Actual Sound
Actual sound is any sound that originates from within the world of the film. The more common and precise industry term for this concept is diegetic sound. A sound is considered diegetic if the characters in the story can, in theory, hear it. This type of sound is crucial for building a believable and immersive cinematic world. It grounds the audience in the reality of the scene. Diegetic sound includes all the dialogue, sound effects, and music that are part of the story’s environment.
The World of the Film (The Diegesis)
To understand diegetic sound, one must first understand the concept of the diegesis. The diegesis is the total world of the story. It includes the characters, the settings, and the events that take place. Therefore, any sound that logically belongs to this world is diegetic. If a character in a film turns on a car radio, the music that plays is diegetic. The character and the audience both hear it. This sound is part of the scene’s “actual” reality.
Types of Diegetic Sound
Diegetic sound can be broken down into three main categories.
| Dialogue | This is the most obvious form of diegetic sound. It includes any speech spoken by the characters on screen. |
| Sound Effects | This category covers all the sounds made by objects and actions within the story. Examples include footsteps on pavement, a door slamming shut, a gunshot, or the rustling of leaves in the wind. These sounds are often recorded separately by a Foley artist and added in post-production. However, they are still diegetic because their source is visible or implied within the scene. |
| Environmental Music | This is music that is part of the setting. It is not the film’s score. Examples include a song playing from a jukebox in a diner, a live band performing at a party, or music coming from a character’s headphones. The characters can hear this music, and it often influences their actions or mood. |
There is also internal diegetic sound. This is a special category that includes a character’s internal thoughts or monologue. While other characters in the scene cannot hear these thoughts, they originate from within the character’s mind. Therefore, they are considered part of the story’s world.
Diegetic vs. Non-Diegetic Sound
The opposite of diegetic sound is non-diegetic sound. This is sound that comes from outside the world of the story. The characters cannot hear it. Non-diegetic sound is an artificial layer added for the audience’s benefit. The most common form of non-diegetic sound is the film score or soundtrack. This music is used to heighten emotion, build tension, or signal a change in tone. A narrator’s voice-over is another common example of non-diegetic sound. Filmmakers use both diegetic and non-diegetic sound together. They combine them to create a rich and complex audio experience that is both immersive and emotionally powerful.
