When you add an audio effect or background music to your movie in iMovie, you may want to make some adjustments. Luckily, iMovie provides features for editing your audio clips so that you can trim them, change the speed, and adjust the volume.
For iMovie on Mac, iPhone, and iPad, this tutorial shows you the basics of how to edit, trim, and adjust your audio clips.
Editing audio clips in iMovie on Mac
You can use actions in the menu bar as well as quick shortcuts to make adjustments to your audio clips in iMovie on Mac. This is convenient so that you can use whichever is most comfortable for you.
Trimming audio clips
If you want to trim an audio clip, you have a couple of options for how you’d like to trim it.
Trim to playhead
You can move the playhead in your movie timeline and then trim an audio clip to that exact spot. Once you move the playhead, do one of the following.
- Choose Modify > Trim to Playhead from the menu bar.
- Control-click the audio clip and select Trim to Playhead in the shortcut menu.
Keep in mind that this trims away everything on one side of the playhead, so position it carefully before you commit.
Use the clip trimmer
To work on a more precise part of the clip, you can use the clip trimmer.
1) Select the audio clip in the timeline, then choose Window > Show Clip Trimmer. You can also press Command-Backslash () to open and close the clip trimmer when a clip is selected.
2) The clip trimmer appears over the timeline, and the unused portions of the clip appear dimmed. To shorten the clip, drag the edge of the clip toward its center. To extend it, drag the edge away from its center. The section between the two edges is what stays in your movie — the dimmed material outside them is what gets left out.
If you want to keep the length of the clip the same but change which part of it plays, drag the clip from its center and then move it left or right.
3) Press Return when you finish to close the clip trimmer.
Lengthening or shortening audio clips
You can easily lengthen or shorten an audio clip in iMovie. Just skim to the beginning or end of the clip in the timeline and drag the edge of the clip — toward its center to shorten it, or away from its center to lengthen it. To extend a clip, there must be unused portions of the clip available.
You can also set the duration for the clip to an exact time. Select the clip in the timeline and click the Clip Information button (small letter "i") in the adjustments bar above the viewer. Then type the duration you want in the Duration field.
Changing the speed of an audio clip
You may want to slow down or speed up an audio clip. This is also simple to do, and you have a couple of methods; start by selecting the clip in the movie timeline.
- Click the Speed button in the adjustments bar to show the speed controls. Choose Slow or Fast from the Speed pop-up menu, then click a speed button to set the speed. To set your own value, choose Custom and type a number in the field.
- Once a speed change has been applied, a speed slider appears at the top of the clip in the timeline. Drag it right to slow the clip down or left to speed it up. This is handy for custom adjustments, because you can watch the clip’s duration change as you drag.
Playing an audio clip more slowly lowers its pitch, and playing it faster raises the pitch. If you want to keep the original pitch, select the Preserve Pitch checkbox above the viewer.
Adjusting the volume of an audio clip
If you want an audio clip’s volume to be higher or lower, you can do this in two different ways as well. Select the clip and then do one of the following.
- Drag the volume control — the horizontal line running across the audio waveform — up or down. As you drag, the level appears as a percentage value, and the waveform changes shape to reflect your adjustment.
- Click the Volume button in the adjustments bar to show the volume controls, then use the volume slider. To mute the audio clip, click the Mute button. You can also press Shift-Command-M to mute and unmute.
If waveforms don’t appear in the timeline, click the Settings button in the upper-right corner of the timeline and select the Show Waveforms checkbox. Watch the peaks as you work: yellow indicates distortion and red indicates clipping, so lower the volume until the whole waveform is green.
Fading an audio clip
Just like when creating music in GarageBand, you can edit audio clips in iMovie to fade in or out. Position the pointer over the audio portion of a clip in the timeline to reveal the fade handles, then drag a fade handle to the point in the clip where you want the fade to begin or end. Dragging the handle at the beginning of a clip creates a fade-in, and dragging the handle at the end creates a fade-out.
Editing audio clips in iMovie on iPhone and iPad
You may not have the flexibility for editing audio clips in iMovie on iPhone or iPad as you do on Mac, but you can still do the basics.
Trimming audio clips
On iPhone and iPad, trimming audio clips is basically lengthening or shortening them. (You can also use the Split feature described at the end of the tutorial.) Tap the audio clip — blue or purple — or the background music clip in green, and yellow trim handles appear. Drag the trim handles at either end of the clip to the points where you want the audio to begin and end.
If a trim handle won’t move right or left, it means there is no additional audio to work with on that end of the clip. When you’re done, tap outside the audio clip to make the trim handles disappear.
Changing the speed of an audio clip
If you want to slow down or speed up an audio clip, select it in the timeline and then follow these steps.
1) Tap the audio clip in the timeline to reveal the inspector at the bottom of the screen.
2) Tap the Speed button. A yellow bar appears on the clip, with range handles at each end.
3) In the inspector, drag the slider right to increase the speed or left to decrease it.
4) Tap anywhere outside the inspector when you’re finished.
As you drag, the relative speed is displayed below the clip — 2x means twice the normal speed, 1/2x means half the normal speed, and so on. Note that you can’t adjust the speed of a soundtrack or theme music track added from the Soundtracks menu.
Adjusting the volume of an audio clip
To turn the volume up or down, tap the clip in the timeline to reveal the inspector, tap the Audio button, and drag the volume slider left or right. To silence the clip entirely, tap the Mute button next to the volume slider; tap it again to turn the sound back on. Tap outside the inspector to close it.
Fading an audio clip
You can fade in at the start or fade out at the end of your audio clip. If you’re working with a video clip that has audio, you must first detach that audio as a separate clip before you can fade it. Select the audio clip and then do the following.
1) Tap the audio clip in the timeline to reveal the inspector at the bottom of the screen.
2) Tap the Audio button.
3) Tap Fade to reveal fade handles at the beginning and end of your clip.
4) Drag the fade handles to set the duration of the fade-in and fade-out.
Fades appear as shaded areas in the clip to show where the volume increases or decreases.
Split, background, and foreground settings
You have a few additional actions for audio clips on iPhone and iPad. Tap your audio clip in the timeline to reveal the inspector, then tap the Actions button at the bottom.
You can then choose to Split the clip, which splits it at the playhead, or move its sound to the Foreground or Background relative to the other sounds in your project. You can have three foreground audio clips and one background audio clip playing at a time, and the color of the clip changes to show which it is — green for background music, blue or purple for foreground audio. Finally, you can also Delete the clip if you no longer need it in your iMovie project.
As an alternative way to split, tap the clip so it becomes outlined in yellow, then swipe down over the playhead as if you were using your finger to slice through it.
Working with audio clips in iMovie is easy once you get the hang of the features and options on Mac, iPhone, and iPad. Have you run into any problems editing audio clips in iMovie? Let us know!
