Automating Audio Filter Parameters with Keyframes

You can add keyframes for any audio filter parameter, just as you can with video filter parameters. Unlike with video filter parameters, you can add keyframes to an audio filter parameter during playback as long as the Record Audio Keyframes button is selected in the Audio Mixer.

Keyframe Controls in the Filters Tab of the Viewer

To the right of each filter control is a set of keyframe controls. Like audio levels or stereo pan, filters can be keyframed to change their effect on your clip over time.

Figure. Filters tab showing keyframe controls.

For a detailed description of these controls, see Viewing and Adjusting a Filter’s Parameters.

Adjusting Audio Filter Parameter Keyframes

You can add keyframes to audio filter parameters using the Selection and Pen tools, just as you would for video filters.

To set a keyframe while playback is paused
Do one of the following:
  • Move the playhead in the keyframe graph area of the Viewer Filters tab to the time where you want to put a keyframe, then click the keyframe button for the parameter you want to set.

    Figure. Keyframe button in the Filters tab.
  • With the Option key held down, position the pointer over the keyframe graph line for a parameter. When the pointer turns into a Pen tool, click to add a keyframe to the keyframe graph line at that point.

    Figure. Pen tool positioned over the keyframe graph line for a parameter in the Filters tab.

    The keyframe appears as a small diamond on top of the keyframe graph line.

To set additional keyframes for a parameter while playback is paused
  1. Move the playhead to another point in the Filters tab’s keyframe graph area where you want to set a keyframe.

  2. Do one of the following:

    • Drag the parameter slider to set a new keyframe with that value.

    • Type a number in the appropriate field to set a new keyframe at that value.

    • Click the appropriate keyframe button to add a keyframe to the keyframe graph line of that parameter at the keyframe graph line’s current value.

    • With the Option key held down, click anywhere on a parameter’s keyframe graph line with the Pen tool to add a keyframe at that point without changing the value of the keyframe graph line at that point. You can add as many keyframes as you wish by clicking repeatedly with the Option key held down.

    The new keyframe appears as a small diamond on top of the keyframe graph line.

To record keyframes for a parameter during playback
  1. In the Viewer or Timeline, move the playhead to the area of your sequence where you want to record keyframes.

    It’s a good idea to start a few seconds before the section you’ll actually be mixing, to give yourself time to get ready.

    Note: You can only record keyframes in an audio filter parameter during playback if the Record Audio Keyframes button is selected in the Audio Mixer.

  2. Begin playback of your sequence.

  3. As your sequence plays, position the pointer over the relevant audio filter control in the Filters tab of the Viewer, and hold down the mouse button to begin adjusting that parameter.

  4. When you’ve finished making a particular adjustment, release the mouse button to insert an additional keyframe at the position of the playhead.

    The sequence continues to play.

  5. If there are any other audio filter parameters you want to adjust at this time, repeat steps 1 through 4.

  6. When you’ve finished making adjustments, stop playback.

To move the playhead in the Viewer from one keyframe to another
Do one of the following:
  • Press Option-K to move the playhead to the next keyframe to the left of the playhead.

  • Press Shift-K to move the playhead to the next keyframe to the right of the playhead.

  • Click the left or right keyframe navigation button for a parameter to move the playhead to the next keyframe to the left or right of the current position of the playhead.

To adjust the value of a single keyframe
Do one of the following:
  • Move the playhead to the keyframe you want to adjust, then adjust the appropriate parameter control to set a new value.

  • Move the playhead to the keyframe you want to adjust, type a new value in the appropriate field, and press the Return key.

  • Move the pointer over the keyframe you want to modify. When the pointer becomes a crosshair pointer, drag the keyframe up or down to change its level, or left or right to change its location.

To adjust a section of a keyframe graph line in the middle of four keyframes
  • Move the pointer over this section of the keyframe graph line. When the pointer turns into the Adjust Line Segment pointer, drag just that area up or down to modify it.

    The rest of the keyframe graph line before and after the four keyframes remains untouched.

    Figure. Section of the keyframe graph line in the middle of four keyframes being dragged.
To move a keyframe forward or backward in time
  • Move the pointer over the keyframe you want to move. When the pointer becomes a crosshair pointer, drag the keyframe forward or backward along the keyframe graph line.

    Figure. Keyframe being dragged to a new position.

    As you drag, a box displays the timecode duration of the change you’re making.

To delete a keyframe
Do one of the following:
  • Control-click the keyframe you want to delete, then choose Clear from the shortcut menu.

    Figure. Keyframe being deleted using the Clear command in the shortcut menu.
  • Move the pointer over the keyframe you want to delete. When the pointer becomes a crosshair pointer, drag the keyframe up or down out of the keyframe graph area. When the pointer turns into a small trash can, release the mouse button.

    Figure. Keyframe being dragged out of the keyframe graph area.
  • Move the playhead to the keyframe you want to delete, then click that parameter’s keyframe button to remove the keyframe.

  • Hold down the Option key and move the pointer over an existing keyframe. When the pointer changes to the Delete Point tool, click an existing keyframe with the Delete Point tool to delete that keyframe.

    Figure. Keyframe being deleted with the Delete Point tool.
To delete all keyframes
  • Click the filter’s Reset button to clear all keyframes from all parameters for that filter and restore the parameters to the default values.

    Figure. Reset button for an audio filter.