What is an L-Cut
It's a very good technique if you use it right. Such a transition can kill two birds with one stone — "hide" this very transition and give more information.
One L-Cut example is you are shown a character who is monologuing, and the following fragments show the subsequent/previous/present events, but the monologue is not interrupted. The character can be telling a story about his memories/dreams or just historical moments in the movie lore.
If the sound was "cut" along with the video during the monolog, it would be very strange and only irritate the viewer. By using L-Cut and J-Cut, we prepare the viewer for the next frame and provide a softer transition.
J-Cut is the opposite of L-Cut. You can hear the sound of the next scene, but see the picture of the previous one. It has the same goal — more information and smoothness of the transition.
These techniques are a part of the editing rule — don't trim audio and video in the same place. This will be very noticeable for both the eyes and the ears of the viewers. And so we disorient the viewer a bit with the smooth transition and prepare him for the next scene.
You don't have to "hide" the transition with the sound from the next shot — you can use music that will play in the background.
How to use L-Cut
The basic idea is to move the sound of the current clip into the next frame to create a smooth transition that overlaps with the scene that follows. For this you will need separate audio and video tracks, then you can merge them and adjust accordingly. The length of the sound overlay depends on the kind of impact you are looking for.
If you're creating a video montage with a voiceover, you'll need to place all the video clips one by one, dragging the audio to the point where you want the scene to end. You have the creative freedom to experiment with L-Cuts and trust us when we say editing your videos with this technique is fun.
You can also alternate the use of L-Cut and J-Cut to create a transition between different audio tracks. This will make the transitions look more natural. Try these simple cutting techniques in your projects. You'll find that this way your videos look much more professional.