Watch a movie with the sound turned off. Conversations without dialogue become unintelligible, fight scenes without grunts and groans lack punch, explosions without sound effects look weak, and romantic montages without music look silly. You get the picture.
Welcome to the magical world of sound — and its powerful ability to add meaning, emotion, and dimension to the world of storytelling. In this article, I show you some tips and tricks for capturing a great recording and enhancing your project's audio during the post-production stage.
In my experience as an audio recording engineer and instructor, I've learned that many of my students and colleagues expect quality sound to originate from complex solutions, while in fact it's often the simplest techniques that can make the biggest difference.
The following sections concern the most important part of any shoot when you want good audio — the microphone. Learn what kind to get, where to place it, and how many to use.
Always set up some kind of external microphone ("mike"). External shotgun and lavalier microphones (see Figure 1) exhibit a better frequency response and greater flexibility than on-board camera mikes.
What does this mean? There are many different tones or frequencies to the human voice, from deeper, bass tones to midrange tones and up to higher, treble tones. I've found that external shotgun mikes and lavalier mikes do a better job of picking up these varying tones and add a richness to the recording that on-board camera mikes never seem to capture.
Aside from reduced sensitivity, on-board camera mikes also tend to add more electronic noise to the recording and limit the ability to get a more directional sound.
Tip: If you ever find yourself in a situation where the camera mike is the only one on hand, consider your smartphone as a means to capture a good recording. This can work wonders simply because it can be placed closer to the sound source than the camera. As a standalone device without cords or stands, a smartphone also enables you to be more creative as you place it on the set.
Place the microphone closer to the sound source. Don't limit your recording source to the camera's location. This is beneficial for perspective and proximity, and enables the camera to move freely without affecting the audio.
By placing a microphone closer to the sound source, you can get a more intimate sound as opposed to an indirect sound that inherently contains more room reflections and environmental intrusions.
A lavalier microphone picks up very direct, intimate sound simply by the nature of it being extremely close to the voice. For close-up shots, this works best because the perspective of the camera and the intimate sound of the voice match perfectly.
For instance, in a scene where all you see is a close shot of a character and not much of the space, a shotgun mike will pick up more of the room than you actually see, causing a mismatch between what you hear and see. When the camera angle changes from a medium to a wide shot, I usually reach for a shotgun mike. This allows me to finesse the mike position and insert more environmental nuances into the recording.
More often than not, the environment in which you record contains a certain amount of noise. This could be anything from traffic, heating and cooling noise, low-frequency rumble, cell phone interference, or a plethora of other invading hums and signals. Therefore, getting close to the sound source yields a greater ratio of signal to noise. In extremely noisy scenarios, this is another reason why a lavalier mike can work better than a shotgun mike.
When shooting in a studio environment or an office, it's extremely important to turn off cell phones to eliminate interference, and if possible, turn off any fluorescent lights or refrigerators that are in the space.
Another invaluable technique is to capture one minute or so of ambient sound or room tone in each environment (especially noisier spaces). This will come in handy during dialogue editing and noise reduction. These sources of room tone in each environment can replace bad sections of audio and can also be used as a source of noise to load into the noise-reduction tool. Sample noise is important to have because the noise-reduction tool needs a source of noise without dialogue to be able to analyze the noise and eliminate it from the dialogue.
If the recording situation permits, I always encourage people to use both a shotgun mike and a lavalier mike. If your camera or recording device has two microphone inputs, set up both microphones and capture each signal independently. You will thank yourself later in post-production. Recording two mikes separately provides greater flexibility in the editing stage — with regard to matching the camera perspective — and gives you a backup audio signal in case one of the microphones becomes problematic during recording.
The following sections cover the ways you can fine-tune your audio after the shoot using specific tools and settings in Adobe Premiere Pro CC and Adobe Audition CC.
After having captured some great audio, it's time to dial in frequencies and dynamics. One of the best tonal enhancement tools is the equalizer (EQ). The EQ in Adobe Premiere Pro CC works great for most recordings. It can tonally optimize your audio by allowing you to balance lower bass tones, midrange tones, and higher, treble tones. The EQ can also be used to eliminate low-frequency hum or smooth out high-frequency hiss. In Figure 2, I reduce low frequencies with the left dial and add a slight presence peak for the voice with the 4000 Hz. frequency dial. I've found the presets to be right on target for what I need. Just apply the EQ to a clip or track and select the appropriate preset.
