If you're planning a live event and someone has asked for captions, you've probably run into two options that sound interchangeable but aren't. There's human CART captioning, and there's AI captioning. Plenty of articles online will tell you one of them is always better. The real answer is that it depends on your event, and choosing well can save you money on some sessions while saving you from a very public headache on others.
We provide both at Talon AV. Here's how we actually help clients decide.
What the two options really are
CART stands for Communication Access Realtime Translation. A trained, certified human captioner, either a stenographer or a voice writer, listens to your event and produces verbatim captions in real time, often at hundreds of words per minute. Stenography is a skilled profession, and a good captioner does more than transcribe sound. They handle context, jargon, crosstalk, and accents the way a human listener does.
AI captioning uses Automatic Speech Recognition, or ASR. It's the same family of technology behind your phone's dictation. Captions appear automatically from the audio, with no human in the loop. In some platforms it's quite literally a switch you flip on.
Both are useful. They just have different strengths.
The honest tradeoffs
Accuracy. This is where the real difference lives. A skilled CART captioner reliably delivers very high accuracy, even when the room is noisy, speakers overlap, or the content is full of technical, medical, or legal terminology. ASR has come a long way, but it still struggles with exactly those conditions: heavy jargon, strong accents, multiple speakers, bad audio. For a casual internal meeting, that's fine. For a keynote in front of a thousand people, a caption feed full of errors becomes its own kind of failure.
Cost. ASR is meaningfully cheaper, and for high-volume situations, like a dozen simultaneous breakout rooms over several days, the math often favors it. CART captioners are skilled professionals, and their time is priced that way. Where people get into trouble is treating cost as the only number that matters. The better question is what an inaccurate caption actually costs you on a given session.
Preparation. Both get better with prep, and this is where a lot of caption projects succeed or fall apart. Human captioners do their best work when they get speaker names, agendas, and industry terminology ahead of time, and they do even better when they can sit in on a rehearsal to get used to the speakers' cadence and accents. ASR systems can be tuned too. You can pre-load key terms and names to improve recognition. Either way, good captions are not a flip-the-switch-day-of accommodation.
Risk and the room. ASR runs on the audio it's given. Bad audio means bad captions, full stop. A human captioner can adapt mid-sentence to a surprise speaker change or an audience Q&A. A machine can't anticipate. On a high-stakes event, that adaptability is a big part of what you're paying for.
A simple way to decide
Match the method to the stakes of each session.
Human CART is usually the right call for high-profile, public-facing, or executive sessions like a keynote, a commencement, or a board meeting. It's also the right call when the content is dense with specialized terminology, when you have a formal accommodation request or a compliance requirement, or when multiple speakers and live Q&A make the audio unpredictable.
AI captioning is a reasonable fit for internal, informal, or low-stakes sessions. It works for high-volume content, like many breakout rooms over many days, where putting a human captioner in every room isn't realistic. And it makes sense when budget is genuinely the binding constraint and some captions are far better than none.
Here's the part most of the "always pick a human" articles leave out. You don't have to choose one for the whole event. You can put a human CART captioner on the general session and your highest-stakes content, and run well-prepared ASR across the breakouts. That's exactly what we did for Children's Miracle Network's Hospital Week: human CART in the general session, including the live musical performance, ASR support across the breakouts, and a full accessibility review afterward. The client got the accuracy where it mattered most and sensible economics everywhere else.
Getting captions onto the screen is its own job
One thing worth flagging, because it catches people off guard. Picking CART or ASR is only half the work. Getting those captions to show up accurately and in sync, on the in-room screens and on your live stream, takes dedicated systems and technical expertise. Broadcast-standard closed captions, CEA-608 and 708, in-room caption displays, captions burned into a stream, captions on a second-screen link, those are all different technical paths. The captioning method is the what. The caption delivery system is the how. A great captioner feeding into a broken display doesn't help anyone.
How we help
At Talon AV, we treat captioning as a production value, not an afterthought. We'll tell you honestly which method fits each part of your event, help you collect and organize prep materials for your captioning team, design the caption display and delivery systems for both in-room and streamed audiences, and build in the redundancy that keeps captions running when something goes sideways. We do this for our own clients, and as a specialty partner for other production and AV companies.
If you're weighing captions for an upcoming event, or you just want a second opinion on what your event actually needs, reach out for a consultation. And if you want the deeper technical picture, our Event Accessibility services page gets into CART, ASR, sign language interpretation, audio description, and assistive listening.