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Habla Espaol? Parlez Vous Franais? Sprechen Sie Deutsch?

Language interpretation is becoming more and more important in the business world. How SI applies to you and your installations.

Habla Espaol? Parlez Vous Franais? Sprechen Sie Deutsch?

Sep 1, 2001 12:00 PM,
By Jarrod Esposito

Worldwide collaboration in business is here to stay. Many companies have realized that the speed and extensiveness of global communications systems enable cooperation with foreign businesses. But although communication systems are in place to support worldwide conferencing, language remains a barrier for many companies. Few are the CEOs who can speak the native languages of every country they’d like to deal with, and even crash courses through Berlitz may not suffice.

Enter the simultaneous interpreter and simultaneous interpretation equipment. These systems make it easy to communicate in many languages at once with very little lag time. There are two keys to providing accurate interpretation at an event. First, a proper simultaneous interpreter with adequate knowledge of the subject matter and the required language pair is essential. Second is proper simultaneous interpretation equipment. The scope of the project and the interaction between participants determines whether a portable system or an installed system with interpreter booths would be best.


Audio equipment specifically designed for simultaneous interpretation is available for every type of meeting or conference, from mobile facility tours to boardroom discussions and conferences with hundreds or even thousands of participants.

Most facilities do not require permanently installed interpretation equipment. A permanent system has limited use, a significant cost and various equipment requirements. On the other hand, for temporary installs, there are rental companies that specialize in providing the right SI solution on a conference-by-conference basis. Although temporary SI use is more common than permanent installation, audio consultants, system designers and installers of systems within conference facilities should at least make sure that the means for integrating temporary SI equipment is built into permanent A/V systems. I’ve had to work in new, “state-of-the-art” boardrooms with countless bells and whistles, but without a way to provide an audio feed to the simultaneous interpretation system. This can be easily avoided if the designer or consultant is aware of the possible interpretation needs before installing the equipment.

Let’s look more closely at these most prevelant temporary systems.


A portable interpretation system is simply a wireless belt-pack transmitter and microphone for the interpreter and enough wireless belt-pack receivers and earphones for each participant. The transmitters use FM transmission and operate in either a wideband or narrowband modulation. Wideband transmissions inherently have better audio quality; however, narrowband transmissions have better interference rejection and the ability to operate over multiple frequencies within the same general area.

Most portable interpretation systems operate between 72.1 and 75.9 MHz (called the 72MHz band), or the newly released 216MHz band. These frequencies are allocated by the FCC for language interpretation, tour guides and assistive listening. While the 72MHz band offers a theoretical range of 1500 feet (300 to 500 feet in the real world), the 216MHz band offers double the range. However, the 72MHz band offers better sound quality and the ability to use more channels in a specific area without cross-talk.

Use of Portable Interpretation Systems

A portable interpretation system is ideal for situations where a simple but effective language interpretation solution is needed. Since these systems are wireless and battery operated, they are ideal for:

  • Multilingual tours of factories, manufacturing plants, museums, hospitals or other facilities
  • Small, informal escort interpretations
  • Short, multilingual events with limited budgets
  • Events where one-way (such as English into Spanish) is required
  • Depositions, hearings and other court proceedings
  • Religious events that provide bilingual services
  • Wherever a cost-effective solution is required.

System Setup

A key benefit of portable systems is their ease of setup. It’s one of the reasons that interpretation systems are now being used in situations that previously have gone without. The system consists of four basic components:

  • A belt-pack transmitter for the interpreter (battery operated)
  • A lapel or headset microphone for the interpreter
  • A belt-pack receiver for each participant
  • Earphones, headphones or neckloops for each participant.

To set up the system, attach a lapel microphone or headset microphone to the interpreter’s transmitter. Attach the headphones or ear pieces of the participants to their receivers. When the interpreter’s transmitter and the participants’ receivers are turned on, and frequencies or channels match, whatever is spoken into the lapel or headset microphone is heard in the participants’ earphones.

Because the system is wireless, the interpreter can be located at a distance from the participants either trailing behind a tour group or on the side or in the back of a conference facility. The interpreter should be situated so that he or she can hear the meeting clearly (near a P.A. speaker), but unobtrusively enough not to distract the participants.


This system is cost-effective and extremely versatile. Modern systems have multichannel transmitters and receivers, so finding a clear channel in a given area is rarely a concern. These systems can also select either wideband (better audio quality) or narrowband (better interference rejection) on the same receiver. Portable systems offer a range of options that can be configured for virtually any type of event.


The portable interpretation system, although very flexible, does have its drawbacks. It is designed for one-way interpretation and does not handle back-and-forth conversations between participants and in different languages, thus eliminating the possibility for extensive question-and-answer sessions or relay interpretation. Therefore, this type of system is best for situations where there will be little interaction, as in short meetings, mobile tours and presentations where the audience mostly listens.


