328 The Digital Filmmaking Handbook, 4E

Audio Editing Hardware

Sound editing applications are powerful tools, but even though you can get away with performing all of your audio edits using software alone, you might want special hardware to augment the process.

nMixing Boards. If you’re more comfortable with sliders and knobs than with a mouse, then you might want a mixing board for mixing and balancing your tracks. Although you might have used a simple mic mixer or four-track mixing board during your shoot, you’ll probably want a beefier mixing board for your postproduction editing. FireWire-based mixing boards are the easiest to hook up because they don’t require additional hardware.

nMicrophones. Obviously, if you end up needing to re-record dialogue, or to record sound effects on location, you’ll need microphones. For voice-overs and other dialogue recording, your best option will be a good handheld mic. Whether you choose to record directly into your computer or record into a tape deck, be sure you have the necessary cables and connectors to hook up your mic.

nSpeakers. It almost goes without saying that all sound editing workstations need a good pair of speakers. See the section on audio hardware in Chapter 11 for more on speakers and other audio-related hardware.

nAudio PCI Cards. Many dedicated sound editing apps can be paired with special PCI cards designed to process audio in your computer. In addition, they add connectivity to other audio hardware devices. Check your software manufacturer for details.

Editing Sound

Once your equipment is in place, it’s time to start working your way through the list of sound design elements that you created during your spotting session. In addition to the obvious sound effects—gunshots, screams, footsteps, howling wind, and so forth—and the questions of mood, atmosphere, and drama that we discussed earlier, there are a number of other sound edits that might be on your list. The following are all things you should look for when spotting and editing.

Unintelligible Dialogue

Remember that you already know what your actors are saying. Whether you wrote, directed, or edited (or did all three jobs), you’ve probably heard each line hundreds of times. Consequently, you might be more forgiving of a mumbled or quiet line of dialogue. Pay close attention to your character’s speech, and make sure that it is clear and intelligible. If it’s not, consider using EQ (more on this later), boosting the level, or using a different take (audio, or both audio and video). (Sometimes, you can sneak in a word from another take without any visible loss of sync, but be careful if you’re going to end up projecting on a big screen.) As a last resort, you can always bring the actor in to re-record or “loop” his or her dialogue (more on ADR later in this chapter).

Changes in Tone

Does the overall audio quality change from one edit to another? Changes in tone can result from changes in microphone placement, changes in location, changes in ambient sound, or just weird “acts of God” that you might not be able to explain. Hopefully, you recorded some room tone at your locations.

A change in tone can often be masked by fading from one audio source to the next, to mask the change in sound quality. A bed of room tone, ambient sound, or music can further conceal this “edit” (see Figure 15.8).

Figure 15.8

To improve sounds with mismatched tone, you can apply a bed of room tone. A cross-dissolve between the two bad tracks might further improve things.

Is There Extraneous Noise in the Shot?

When shooting on location, it can often be difficult to keep a quiet, controlled set. If there are extra, distracting noises—a loud conversation or music playing, for example—see if you can mask these sounds by placing sound or music effects that will keep your audience focused on your action.

Remember: The audience will pay attention to the things you lead them to. Just as you can brighten the foreground of your video to draw attention to your subject, you can “brighten” the foreground of your audio to ensure that your audience listens in the right “direction.”

330 The Digital Filmmaking Handbook, 4E

Are There Bad Video Edits That Can Be Reinforced with Audio?

Sometimes, a video edit with weak motivation can be reinforced with a good strong sound. The easiest way to reinforce an edit is to place a beat of music at that location. The rhythm of your music track will carry through to the audience’s visual sense. If you’re using prerecorded, or “canned,” music, consider adjusting the start of the music so that a strong beat falls on your weak edit. If you’re working with an original score, perhaps your composer can suggest a change in music.

In addition to music, weak edits can be reinforced with an off-camera sound effect. A breaking window, for example, will provide plenty of motivation for a cut to another shot.

Is There Bad Audio?

There are many technical problems that can corrupt audio, from a boom operator bumping the mic, to a short in a cable, to interference with electrical fields. To eliminate thumps and bumps on the microphone, you can usually just bring the level of the audio down or cut it out. Hopefully, there’s no dialogue or other important sounds during those moments. If there are, you might need to re-record those audio elements or try to do so. As we’ll see later, other troubles can be corrected through EQ adjustments.

The clicks and pops that can result from a short in a cable are usually easy to fix because they’re brief. Even if a click falls over dialogue, removing it usually won’t affect the quality of your recording. Even if a click is in the middle of a word, sometimes just cutting it out sounds better than leaving it as is. Remember that, as with bumps, when you remove a click or pop, you don’t want to delete it or use a “close gap” command, as this will shorten your sound and throw your sound and video out of sync. Instead, use a “lift” command, or select the area and use a silence command to reduce the selected area to nothing, or copy an appropriate length of room tone into the selected area.

If you have a hum in your audio, then your life might have just gotten very complicated. Some hums are easy to fix and can be removed with a simple notch filter. Fluorescent lights and some electrical sources sometimes create a 60Hz hum in your audio. Setting a notch filter to remove all the sounds at 60Hz can frequently eliminate or reduce a hum. Note that hums sometimes produce additional harmonic hums that also need to be removed. You can remove these with separate notch filters or use a special hum remover that automatically notches harmonics.

Some hums might be too “dirty” (that is, they fall over too much of the audio spectrum) to be removed. In most cases, living with it or re-recording your sound track is your only option.

If your hum is slight, you can often reduce or eliminate it with a simple EQ filter.

Are There Vocal Problems You Need to Correct?

While flubbed lines can often be fixed by re-recording, or pulling audio from alternate takes, other vocal problems might require special filtering. For example, if an actor’s dialogue has loud, shushing “s” sounds, you can often correct these with a de-essing filter or with an EQ adjustment.