Intercom Systems

For simple shows, there is no need for an intercom configuration specialist, however when the system is complex having an intercom configuration specialist allows you to set up your intercom system that fits the demands of your show.  It also means that any issues that arrive can be directly addressed and corrected.

Introduction

There are three primary manufacturers of sophisticated intercom systems:  Telex (formerly RTS) Clearcom, and Reidel.  Each offers matrix based intercom systems and can be integrated into most mobile, studio, and flight pack systems.  The Telex Adam and it's junior Cronus and Zeus Intercom systems are the most simple, but still require someone who is technically proficient in matrix intercom systems and their integration into video and audio components.

For very simple shoots, a two wire intercom system using a single intercom power supply is more than adequate.

Common terms used when discussing intercom systems are 2 wire or 4 wire.  These two intercom technologies are not interchangeable, but can be interfaced using special intercom adapting devices.  

Most consider 4 wire to be a "less noisier" and more flexible intercom approach, allowing for a better ability to deliver to a wider approach.  When using a matrix system it is based on a four-wire approach, plus data and requires intercom interfaces to use two wire devices, including RTS and Clearcom belt packs.

Intercom Power Supplies

Intercom Power Supplies are the Heart for all intercom systems.  The Power Supply provides the power and audio for all two or four wire systems.  With very few exceptions all intercom systems require at least one power supply and each power supply can deliver one, two, or three channels of intercom power depending on the brand and model.  (There are older Power Supplies that can deliver up to 6 channels, however, they are rare).

Each Power Supply is limited in the total number of user stations that can be driven, however, for most intercom applications this is rarely an issue.  Only when more than 20 beltpacks are going to be used will this be an issue for most power supplies.  Another consideration is the total length of cable used to interconnect beltpacks and two wire user stations.

Intercom Matrix

The Intercom Matrix is the brains behind sophisticated intercom systems.  These devices manage any and all intercom devices and allows the production to manage who hears what and even when. 

An intercom configuration specialist is required for these systems when 

Most mobile units have an intercom Matrix system and the truck engineer usually is very qualified for it's setup and operation.

But when multiple mobile units or the addition of remote production locations.

Matrix systyems are based on the 4 wire approach to intercoim systems.  This requires adapters to interface 2 wire to 4 wire systems

RTS Cronus Matrix

RTS Adam Matrix

User Stations

User Stations are devices that are typically "mounted into a console or rack that allow the user to communicate with others as programmed through a matrix or simple connection to a two wire system.  

The simple two wire intercom user stations are essentially panel mounted beltpacks, some with additional sophistication.

The more sophisticated Matrix User Stations give the user flexibility in communications with others on the intercom system or the on-camera talent through IFB Systems

RTS

RTS MCE-325 - Two Wire User Station

Belt Packs

Beltpacks are the simplest element of an intercom system, and come in single and two channel versions.  

IFB Systems

IFB (Interruptible Feed Back) are support devices for Intercom systems which allow on-camera talent to hear program audio with the ability of the producer and/or Director to interrupt the feed and speak to the talent.  These systems are most commonly integrated into the matrix through a User station Control point and in some Intercom systems through an IFB controller.

Wireless Intercom Systems

Like everything else in this world, intercom systems are going wireless, both in digital and analog forms.

Digital Intercom systems are the newest and offer clear communica5tions, however, the digital processing does add delay and can cause intercom conversations to overlap.  On occassion the digital systems can have digital chain breakdowns causing the communications to be partially or fully garbled.  This is usually rare, except in areas where the frequencies are close to or overlap nearly radio devices.

Analog systems offer clear, wireless communications.  

The newer intercom systems offer two channel and up to 4 channels of independent wireless communications.  This allows one base station to provide two groups with intercom communications, or communications between two departments directly.

All radio devices have range limitations and frequency interference issues.  Most digital and analog wireless systems claim to have up to 2,000 feet, however, realistically it is 500 to 1,000 feet of direct transmission.  If there are walls, structures, or miscellaneous items in between the transmitter and receiver the distance can be greatly less.

Intercom System Versus Walkie-Talkies

An Intercom system has some specific purposes versus a Walkie Talkie System.  An intercom system and wireless Intercom are best applied when there is a need to have multiple station communicate both independently and together.  

Walkie Talkies have greater range, however, they are subject to cross talk, frequency interference and range limitations.  A combination wired/wireless intercom system allows the user to communication between multiple stations simultaneously and is not subjected to frequency interference issues (except the wireless portion).