You can use audio effects to manipulate the sound in your movie. To see audio effects
settings, click Audio FX at the top of the Editing pane.
Effects list: Select an effect in this list to change the sound of audio in your movie.
Effects controls: Use the controls to change the sound of an audio clip. The controls vary
depending on the effect you selected.
Preview button: Listen to the audio clip to see how it sounds with the settings you made.
Apply button: When you like the results, click to apply the effect to the selected audio clip.
iMovie HD at a Glance