How to Use Sound to Depict Theme in Your Documentary Film

In my previous blog, I stressed the importance of making deliberate filmmaking decisions to capture specific themes. Although I focused more on visual elements, I would now like to turn up the volume on the importance of sound. How you utilize sound is another critical choice that can allow your theme to shine through. Films are what we see AND hear, which means sound is 50% of your film. Do not underestimate the vital role of sound, especially when it comes to expressing theme.

One way sound can be exploited to depict theme is to consider it in symbolic terms. Normally when we think of symbols, we imagine physical objects or at least something we can see. However, sound’s special relationship with our auditory senses allows its various dimensions to be manipulated for the purpose of illustrating distinct concepts. Let’s look at a few ways this can be done in a documentary film.

Suppose you’re following a depressed subject through a park as you interview him. You capture the nearby laughter of children as they play. Maybe that laughter becomes increasingly isolated and louder as other ambient park sounds fade out. And maybe this occurs during a moment your subject reveals an awful truth from his childhood. In fact, you edit this scene to ensure that it does.

Then, you abruptly cut the children’s laughter and leave only the sound of your subject’s trembling voice as he recounts horrific past trauma. Then, perhaps, there’s an extended period of silence, something odd for such a busy park. We would infer that these sound editing choices serve as the symbolic death of the subject’s youth and innocence. Yes, the audience processes this idea through the subject’s words, but it’s also reflected through the inventive and symbolic use of sound.

In order to execute this properly, you would need the concept ahead of time which means considering theme early on in the process. This would inform both the setting of your subject’s interview as well as the supplemental sounds you’d want to capture. Again, articulating how these elements can function well in advance gives you a clear direction prior to loading gear into your mom’s minivan. Remember, just because you’re making a documentary doesn’t mean you can’t make certain decisions prior to production to help depict your theme. Themes may emerge naturally, but don’t count on it. Instead, deliberately construct them in a purposeful way.

Like film, sound has its own ability to function in terms of both content and form. That is, we can dictate both WHAT we’re hearing and HOW we’re hearing it. Or, as in the prior park example’s final moment, if we’re hearing it at all. When to utilize silence is also an important consideration.

Here’s another example of using sound to express theme. Maybe you’re making a documentary on one of those widely debated topics that never gets resolved. You are able to interview many subjects on all sides of the issue, but are looking for a better way to depict the fact that no one actually listens to one another; arguments always remain in a perpetual stalemate of shouting over one another.

With this theme in mind, you decide to construct a scene that includes a mash-up of audio from every interview. You present one audio clip after another, progressively building and overlapping these cuts into a cacophony of absolute noise with no one sentence able to be clearly heard and therefore not understood. The theme here, unlike the audio itself, would be clear: everyone prefers talking to listening and when everyone is talking, no one can be heard, and when no one can be heard, our problems cannot be solved. This is another example of how sound can be used symbolically to present a particular theme.

In my previous blog on theme, I mentioned how the lighting in Schindler’s List evolves as Schindler’s good nature reveals itself. Sound too can evolve in a similar way throughout a film by having its own auditory arc while perhaps that same arc is being presented visually. An example of sound achieving this same effect could be the following:

Let’s say you’re capturing a subject who is a hoarder as she attempts to de-clutter her house. In the opening stages of the film, the subject lives in an absolute mess, signified by boxes, trash, and piles of God-knows-what all over her home. You could choose to accentuate many sounds in the environment simultaneously in order to produce another sort of clutter, one of exaggerated or competing sounds from the messy house. In addition, the audio could be doctored to be a little more grating, rough, loud, and somewhat unpleasant for the audience.

As items are removed and space created, the sound could soften and also become “cleaner.” By the end, there could be minimal sounds that mirror the minimal mess. The added bonus would be that the audience would likely share in the subject’s feeling of cleanliness because they too would have experienced a sort of renewed transformation, albeit solely in their ears.

Sound plays a vital role in film and can be instrumental in expressing certain themes. Figure out what your theme is, then make decisions about how to utilize the components of sound to best express it. This will give you direction for choosing locations, deciding what to capture, and how to edit. Only then can you execute your vision with a purpose. Of course, it may not always be appropriate to use sound to illustrate theme, but at least it’s another tool in your filmmaking toolbox. Just remember, you heard it here first.