J-cuts are used when editing footage to have the audio from the next shot precede the video. J-cut is not short for jump cut. The name actually comes from the shape a j-cut makes on your editing program’s timeline. Using a J-cut or an L-cut is all about keeping the flow of the edit moving without getting boring. If a J-cut or L-cut is performed correctly, then the audience will never notice it taking place.
J-cuts are a common yet powerful editing technique often used by professional editors. It is a type of split edit, which is a transition from one shot to the next, where the audio and video transition at different times.
Because they help maintain visual continuity, split edits are often used as transitions between shots within scenes rather than using transition effects such as fading (also called melting) or wiping.
An L-section is when the sound from the previous scene continues to play on the footage of the next scene, the J cut is the opposite of the L cut. Examples of the most iconic J-cuts/L-cuts of all time; We can show director Stanley Kubrick's 2001 movie A Space Odyssey. He uses both techniques perfectly.
Both L cuts and J cuts consist of three things:
(1) Primary shot video,
(2) Primary shooting sound and
(3) B-roll or other video clip.
Depending on how these three elements are arranged, we can create either an L-cut or a J-cut.
For more information about video editing programmes you can read our article;