More Sound Advice

Waveform Tips

When you've used the View menu to display audio waveforms, iMovie HD's timeline snapping feature snaps the playhead to silent portions of clips (specifically, when you scroll to within three frames of silence).

To work with more precision when viewing waveforms, zoom in on the timeline. If the audio in a track is on the quiet side, the waveform may be hard to see. Solution: select the audio clip and press the up-arrow key. This accentuates the spikes in the waveform. To make the spikes smaller, press the down-arrow key.

When you import an audio clip or music track, iMovie HD must render the track's waveforma red progress bar appears at the bottom of the audio track, and the waveform appears a bit blurry until iMovie HD renders it. Because this process takes some time, you may want to leave the waveform display turned off unless you need it for precise editing or volume adjustments.

Trimming Audio

You can trim the start and end of an audio clip using the same direct-trimming techniques described on page 232. As with video clips, you can reclaim audio that's outside of a clip's boundaries by resizing the clip.

Scrubbing Audio

Here's a handy way to locate the exact spot to trim or split an audio clip. Zoom in on the timeline, then press the Option key while slowly dragging the iMovie HD playhead. Your audio plays back, but is slowed down. The sound even plays backwards when you drag the playhead to the left. (Beatles fans: import some White Album songs from your iTunes library and have fun.)

Extracting Audio

At times, you may want to use only the audio portion of a clip. For example, you're making a documentary about your grandmother's childhood and you'd like to show old photographs as she talks.

To do this, drag the video clip to the timeline, then select the clip and choose Extract Audio (1-J) from the Advanced menu. iMovie HD copies the audio, places it in Audio Track 1, and mutes the audio in the video clip.

Next, select the video clip in the timeline and press the Delete key. The video vanishes but its audio lingers on, and you can now position still images and other clips in the video's place. You can also drag the audio elsewhere in the timeline.

Overlapping Audio in the Timeline

iMovie HD may provide just two audio tracks, but that doesn't mean you're limited to two simultaneous sounds. You can overlap multiple audio clips in the timeline's audio tracks: simply drag one audio clip on top of another.

Repeating Sound Effects

You might want some sound effects to play for a long period of time. For example, iMovie HD's Hard Rain sound effect is less than 10 seconds long, but maybe you need 30 seconds of rain sounds for a particular movie.

For cases like these, simply repeat the sound effect by dragging it from the Audio pane to the timeline as many times as needed. You can also duplicate a sound by Option-dragging it in the timeline. If the sound effect fades out (as Hard Rain does), overlap each copy to hide the fade.

You can build magnificently rich sound effect tracks by overlapping sounds. To create a thunderstorm, for example, drag the Thunder sound effect so that it overlaps Hard Rain. Add the Cold Wind sound while you're at it. And don't forget to use iMovie HD's audio controls to fine-tune the relative levels of each effect.

Get links to sources of sound effects and music. www.macilife.com/imovie

Camcorder Sound Settings

Most miniDV camcorders provide two sound-recording settings: 12-bit and 16-bit. Always record using the 16-bit setting. If your sound and picture synchronization drift over the course of a long movie, it's probably because you recorded using 12-bit audio.

Muting an Audio Track

You can mute an audio track entirely by unchecking the box to its right in the timeline viewer. If you uncheck the box next to the video track, iMovie HD mutes the video's sound. This can be handy when you're replacing the audio in a series of clips with an audio beda segment of background audio that will play across multiple clips.

Splitting Audio Clips

You can divide an audio clip into two or more separate clips whose position and volume you can adjust independently. First, select the audio clip you want to split. Next, position the playhead where you want to split the clip. Finally, choose Split Selected Audio Clip at Playhead from the Edit menu or press -T.

Sources for Sound Effects and Music

Sound Effects

iMovie HD's library of built-in sound effects, accessed through the audio section of the Media pane, covers a lot of aural ground.

But there's always room for more sound, and the Internet is a rich repository of it. One of your first stops should be FindSounds, a Web search engine that lets you locate and download free sound effects by typing keywords, such as chickadee. SoundHunter is another impressive source of free sound effects and provides links to even more audio-related sites.

Most online sound effects are stored as WAV or AIFF files, two common sound formats. To import a WAV or AIFF file, use the File menu's Import command or simply drag the file directly to the desired location in the timeline viewer.

Managing Sound Effects

If you assemble a large library of sound effects, you might find yourself needing a program to help you keep track of them. You already have such a program: it's called iTunes. Simply drag your sound effects files into the iTunes window. Use the Get Info command to assign descriptive tags to them, and you can use iTunes' Search box to locate effects in a flash. You might even want to create a separate iTunes music library to store your sound effects.

Music Sources

You'll find a symphony's worth of music on the Internet. For private, non-commercial projects, try Freeplay Music (www.freeplaymusic.com). You can download and use its music clips for, yes, free. For commercial projects, however, be sure to carefully read the company's rate card and licensing requirements.

Plenty of music is also available from sites such as SoundDogs, KillerSound, and Award Winning Music. These sites have powerful search features that let you locate music based on keywords, such as acoustic or jazz.

Loopasonic is another cool music site. It offers hundreds of music loopsrepeating riffsthat you can assemble into unique music tracks and use in GarageBand (which, of course, you can use to compose your own movie music).

And for building custom-length music tracks, you can't beat SmartSound's Movie Maestro software. Movie Maestro provides an expandable library of songs, each of which is divided into blocks that the Music Maestro software can assemble to an exact length.