Nonfiction Sound and Story for Film and Video

A Practical Guide for Filmmakers and Digital Content Creators

Amy DeLouise, Cheryl Ottenritter

• Publisher: Focal Press
• Year: 2019
• Print ISBN: 9781138343085
• eBook ISBN: 9780429799822
• Topic: Media & Performing Arts
• Subtopic: Film & Video

This book guides nonfiction storytellers in the art of creatively and strategically using sound to engage their audience and bring stories to life.

Sound is half of film and video storytelling, and yet its importance is often overlooked until a post-production emergency arises. Written by two experienced creators—one a seasoned nonfiction producer/director with a background in music, and one a sound designer who owns a well-regarded mix studio—this book teaches nonfiction producers, filmmakers, and branded content creators how to reimagine their storytelling by improving sound workflow from field to post. In addition to real-world examples from the authors' own experiences, interviews with and examples from industry professionals across many genres of nonfiction production are included throughout.

Written in a conversational style, the book pinpoints practical topics and considerations like 360 video and viewer accessibility. As such, it is a vital point of reference for all nonfiction filmmakers, directors, and producers, or anyone wanting to learn how to improve their storytelling.

An accompanying Companion Website offers listening exercises, production sound layout diagrams, templates, and other resources.

1

Sound Basics

Sound is essential to storytelling. Good sound propels us through a narrative, triggering certain emotions, reminding us of themes, and helping us recall information. Along with the visuals, sound creates a satisfying film experience in both fiction and nonfiction stories. When the sound isn’t right, we know it. The wrong music can ruin the mood for a scene. An interview that echoes becomes distracting if we can’t see a large space in the shot to justify the echo. A soundtrack with too prominent a drum track intrudes on important words in an interview. In each of these instances, the story is disrupted, rather than supported, by sound. By contrast, when sound “works,” we often don’t notice it. We laugh, we cry, we absorb important information—all without realizing the role that sound has played in making us respond. So, what is it about sound that makes us either jump further into the story or get pulled away from it? What are the components of sound that are essential to storytelling? In this chapter, we will demystify some of the physics of sound and explain some resulting principles and best practices that you can apply to your sound production, editing, and mix. Whether you are working as a solo storyteller or collaborating with a large production team, this basic knowledge of sound will help you improve your media making and ensure that audio is a strong part of your work.

Sound Waves

Let’s start off with the sound wave. Sound is created by vibrations caused by pressure and release in the medium that surrounds it. These compressions and rarefactions can cause movement through air, plasma, liquid, or even solids, though typically it is air. This repetitive action of compression and rarefaction forms a pattern that is called sound waves. In the field, we record sound waves from two main sources: “sync” sound—those sounds that are synchronized with picture, including dialogue—and “wild” sounds—those audio elements we record independently of picture. We then take those sounds and convert them from the analog world in which we listen and live to the digital realm in which we produce our films. Though analog recordings can still be made, today digital recording is the norm. In post, we mix those gathered sound waves together, often weaving them with other already-recorded sounds, such as music and sound effects. During playback, the digital sound files are converted back from data to analog, which is the way the sound waves arrive at our ears. The result is a story you watch and hear, hopefully without noticing our handiwork (Figure 1.1).

What’s interesting is that we often don’t think of sound in physical terms. But these waves really do have a physical presence, just one we can’t see. For example, low frequencies have very long sound waves. At 50 Hz, the sound wave is over 22 feet long. Imagine four refrigerators stacked on each other end to end. No wonder low frequencies can travel further. And no wonder they build up in small rooms. But we’ll get to that in our production chapter. For now, just imagine all of the sound waves surrounding you and bouncing off of you in every space in which you move.

FIGURE 1.1 Graphic of compressions and rarefactions of a waveform.

Frequency or Pitch

Pitch is almost entirely determined by the frequency of a sound wave, essentially the speed at which it travels. In the International System of Units (SI), one cycle per second of frequency is called one Hertz, named after the person who discovered electromagnetic waves, Heinrich Rudolf Hertz. A sound that is 20 cycles per second is 20 Hz. One that is 4000 cycles is often referred to 4 kilohertz, or 4k. (Note that this has nothing to do with 4K footage, which has to do with pixels.) When you are making a recording, you need to know that any vibrating object creates sound. Wherever you are filming, there are many other frequencies flying around besides what you are focused on recording. They might complement the primary sound you are recording. Or they might compete with it. Understanding what kind of frequencies you are trying to isolate can help you with microphone placement. For example, since low frequencies travel further than high ones, it is easier to hear a male with a low booming voice than a small child with a higher voice (unless it’s your kid, in which case you could pick that sound out of a lineup anywhere; Figure 1.2).

