Diegetic and Non Diegetic sounds

Diegetic Sound

Sound whose source is visible on the screen or whose source is implied to be present by the action of the film:

• Voices of characters 
• Sounds made by objects in the story 
• Music represented as coming from instruments in the story

Diegetic sound is any sound presented as originated from source within the film's world, Diegetic sound can be either on screen or off screen depending on whatever is source is within the frame or outside the frame. Another term for diegetic sound is actual sound. 

Non-diegetic Sound

Sound whose source is neither visible on the screen nor has been implied to be present in the action:

• narrator's commentary 
• sound effects which is for the dramatic effect
• mood music          

Non diegetic is represented as coming from the source outside the space.


The distinction between diegetic and non-diegetic sound depends on our understanding of the conventions of the film viewing and listening. We know that certain sounds are represented as coming from the story world, while the others are represented as coming from outside the space of the story events. A play with diegetic and non-diegetic conventions can be used to create ambiguity (horror), or to surprise the audience.