Audio on the timeline
The audio levels and stereo or surround positioning of individual clips can be adjusted directly on the project timeline using audio keyframing. The same operations can also be accomplished with the Audio Mixer panel, which pops out to the right of the timeline header when you click its access button. Both methods have their own advantages. Making the adjustments on the timeline gives a good sense of time versus volume or balance, whereas the Audio Mixer, in combination with the Panner, facilitates mixing – separately adjusting the volume and balance of each audio-containing track.
The Panner tool is fully surround-capable. For maximum flexibility, you can position any clip’s audio as desired in a two-dimensional listening field – from front to rear as well as left to right.
If you mix the audio for every clip as though for surround playback, you can still output a movie file with a stereo soundtrack using just the left-right balance information. If you further decide to output your project on DVD, the 5.1 surround-sound production will already be complete.