Narrated description track for visually impaired viewers — plays in dialogue gaps. Professional voice talent, precise timing, never competes with dialogue.
To dub precise visual descriptions during dialogue pauses — that is the core task in audio description. You sit in the edit suite, have the final cut in front of you, and must decide: Where are the gaps in the sound design large enough to accommodate a second voice without it competing with or disturbing the dialogue? That is the first technical hurdle. An amateur thinks you can just describe everywhere. A professional knows: timing is everything.
The voice actors for audio description tracks are specially trained — neutral vocal tone, clear articulation, moderate tempo. They are not allowed to interpret, not to emotionalize, not to compete with the film. Instead, they describe what is visually essential: cuts, changes of location, gestures, facial expressions not conveyed by the dialogue, image composition, colors if relevant, shot sizes. In a close-up of a distressed face during silent moments — you describe tears, tension, direction of gaze. In an establishing shot of an abandoned train station, you describe architecture, time of day, mood. Your words must fit within the framework the film provides.
In the production process, you sit with the director, and later with a dedicated audio description editor — this role doesn't exist everywhere but is firmly established in professional houses. You mark the pauses on the timeline, you write the script, you test the rhythm. A 90-minute film can receive 1500 to 2500 words of descriptive text — no more. Every word must work.
Technically, the audio description is mixed and bound as a separate audio track — either as a secondary track in mastering or as a standalone version, depending on the distribution channel (cinema, streaming, TV). For cinema mixes, care is needed: the description track must not compete with the cinema's ambient volume but must be clearly audible. Many streaming platforms now offer audio description — the implementation works more simply there. You ensure the track remains synchronized, that levels are consistent, and that no errors slip through.
It is not an artistic gimmick, but accessibility as a technical duty — and at the same time, a quality test: If you can describe a film so concisely that a visually impaired viewer fully understands the plot, then you have understood what is visually important. This sharpens your eye as an editor and sound designer.