Time Tracks

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A Time Track is used in conjunction with one or more audio tracks to gradually increase or decrease playback speed over the length of the audio. Speed changes are controlled by manipulating the blue "time warp" line with the Envelope Tool used for making gradual volume changes. If the blue line is dragged above the horizontal, the audio plays faster; if dragged below, it plays slower.

Time Track showing the warp line and control points

The degree of speed warping that occurs when the line is dragged to the top and bottom of the time envelope is determined by "Set Range" on the Time Track's drop-down menu.

Range dialog
Time track and audio track
Only one Time Track can be used in a project, and it affects all audio tracks on screen.

Menu

Clicking on the triangle on the Track Control Panel on the left of the track provides some options for the time track.

  • "Set Range" lets you set first the minimum and then the maximum pitch change. Values are expressed in percentage values relative to 100%.
Track panel drop-down selector

A Tutorial on Time Warping

  • You must first have at least one audio track to manipulate.
  • Choose Tracks > New Time Track
  • Change the range of time warping by clicking the Track Pop-Down Menu and choosing Set Range. The dialog will appear twice, the first time to select the lower range and the second time to select the upper range.
  • To edit the time warping, choose the Envelope Tool The envelope tool from the Tools toolbar. Before you may shape the curve you must create two points, thereafter when you drag a point the line on each side of that point moves to reflect your change. Drag points off the track to delete them.

The converter used will be the one(s) set up on the Quality Preferences tab of Preferences. You can make separate choices for Realtime (playback) and High Quality (exporting), trading speed against quality.

Older computers may be incapable of playing audio in real-time that makes use of a Time Track, however you can always Export the file as a WAV and then playback the WAV file later.

The Time Track has a ruler. As you edit the Time Track the ruler will warp to show at what time playback will reach each place in the audio.

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