Diegetic and non diegetic sound in horror films

Research : The importance of sound in Horror films


Sound is often overlooked in films but it is often the single most important element in setting the mood for the scene. Music has the ability to set the tone for how events will unfold. 
The effective use of music will help promote even more emotions to the audience. Even though there are allot of diverse range in the music that has been used throughout different horror films, some of these common conventions include: 

Using isolated instruments just before a key event occurs, this helps portray the vulnerability of a character in danger
Long suspenseful notes often help contrast with short, sharp notes to help shock the audience
Extreme intentional changes in pitch tones. For example long notes will suddenly change to sharp, high pitched noises. This is most notable in the film psycho; where the killer stabs his victim in the shower



There was an example of non-diegetic sound, however the use of character voices can be essential in the build of suspense in horror films. The characters voices would be heard by the others so it is diegetic sound. Characters who hide their faces throughout the film build up more suspense.

Diegetic and non diegetic sound in horror films

Diegetic sound is any sound created from a source within the world of the film. Non diegetic sound is sound that comes from outside the story.
Non diegetic sounds used in horror movies can be very effective as it can create a very eerie and suspenseful atmosphere for the audience, and diegetic sounds make scenes in the film more realistic.

This is the opening to Jaws, a very famous horror/thriller movie with an iconic soundtrack. Diegetic sound is used when there is a party. The sound of people chatting, a crackling fire, music and singing are example of this, and these certain sounds create a very relaxed, calm atmosphere, which contrasts with the horror of this opening scene, thus making it more shocking and horrific for the audience. The non diegetic soundtrack used throughout the film is used to signify when the shark is approaching. This builds suspense and indicates that danger is coming, striking feelings of fear and alarm.

Psycho has a very different take compared to the opening of Jaws, as there is no non-diegetic music at the start, Instead, there are only the diegetic sounds of the shower curtain being pulled and the water flowing into the bath, making the scene seem very realistic, which is effective as the more realistic it is, the more scared the audience feels. Rather than having dark non diegetic music build up suspense as the killer's silhouette appears behind the curtain, there is only silence (along with the sound of water) until the curtain is pulled and the killer attacks the victim. This is where the non diegetic sound comes in, high pitched, shrieking violins with sounds of the knife plunging into the victim's body. This approach is more likely going to make the audience jump and feel shocked and alarmed.