in an industry where individuals collaborate to create compelling content? But don't make the assumption that intercom systems are not high-tech these days. We have come a long way since the era of carbon microphones and Western Electric headsets, and what is fundamental is that function has not changed, only the sophistication with which we attack the technology. Of course, this is largely due to tools that simply were not possible in the early days of television production. It is, however, remarkable that we still plug headsets into the backs of cameras and use gooseneck microphones on rack-mounted communications panels as the user interface for communications just like we did more than a half-century ago.

Two drivers are largely responsible for the wholesale change in communications underlying the user interface mentioned above.

First, in the latter part of the 20th century, around 1970, a method was developed of using a duplex two-wire (actually three-wire) system for party-line communications that carried power along with the audio. Party-line communications was nothing new, and in fact was the basis of telephone communications for about 100 years before RTS and Clear-Com improved on the approach.

Around the same time, flexible systems were developed that used active and passive audio hybrids to allow effective communications on multiple party lines at the same time without joining all of them together. This development of the “matrix intercom system” may have had even more far reaching impact. Every control room today is built with private matrix communications channels for different parts of the crew to communicate selectively instead of using one large party line system. I am sure this saves many productions from devolving into chaos. It also allows problem solving to move on in private when it might otherwise have to wait for a quiet period. Best of all, matrix systems allow things to be centralized that otherwise would require multiple overlapping and redundant systems.


Take, for instance, IFB. IFB can be built without a matrix system and was done that way from day one in permanent studios. But by connecting talent earpieces through a matrix system, the production staff needs to have only one microphone for communications. Using software-definable systems for switching the audio signals allows them to be routed flexibly for monitoring, with interrupt or noninterrupt outputs easily created. It is the routing, né matrix, aspect of systems like this that make highly flexible and powerful systems possible. Many modern systems also adopt digital displays for control panels, which allows signals to be named uniquely for each production — for instance, labeling the IFB for the anchor with his name instead of tape labels or fixed electronic labels.

Sports and live production

Nowhere is this more important than in major sports production. Indeed, much of the advancement of matrix systems, and in particular the highly flexible control and programming systems that have evolved, are a direct result of systems designed to support the needs of major sports and location entertainment show production.

I had the fortune to work in that segment of the industry and saw the rise of an “A2” position whose responsibility was just communications. On large productions it is a full-time, high-pressure position. Over time, it has grown to be a complex part of a production as well. Major productions, like the Academy Awards, spend months planning every part of the installation of communications, which includes multiple production units for domestic and international program distribution, as well as facilities to support single-camera standups (with IFB) for affiliates around the world. Every department in a large production needs private, though overlapping, communications, including lighting, audio, producers, director's “camera” circuits, engineering channels and more.

Wide area systems

But there are applications today that are far more technically interesting and that make use of more complex digital transport mechanisms. Large, distributed broadcast organizations have complex communications needs. I was first introduced to wide area systems like this when I started a 30-year association with Eurovision in the late '70s. Even then, Eurovision (the European Broadcasting Union's “operations” arm) maintained a four-wire communications system that had drops in every control room in Europe that originated or received shared signals. At that time, it was analog and hard to keep levels balanced. Today, Eurovision, and any large operation, particularly those doing news production from many interconnected sites, have a crying need to connect local matrix intercom systems into a vast WAN intercom system that facilitates complex live breaking news production.

Solving this thorny problem today is made considerably easier by the ability to connect matrices together digitally to form a huge virtual matrix. Audio is often connected as VOIP trunks, and IP-based control systems allow configuration of complex productions without involving personnel in each site. It is possible to pass mnemonics for labeling panels, configurations of who can speak with whom, even mix minus selections for IFB to be flexibly built with only modest preplanning. Web-based programming permits graphical representations of the topology as well as simple Web service calls for some operations. Leveraging IT technology for voice communications is not unique to media operations, but the immediacy of our industry puts particular stress on systems for quality of network service and guarantees of service availability. The PSTN can always be a backup, but relying on voice circuits would severely limit the flexibility we have come to expect from modern communications.

I find it interesting that in an era of smart phones and wireless everything that we have not more fully adapted communications technology to wireless approaches. That is not to say that wireless intercom has not been available for a long time, for it has. But why aren't we using Bluetooth headsets instead of tying ourselves with copper leashes? Perhaps we give camera people a touch screen to adjust volume and mute their mics, or flash the name of someone calling a camera on a smart OLED tally indicator. Why not allow forwarding a call to an absent operator to their smart phone over Wi-Fi within the facility? A little creativity might make the sophistication of today's communications technology look simplistic in the future.

John Luff is a television technology consultant.

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