Interpretation needs can grow and become complex. Let’s look at the common aspects of all interpretation systems to get some ideas about how to design an effective solution. Simultaneous interpretation systems can be divided into three functions: collection, interpretation and distribution. Each aspect of an interpretation system will vary depending on the intended use, the scope of the conference or the client’s needs.


Step one is to identify what the SIS needs to interpret. Is it the words of a single presenter using a wireless mic or a more complex dialogue that uses a conference system including many mics, phone lines and A/V sources? Once it is determined what needs to be interpreted, a design goal can be set.

Most permanent installations are part of a more elaborate A/V system, so incorporating an SIS poses some interesting concerns. For one, interpretation requires the interpreter to listen to distinct audio, preferably from only a few individuals at a time, without background noise such as ruffling papers, side conversations and other extraneous noise. This can be tricky, because most systems are designed so that all microphones can be left on at once. Events that require head-table discussions must use either a conference system or table microphones with an operator riding gain. This is also true of events with a hollow square setup, U-shape, classroom setup or any situation with multiple microphones. Note that hanging choir microphones, PZM mics and desk PZM mics typically provide audio that is acceptable for sound reinforcement but not suitable for interpretation. The trick is to collect only what needs to be collected — side noise gives interpreters headaches.


In this phase, the SIS takes the floor language or original program and distributes it to the interpreters. Systems can be designed and configured for bilingual events or for as many languages as are needed. The majority of the events held in the United States have six or fewer languages, whereas conferences held in Europe typically have eight or more.

Let’s say a conference has three languages: English, Spanish and Japanese. Since interpreters generally work with a language pair, such as English-Spanish or English-Japanese, it may be difficult to find an interpreter that understands and speaks all three languages. This is especially true when languages vary widely. It could be possible, for example, that no Hebrew-Bantu-Aleut interpreter exists in the world, should one ever be needed. For this reason, interpretation systems use what is called relay interpretation.

Relay interpretation allows our sample conference to be interpreted from the floor language, Japanese, into English via the Japanese-English interpreter, and then from English into Spanish by an English-Spanish interpreter. When designing a system for more than two languages, relay interpretation is a necessity.

How Interpretation Works

The floor language audio comes into the control unit. The control unit distributes the floor language to the interpreters unit. The interpreters unit is typically situated in an enclosed interpreter’s booth that allows them to work within the conference room, but in an environment that’s physically, visually and aurally separated from the audience. This allows interpreters to work free from distraction while concentrating on interpreting the audio from their headsets. Typically, an interpreter isolation booth accommodates two interpreters working within a language pair. Conferences with multiple languages require the use of separate interpreter booths for each language.


Once the conference proceedings are interpreted, the languages need to be distributed to the conference participants. Distributing the various languages can be accomplished via a wireless medium such as RF or infrared, or in a hardwired fashion via a delegate conference system. One of the more popular distribution methods in the United States is over FM radio signals. For conferences requiring several multilingual meeting rooms, extra security or confidentiality, infrared is the better choice.

To partipants, these three phases — collection, interpretation and distribution — are transparent. All they hear is a real-time translation of the speaker in their ears.


Let’s look at the benefits of the three distribution methods. FM-based systems are an excellent means of distributing multichannel audio from an interpretation system to the participants of a bilingual or multilingual conference. Each language can be assigned a different frequency, and participants can tune in to the audio channel for the language they wish to hear. As mentioned above, the FCC has allocated the 72.1 to 75.9 MHz and the 216MHz frequency bands for SIS use.

Most FM systems offer single-channel transmitters. These transmitters can be set to any of the available frequencies, but one transmitter must be used for each conference language. For example, if a conference is in English, French, German and Spanish, four FM transmitters must be used. The transmitted language is broadcast much like a small radio station. The participants receive the transmitted audio via a battery-operated receiver and earphone.

FM systems offer easy setup, excellent audio quality and cost effectiveness to multichannel distribution needs. To distribute audio, a small FM transmitter is connected to one of the outputs from the interpretation system. The audio is modulated onto an FM carrier frequency. The signal is transmitted via a transmitter-mounted antenna or remote antenna. A single transmitter/antenna combo can transmit a signal capable of covering a small hotel conference room or an arena holding tens of thousands of people. Because the signal is RF, it will travel around corners, through windows, doors, floors, etc.

Receivers come in a variety of configurations from single channel units to 57-channel receivers. Some are designed to receive only one type of transmission (wideband or narrowband), while others can receive both. Receivers also vary in function. While some offer only an LED indicator, others are fully programmable and offer digital readouts for channel selection, signal strength and battery life.