After audio frequencies are cleaned and tonally optimized, it's time to even out those erratic loudness levels. The compressor is the perfect tool for this job. By its very nature, a compressor is a tool that evens out loudness levels; it optimizes the audio by bringing loud passages down a little and low-level passages up. The result is an averaged level of loudness consistent throughout the length of the program material. This prevents the audience from having to constantly adjust the volume controls.
Start with the compressor in Adobe Premiere Pro and apply it to a track as opposed to a clip. Then you can dial in the parameters starting with one of the effect presets. Figure 3 shows the compressor in action on a voice track. With the threshold set at –18 dB, any loud sound that rises over this point will be compressed and brought down in level to better match the average level of the voice.
After completing the tonal and dynamic enhancements, it's time to establish a good balance between all of the sound elements. This is referred to as the art of mixing.
Here's one cool trick I've discovered:
This is a classic trick of mixing other elements around the voice. In the end, if your viewers cannot hear the words because of other sound elements, they will not follow your story, and their ears will drift.
In a world of constantly changing technologies, it's very important to monitor or listen to your mix on several different playback systems. Headphones are a great way to check how the sound is translating to smaller, compact speakers. For accurate headphone monitoring, I like to use Sony MDR-7506 headphones (see Figure 4) because they provide a great representation of the audio throughout the entire audible spectrum. Cheaper headphones like iPod ear-buds can work, but I would avoid making any major sound-mixing decisions with them because they typically don't reproduce the entire audible spectrum. Reference monitor speakers are the most accurate way to check how the sound will translate in a theater or larger playback systems. Even laptop speakers can be useful in making sure that your mix will translate on smaller computer systems.
Even in great recordings, undesirable noises creep in. Subtle movements around a mike, or mouth movements that make undesirable noises (such as clicks), are often referred to as transients. These can become extremely distracting.
Here's where you take your audio clip into Adobe Audition CC and use the Click/Pop Eliminator tool. This tool analyzes your sound's waveform and looks for clicks that should be removed before making a final output. I love that it's called the Eliminator because that's exactly what it does — it redraws the waveform, completely eliminating undesirable transients:
Figure 6 represents a distracting voice artifact and the cleaned-up portion of audio. This tool is extremely intuitive and easy to use, and the results are amazing.
Sometimes during the recording process, you cannot eliminate unwanted noises. The shoot must go on. In these scenarios, there can be an invading low-frequency noise, like a rumble or more commonly a hum, stretching across multiple frequencies. Other invading noises can come from sirens, cell phones, and airplanes.
Do your best to address this on set, but for those noises outside your control, reach for the noise reduction tools in Adobe Audition. These will analyze the recording by areas of tones. For example, Audition can actually identify low-frequency hum or high-frequency hiss and separate this noise from the desirable information within the recording. It's unbelievable.
Examine Figure 7 to see what I mean. The audio waveform is in the top section; the spectral display below it represents a visual spectrum of the audio information using colors. In that lower section, you can see the plane flying overhead represented as a red horizontal line. With the paintbrush selection tool, the spectral display enables you to paint out and completely eliminate this obtrusive noise.
Once you've painted out a short section of an obtrusive noise, use the Learn Sound Model function (see Figure 8) to load this pattern into its search engine so it can find the same recurring noise throughout your audio clip and remove it for you. It's amazing. Finally, use the Noise Reduction effect (see Figure 9), which is a heavy-duty noise removal tool.
Don't overcomplicate your audio production process. Keep it simple and trust your ears. As you become more familiar working with external microphones, on-set scenarios, and intuitive audio enhancement tools, your creativity will flourish.
Check out Adobe TV for the latest features and techniques in Adobe Premiere Pro and Audition. Here are a few great videos to get you going:
If you want to delve deeper into the fundamentals of dialogue editing, I recommend reading John Purcell's book, Dialogue editing for motion pictures: A guide to the invisible art.
Ryan Kleeman is an audio recording engineer, sound designer, and instructor based in San Francisco. Teaching audio production courses at BAVC and The Art Institute, Ryan has trained industry professionals for a variety of media outlets. His work for Studio Guapo and Overlap Studios includes music production and post-production audio for independent films and commercial productions.