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Audacity: Volume Adjustments - Keyframing for Ducking and Fading

Audacity, Version: 2.3.2. Be aware that different versions of Audacity will vary in appearance and functionality. Full Guide: View/Download

Audio ducking refers to the practice of lowering the volume of a background music track while people are speaking, to ensure the dialogue can be heard. Ducking in Audacity is achieved through a process called keyframing. A keyframe is like a snapshot of the volume at a single moment; when multiple keyframes are at different volume levels, Audacity automatically transitions the volume between them. Keyframing is done with the Envelope Tool.

To duck audio with keyframing:
  1. Select the Envelope Tool; bluish-purple lines will appear on the top and bottom of tracks in the Timeline.
  2. Click on the track to create four keyframes for each section to be ducked. Each keyframe looks like four vertically-stacked white dots.
    • Keyframe 1: start of the fade-out
    • Keyframe 2: low background volume (during dialogue)
    • Keyframe 3: start of the fade-in
    • Keyframe 4: back to full volume

  3. Click-and-drag the white dots on the keyframes to reposition. The waveform height will adjust accordingly. 
    • Move keyframes vertically to decrease/increase volume.
    • Move keyframes horizontally to change timing. Keyframes close together will be a quick change in volume; keyframes further apart will be a slow change.
To delete a keyframe, click-and-drag it outside of the track; upon the release of the computer mouse the keyframe will disappear.

Fade In/Out

Fades in/out can be created using keyframes (explained in the above section) as well as with the Fade In/Out Effects. The Fade In/Out Effects are not recommended as these actions are impossible to undo later on.

To fade with keyframes:
  1. Create two keyframes.
  2. Click-and-drag one of the keyframes inwards to decrease its volume.
    • Fade-in: adjust the first keyframe
    • Fade-out: adjust the second keyframe

To fade with Fade In/Out Effects:
  1. With the Selection Tool, click-and-drag to highlight the desired section to be faded in/out.
  2. Navigate to Effect > Fade In/Out.

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Keywords:Audacity, workshop, software, production, guide, editing, audio, volume, ducking, keyframing   Doc ID:86090
Owner:Misty B.Group:Pacific Lutheran University
Created:2018-09-27 12:13 PDTUpdated:2021-04-19 11:15 PDT
Sites:Pacific Lutheran University
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