Music in motion pictures is an indispensable tool filmmakers utilize to effect the mood of their audience. It often gets underrated as a predominant psychological force as it is employed subliminally by filmmakers under their narrative so that their audience is unaware of its presence. Nicholas Cook, author of Analyzing Musical Multimedia, states, "words and pictures deal primarily with the specific while music deals primarily with responses--that is, with values, emotions, and attitudes ."(22). However, there is certain music that is suppose to be heard by the audience as part of the cinematic diegesis. All sounds that are understood by characters in the narrative are referred to as diegetic; however, those sounds that are not part of the diegesis are referred to as nondiegetic. This would suggest that diegetic music is processed on the conscious level while nondiegetic music might remain on the subconscious level (Gorbman, 75). Although many people might be unaware of these two types of sounds while screening a film, it effects their reactions, interpretations, and moods significantly.
The role of music in a motion picture is in direct relation to the level of ambiguity in a particular visual scene. The more ambiguous a scene is, the more filmmakers rely on their composers to develop a musical score that interprets the meaning of the scene for their audience. Therefore, music provides a cue for the listener to tell whether the narrative is suppose to be perceived as scary, romantic, funny, melancholy, or other-worldly--ultimately, affecting the audience's mood. Horror movies are great examples of that concept.
Hitchcock's brilliant masterpiece, Psycho (1960), is a perfect example of how a musical score can tell its audience what's about to come. The most memorable scene in the film was the brutal shower stabbing scene with Janet Leigh. The use of music in this scene allows the viewer to achieve a fear beyond total comprehension. As Leigh is showering, the audience follows a POV of Bates into her room. At this point, the music gets irksome, eerie, and scary. The audience knows the inevitable doom of Leigh's character because of the taunting music. When Bates stabbed Leigh's character to death, one of the most famous uses of diegetic sound in film history comes into play, as each stab sounds like shrieking violins--the famous "eeeh, eeeh, eeeh" that has been parodied in later horror movies.
Along with letting the audience know what's coming, music in motion pictures, according to Suzanne Langer, "creates an image of time measured by the motion of forms that seem to give it substance, yet a substance that consists entirely of sound, so it transforms itself. Music makes time audible, and its form and continuity sensible (53). Film music can cover up time discrepancies between real time and virtual time. The relative time that has passed in a movie can be expressed solely through music; through this medium, the cinema recreates our sense of reality--in essence, affecting our sense of mood.
An example of this...