Create and edit tempo changes in the Tempo Operations window

You can create tempo changes in the Tempo Operations window using the following operations:

Create Tempo Curve: Lets you create numerous tempo change events with just a few parameters, and provides a smooth overall change in tempo.
Create Constant Tempo: Creates a constant tempo in the selected area. The default setting assigns an average tempo for the selected project section (based on existing tempo change events).
Scale Existing Tempo: Alters existing tempo changes proportionally (scales them). This allows you to speed up an entire project section, without losing the relationships between any subsequent tempo changes within the area. Scaling is done by percentage.
Stretch Existing Tempo Curve: Stretches or compresses an existing tempo curve.
Thin Out Existing Tempo Changes: Reduces the number of tempo changes in the selected area.
Randomize Tempo: Adds random tempo changes based on the parameters you specify.

Create a tempo change in the Tempo Operations window

In the Tempo Operations window, choose Operation > Create Tempo Curve.
Use the Position or Time field to define the area that the tempo change should take place across: the left field sets the curve start point and the right field, the curve end point.
Enter start and end tempos in the Tempo line.
Select a curve type.
Three kinds of tempo curves are available from the Curve Type pop-up menu. Each of these offers a Curvature parameter (the field to the right of the Curve Type pop-up menu), which determines if the tempo should speed up or slow down, depending on whether positive or negative curvature values are entered.
Adjust the Curvature parameter.
Alter the concentration of graphical tempo change events with the Density parameter.
Values of 1/8 and finer should be used only if really necessary (with very slow or fast tempo changes, for example). Don’t select a resolution higher than 1/8 or finer, just to make the curve look smoother. This results in an unnecessary amount of processing, and the creation of more tempo change events than are needed.
As you change the values, the displayed tempo curve (which is calculated from the tempo settings you’ve made) is shown in red.
Note: The “Continue with new Tempo” checkbox determines whether the original tempo resumes after the tempo curve ends (unselected), or the new tempo (the last tempo change event in the curve) is maintained (selected).
Click Apply when you're done.

In the Tempo Operations window, choose Operation > Create Tempo Curve, then do one of the following:
- To remove all tempo variations between two points without changing the SMPTE time for the rightmost position: Click the Apply button.
- To retain the new tempo or return to the initial tempo: Select the “Continue with new Tempo” checkbox.

In the Tempo Operations window, choose Operation > Scale Existing Tempo Changes.
Adjust the scaling percentage using the Scale value slider.
Positive percentage values speed up sections, and negative ones slow them down.

In the Tempo Operations window, choose Operation > Stretch Existing Tempo Changes.
Define the start point for tempo changes using the Position or Time parameter.
Do one of the following:
- Enter the new end point of the tempo curve as a bar position or SMPTE value.
- Set a Stretch value for the tempo curve (as a percentage).

In the Tempo Operations window, choose Operation > Thin Out Existing Tempo Changes.
The Position or Time field defines the start and end points of the area to be processed. Density determines the number of tempo change events that remain per bar after processing. You can select values between one tempo change event per bar (1/1) and 32 per bar (1/32).

In the Tempo Operations window, choose Operation > Randomize Tempo.
Define the start and end points for tempo changes using the Position or Time parameter.
Determine the amount of deviation from the current tempo, in beats per minute (bpm) using the Randomize parameter.
Define how often the new tempo change events occur using the Density parameter. You can select values between one per bar (1/1), and 32 times per bar (1/32).