Uses for FM Systems

Due to their lower cost (compared to IR Systems), easy setup, excellent sound quality and signal durability, FM-based systems are ideal for:

  • Conferences with conservative budgets
  • Conferences held outdoors or in heavily sunlit rooms
  • Conferences requiring less then 10 interpreted languages
  • Meetings that are not of a confidential nature
  • Where fast, easy, reliable setup is essential.

FM-based systems have become the standard for conferences in the United States. With careful frequency selection and a quality system, the distributed audio will reach the participants clearly and reliably.


Infrared systems work much the same way as FM systems. The only difference is that the audio signal carrier uses infrared light instead of radio frequencies. Infrared systems are a line-of-sight medium — just as you need to point an IR remote control at your television. IR systems are the standard in Europe and in countries that do not have an FCC-type organization allocating transmitted frequencies.

Some of the original infrared systems used carrier frequencies between 55 and 1335 kHz. Using 40 kHz of separation and narrowband modulation, up to 32 channels can be transmitted in a given location without channel cross-talk. Most systems are configured for up to 12 channels. And due to interference problems at 255 kHz with newer indoor lighting systems, many IR manufacturers are using higher carrier frequencies, up to 3.8 MHz. Interference with lighting has been eliminated with the newer frequencies. However, systems with more than four channels — and those with the newer frequencies — have not been embraced by all manufacturers. In addition, older and newer systems are incompatible, which makes it more difficult to add to existing systems.

Uses for Infrared Systems

Due to the transmission medium, transmitted audio remains within the reception area. This feature of an IR system can be a benefit over FM. Infrared systems are better used where:

  • Multiple meeting rooms within the same facility need to be outfitted with multichannel interpretation
  • Meeting proceedings are confidential
  • More then 10 channels of interpretation are required
  • Outside radio interference is an issue because of local RF congestion.

Although generally more expensive, infrared systems provide a solid transmission medium without the risk of RF interference. Due to their setup parameters, IR systems are not available in portable form, nor can they be used outdoors (due to the wide frequency of infrared light emitted by the sun).

Infrared System Setup

Infrared systems operate by modulating the audio (multiple channels or languages) via a transmitter onto a coaxial cable. The FM signal carried by the coaxial cable is then demodulated into separate carrier frequencies of infrared light by an emitter panel. The infrared light is picked up by the receiver and converted back into separate audio channels. Because infrared systems are line-of-sight, it is imperative to cover the entire conference room with the infrared signal. Balconies, dead spots and obstructed areas can be covered using multiple emitter panels. Emitter panels vary in size and output power. Covering an entire meeting room and eliminating dead spots can be tricky and expensive.


An alternative to distributing audio via a wireless means is to use a hardwired approach. Hardwired systems are available either in a permanent installation or as portable systems. They can accommodate a microphone and interpretation device within one unit or as listen-only devices, incorporated into the arm of an auditorium seat. Delegate units can be fixed units within a conference table. The delegate conference system is usually designed for smaller groups, 60 or fewer, although they can accommodate 100 or even 10,000.

The delegate unit provides a microphone and interpretation for every participant at an event. In this way, meetings can be interactive with a lot of back-and-forth conversations between participants. The ideal setups are those where participants have a desk surface in front of them to accommodate the interpretation equipment.

A portable delegate conference system is compact enough to set up in any conference or corporate facility, with or without an installed audio system. The collection phase of the system occurs through the delegate unit microphones; the interpretation aspect through the control unit and interpreters unit; and the distribution aspect through the delegate unit earphone, channel selector and volume control.

Uses of Delegate Systems

Due to their total integration of all three components of an SIS plus miking capability, these systems are ideal for:

  • Conferences that have interactive conversations
  • Board of directors meetings
  • Conferences where ultimate security is required
  • Classroom training sessions
  • Panel discussions and multi-microphone events.

Delegate conference systems can also be used in conjunction with a wireless distribution system for flexibility in providing the proper simultaneous interpretation equipment for any conference situation.

Interpretation systems have become a an important part of making multilingual meetings successful. Since there are many types of systems geared for many uses, there is no longer any reason to exclude anyone from understanding.

Where Does SI Apply?

What types of events require interpretation? The meetings and conferences requiring simultaneous interpretation vary widely:

  • Any court proceeding with foreign defendants (depositions, EBT, trials, etc.)
  • Board of director meetings of multinational corporations
  • Educational seminars with foreign teachers or students
  • Sales and product-introduction meetings for foreign clients
  • Religious events
  • Meetings of global non-profit or non-government organizations
  • Plant, factory, hospital, facility, museum or stock exchange tours involving multinational participants.

There are many more applications where simultaneous interpretation equipment can be implemented. Based on current trends in global communication, the use of simultaneous interpretation will probably continue to grow.

Jarrod Esposito is president of Global Equipment Network Inc., online

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