Every sound also has overtones, undertones, and harmonics beyond the fundamental frequency. Overtones add depth and range to the sound being recorded. When you record, you want to minimize the amount of change to all of these frequencies. This is especially true with the human voice, with its many overtones and undertones. Because the human voice has such a wide frequency range, and is very complex, you can really negatively impact the voice by manipulating frequencies too much when you are recording in the field. We will address all this later in Chapter 4 on location sound.

FIGURE 1.2 Graphic of sound wave over time depicting pitch.

What this also means for the video storyteller or filmmaker is that there are sounds beyond your primary audio that can interfere with your recording. Be aware of the sound around you. To do this, we recommend always using professional headphones (not earbuds) when recording sound. You will hear sounds much more clearly through headphones. You’ll be able to place your microphone slightly differently for clearer primary sound, or understand before it’s too late just how distracting a particular sound in the background will be to your primary audio. It’s always better to rid your location of the noise—shut down that humming air conditioning unit, move the snuffling dog—rather than fix it in post. Or avoid interrupting frequencies altogether by using our sound scouting tips. But when you can’t avoid competing sound waves, you do have options (which we’ll address later) for minimizing or eliminating some disturbing frequencies in either production or post.

Amplitude

Amplitude is the measure of energy of a sound wave. It is measured from the top to the bottom of the sound wave. The more energy or amplitude, the louder the sound and the further it travels. If you open the door to a night club on a Saturday night, chances are good that you will physically feel those powerful waves of sound washing over you. The pressure you feel and hear is measured in SPL, or Sound Pressure Level. Distance is also key in measuring SPL. For instance, a vacuum cleaner is loud at 70 SPL just a little over a yard away. A jet plane is 140 SPL at 54.5 yards away. Last summer, I measured the SPL around our community pool with my handy analog SPL meter to determine how loud our swim meets were from various distances, including the house of a person who complained these gatherings violated a local noise ordinance. Let’s just say there was a lot of sound energy, but no laws were violated.

Amplitude is measured in decibels, or “dBs” for short. Sound engineers like me often think of dBs as “clicks” or small levels of adjustments: “bring that music down two dBs” or “bring that sound effects track up a click (or one dB).” By the way, like the Hertz, the decibel is another term in audio that gets its name from an important inventor. In this case, the “bel” refers to Alexander Graham Bell, who studied how sound travels, invented the telephone, and helped launch the audio engineering field with his pioneering work (Figure 1.3).

FIGURE 1.3 Sound wave showing amplitude, pointing out crest and trough.

Measuring Audio

If you want to be precise, there are many ways to actually measure dBs. One of the most common is dBFS, which is the Decibel Full Scale used in digital audio systems. The dBFS is sample based and, in digital audio, has a top level of zero. In analog, there is actually sound beyond the top of the scale, or over zero. But we’ll stick with digital for now. Digital audio that hits zero will distort. When recording, it’s best to stick around –10 to –12 dBFS to give plenty of headroom. Final delivery levels can vary from –10 to –6 dBFS.

Another way to measure audio is Decibel True Peak (dBTP). dBTP refers to the inter-sample peaks that can be created during the conversion back from digital into analog and is a measurement used predominantly in broadcast media. However, we are seeing this specification now in online media delivery, too.

Yet another way to measure sound is LKFS or Loudness, which is K-weighted relative to Full Scale. Like SPL, it measures loudness but is an average measurement of volume over a period of time. Used heavily in broadcast to provide consistent volumes from program to program and commercials, this method is becoming the standard for mixing for all platforms. Broadcasters’ specifications vary, but a target of –24 LKFS and –2 dBTP is pretty normal. We’ll discuss this more in Chapter 7 on audio post-production.

Sample Rate and Bit Depth

During a recent house- and office-moving project, I found some old cassette tapes in a box from my father. My teenage daughter had no idea what they were, or even that sound was recorded on analog tape before the advent of digital audio; and vinyl was something cool DJs did. She has only seen me record and playback to and from a computer. This process actually converts the analog sound wave into a digital signal. Converting analog audio into digital is a process where the ADC (analog to digital converter) gathers information by sampling or taking a snapshot of the sound waves in equally spaced slices. This creates points carrying frequency and amplitude information. The information between the points is drawn in to finish the wave. The higher the sample rate the more points of data to connect the sound wave, the better the sound. Anytime there is sound recorded that goes digital, there is an ADC. Converters can be standalone, in recording interfaces or mixers, and even microphones.

Keep in mind that the sample rate and bit depth of digital audio have everyth...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Table of Contents
• Preface by Jeff Greenberg
• Introduction
• Acknowledgements
• 1 Sound Basics
• 2 Storytelling with Sound
• 3 Preparing for Location Sound
• 4 Location Sound Strategies
• 5 Voiceover Narration and Story
• 6 Preparing for Your Sound Mix
• 7 Your Mix Session
• 8 What You Need to Know About Music Copyright and Licensing
• 9 Music Scores
• 10 Spatial Audio
• 11 Making Videos Accessible
• Glossary
• Resources
• Bibliography
• Filmography
• Index