GUIDE
What is a simultaneous interpretation system? From booth and headsets to QR and phones
In three sentences
- A simultaneous interpretation system is the technical and human arrangement that carries a speaker’s voice into other languages almost in real time and delivers it to listeners; the classic version uses booth, interpreters and headsets, the new one uses AI and the attendee’s own phone.
- In AI simultaneous interpretation, speech becomes text, is translated in context and is spoken again with a natural voice; attendees scan a QR code, choose a language and listen without installing an app.
- The real delay is 3–6 seconds including the network; human interpreters also speak 2–6 seconds behind — a sub-second “instant” promise does not fit the nature of the task.
Say “simultaneous interpretation system” and most people picture a booth at the back of the hall, two interpreters and a box of headsets. This guide explains that classic setup, the new AI-driven one and where they honestly differ, using VerbaStage as the worked example.
The classic setup: booth, interpreters, headsets
In a classic simultaneous interpretation system the signal from the sound desk goes to a sound-proof booth; two interpreters alternate; the interpretation is distributed by infrared or radio and every attendee receives a headset. Its strength is the human interpreter’s sense of meaning, tone and culture. Its weaknesses are logistics and cost: booth setup, distributing and collecting receivers, two interpreters per language, separate equipment per hall. At a multi-hall fair or a one-day seminar this often costs more than the interpretation itself.
The new setup: AI and the attendee’s phone
In an AI simultaneous interpretation system the speaker’s voice is taken directly from the stage mixer and passes through three steps: speech becomes text instantly, the text is translated in context, and the translation is spoken in the target language with a natural voice. The result reaches attendees’ phones as one live broadcast per language. Attendees scan the event QR code, choose a language in the browser and listen with their own earphones; nothing is installed, no device is handed out. Audio and live captions are delivered together. Audience size scales the broadcast, not the interpretation cost.
Delay: the honest figure is 3–6 seconds
In every simultaneous system the interpretation trails the speech, because a correct translation needs a complete unit of meaning. For human interpreters that is 2–6 seconds. In the AI setup, with processing and network added, the typical total from mouth to ear is 3–6 seconds. VerbaStage states this figure as it is and has it measured in the hall during the event rehearsal; “sub-second” promises do not enter its marketing.
What the stage needs
With an AI-driven system the stage side becomes simple: a field computer taking audio from the mixer output or an authorised customer computer, stable internet and the event-specific capture link. No booth, receivers or charging stations. The operator decides which source is on air — stage or Q&A microphone. Before doors open, a rehearsal runs on real devices; the broadcast is not opened without seeing the venue network, audio and captions on a phone.
Q&A and multiple halls
A congress stage is not one-way. Questions come from the floor in other languages and the speaker must hear them in their own language. In a good system the stage language is always an open return room: the question is interpreted into the stage language and the answer is broadcast to every selected language. With seven seminars at one fair or events in several cities on the same day, every broadcast must keep its own identity, team, languages and archive. That is why VerbaStage creates a permanent event per hall under one program; QR, listener, operator and capture links are ready the moment the event is created.
Which setup for which case?
Where speed, scale and cost matter and the broadcast is mostly one-way, the AI setup is strong: seminars, product launches, fair stages, multilingual congress sessions. For legal, medical or high-stakes negotiation content, consider human interpreters or a mixed setup. Rehearse with your own content to decide; VerbaStage states this boundary openly and evaluates it together in the rehearsal.
Frequently asked
- What does an attendee need?
- A smartphone, their own earphones and Wi-Fi or mobile data. They scan the QR code, choose a language and listen; on supported phones playback continues with the screen locked.
- How many languages are supported?
- Thirteen spoken (source) languages are recognised today; target listener rooms are offered in English, French, German, Spanish, Arabic and Turkish; more are enabled per project.
- How natural is the voice?
- The goal is a natural narration that fits the speaker’s emotion; a copy of the voice is not promised.
- What happens to my data?
- Event data is separated by event and authorization scope; transcripts, recordings and feedback are kept only for the period and choices defined in the event agreement.
Instead of reading, listen: a live demo with your own voice.
Start a short live demo with a few details and microphone permission; see the delay, audio and captions on your own phone.
Last updated: 2026-08-18. This guide describes real product behaviour; figures follow our realism principle.