Chapter 10. Editing Audio
How important is audio in a movie? If you ever get the chance to attend an advance test screening of a Hollywood movie, the answer may be painfully clear. I've been to screenings where the audio in some scenes consisted of just what was recorded on set—no background music, no sound mixing to balance actors' voices and dampen background noise, no re-recorded dialogue to enhance enunciation. Although quite a bit of work goes into editing audio, people tend not to notice it unless something is wrong.
I covered some methods for capturing quality audio in Chapter 5, which is the first step. But audio can be much more than just video's underappreciated sibling. In this chapter, you'll see how editing audio tracks can give depth to your movie by working independently of the video, and by adding music, narration, and sound effects.
Changing a Clip's Volume
When you import footage, the video and audio are combined in the Timeline Viewer's video track (Figure 10.1). So, as you're editing video clips, you're also editing the audio—splitting, trimming, and cropping it with the visuals. You can control how loud an individual clip plays, or change the volume level within the clip.
Figure 10.1. Although the top track is usually referred to as the video track, it also contains the clip's audio.
To set a clip's volume evenly:
To change volume within a clip:
To remove a volume marker:
Fading Audio In or Out
iMovie 2 featured controls for creating audio fades—increasing the volume from silent to full strength (fade in) or dropping the volume from full to silent (fade out). With iMovie 3's improved volume controls, you don't need the old Fade In and Fade Out checkboxes, but sometimes you still want the effect. Here's how to do it.
To fade audio completely in or out:
To change the fade duration: