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Track 6 · Video2 min read

LESSON 26

Sound for video

The picture is only part of a video. Microphones, levels and the room.

WHERE A MICROPHONE LISTENS · FROM ABOVE

Three pickup patterns: a full circle for omnidirectional, a heart shape for cardioid, a narrow forward lobe for a shotgun microphone.

Which microphone

Microphones differ in how much they hear from each direction: omnidirectional all round, cardioid mostly from the front. Film and television wanted more directional microphones still; Electro-Voice brought out its shotgun microphone in 1963.

Get close

On a film set the boom operator holds the mic on a pole as close to the actors as possible without letting it into the frame. A lavalier clips to clothing, often hidden under it, and leaves the hands free; keep it from rubbing on fabric.

Levels

Set the recording level so the loudest moments stay below the top of the meter. Past it the signal clips: the tops of the waveform are cut off flat, and the sound distorts.

The room

Outdoors, use a wind cover. Before you leave a location, record a stretch of silence, the room tone, so the editor can smooth the cuts between lines. A clap on camera at the start of a take gives picture and sound one shared mark.

Try it today

  1. 01Film a friend talking, with the camera's own mic, from three metres.
  2. 02Film again with a lavalier, or a phone recording, on their collar.
  3. 03Record ten seconds of silence in the room.
  4. 04Clap once at the start of each take.
  5. 05Listen on headphones and compare.

Figures from Wikipedia, 'Microphone', 'Boom operator (media)', 'Lavalier microphone', 'Clipping (audio)', 'Production sound mixer', 'Presence (sound recording)' and 'Clapperboard', read 2026.10.16. The steps under Try it today are working practice, not a standard.