Time Stretch

You can time stretch an audio file or selection. When you time stretch an audio file, you change the duration (length) of the file without changing the frequency (pitch) of the file. For example, for a file containing music, the tempo of the music is changed, but not the pitch. When you time stretch an audio file, you can choose the format for time values you enter. You can select seconds, timecode, samples, frames, or a percentage.

To time stretch an audio file
  1. Select the part of the file you want to time stretch (it can be the entire file).

  2. Choose Process > Time Stretch.

    The Time Stretch dialog appears.

    Figure. Time Stretch dialog.
  3. In the Time Stretch dialog, choose the format for setting the amount to time stretch the file from the Format pop-up menu.

  4. Choose the type of algorithm to use to perform the time stretch from the Stretch Using pop-up menu.

    Any third-party time stretch algorithm plug-ins installed appear in the Stretch Using pop-up menu. The default algorithm used for time stretching is set in Soundtrack Pro Preferences. For more information, see General Preferences.

  5. In the “Length of selection” value slider, do one of the following:

    • Click the center of the value slider, then drag the slider that appears left or right to change the length.

    • Click the left arrow to shorten the length, or click the right arrow to increase the length.

    • Click the value in the value slider, then type a new value.

  6. Click OK.

For information on stretching a file graphically using the Audio Stretching tool, see Using the Audio Stretching Tool.