By automating mixes, you can change mix settings over time. For example, you can automatically increase volume during a critical musical passage and later reduce the volume in a gradual fade out. See this video tutorial to watch mix automation in action.

Automation envelopes visually indicate settings at specific points in time, and you can edit them by dragging keyframes on envelope lines. Envelopes are nondestructive, so they don’t change audio files in any way. If you open a file in the Waveform Editor, for example, you don’t hear the effect of any envelopes applied in the Multitrack Editor.

With clip envelopes, you can automate clip volume, pan, and effect settings.

On stereo tracks, clip volume and pan envelopes appear by default; you can identify them by color and initial position. Volume envelopes are yellow lines initially placed across the upper half of clips. Pan envelopes are blue lines initially placed in the center. (With pan envelopes, the top of a clip represents full left, while the bottom represents full right.)

Show or hide clip envelopes

Clip envelopes are visible by default, but if they interfere with editing or are visually distracting, you can hide them.

Show or hide individual automation parameters

Disable clip keyframe editing

To avoid inadvertently creating or moving keyframes, disable keyframe editing.

Automating track settings

With track envelopes, you can change volume, pan, and effect settings over time. Adobe Audition displays track envelopes in an automation lane below each track. Each automated parameter has its own envelope, which you edit just like clip envelopes.

Create track envelopes

Track envelopes let you precisely change track settings at specific points in time.

Record track automation

While playing a session, you can record adjustments you make to track volume, pan, and effect settings, creating a mix that dynamically evolves over time. Adobe Audition automatically converts your adjustments into track envelopes, which you can edit with precision.

1. In the Main panel, position the current-time indicator where you want to start recording automation.
2. Choose an option from the Track Automation Mode menu.
3. To start recording automation, start playback. As audio plays, adjust track or effect settings in the Editor, Mixer, or Effects Rack panels.
4. To stop recording automation, stop playback.
   

Track Automation Mode options

In the Editor panel or Mixer, you can choose one of the following modes for each track:

Ignores track envelopes during playback and mixdown, but continues to display envelopes so you can manually add or adjust keyframes.

Applies track envelopes during playback and mixdown, but doesn’t record any changes you make to them. (You can preview such changes, but keyframes return to recorded settings.)

When playback starts, overwrites existing keyframes with current settings. Continues to record new settings until playback stops.

Begins recording keyframes when you first adjust a setting, and continues to record new settings until playback stops.

Similar to Latch, but gradually returns settings to previously recorded values when you stop adjusting them. Use Touch to overwrite specific sections of automation while leaving others intact.

Protect settings when recording automation

When recording automation, you may want to protect certain parameters from inadvertent changes, while adjusting other parameters.

1. At the left of the Editor panel, navigate to the specific track's controls.
   
2. Click the Show/Hide Automation Lanes icon [ICON].
3. From the Show Envelopes menu, choose the parameter.
4. Click the Protect The Parameter icon [ICON].
   

Optimize recorded automation keyframes

To prevent recorded automation from creating excessive or irregular keyframes, optimize the following settings in Multitrack section of the Preferences dialog box.

Determines how fast parameters return to original values in the Touch mode. You can set values from 0.00 to 5.00 seconds; the default value is 1.00 second.

Removes any keyframes that represent static, unchanging parameter settings.

Creates keyframes at time intervals larger than the specified value. Enter an interval between 1 and 2000 milliseconds in the Minimum Time field.

Adjust automation with keyframes

Keyframes on envelope lines change clip and track parameters over time. Adobe Audition automatically calculates, or interpolates, all the intermediate values between keyframes using one of two transition methods:

• Hold  transitions create an abrupt change in value at each new keyframe.

• Linear  transitions create a gradual, even change between keyframes.

You can also apply spline curves to an entire envelope, overriding the keyframe-specific setting above to create natural-sounding transitions that change in speed near keyframes. (See About spline curves for graphs.)

Add a keyframe

Do either of the following:

• Position the pointer over an envelope line. When a plus sign  appears, click.

• Position the playhead where you’d like a track parameter to change. Then click the Add Keyframe icon  in the track controls.

Navigate between track keyframes

Select multiple keyframes for a parameter

• Right-click any keyframe, and choose Select All Keyframes.

• Hold down Ctrl (Windows) or Command (Mac OS), and click specific keyframes.

• Hold down Shift, and click to select a series of keyframes.

Reposition keyframes or the envelope line

• To reposition selected keyframes, drag them. (To maintain time position or parameter value, hold down Shift and drag.)

• To reposition a segment of an envelope without creating a keyframe, hold down Ctrl (Windows) or Command (Mac OS), and drag.

Change the transition between two keyframes

• Right-click the first keyframe, and select Hold Keyframe to abruptly change values, or deselect it to gradually transition from one value to the next.

Apply spline curves to an entire envelope

• Right‑click an envelope line, and choose Spline Curves.

Delete keyframes

• Right-click an envelope line, and choose Delete Selected Keyframes. Or, drag an individual keyframe off a clip or track.

Disable clip keyframe editing

To avoid inadvertently creating or moving keyframes, disable keyframe editing.

• From the Multitrack menu, deselect Enable Clip Keyframe Editing.

Edit keyframe manually

Right-click on a keyframe to open the context menu on a track automation envelope or a clip automation envelope in a Multitrack Session, and choose Edit Keyframe. A dialogue box will appear. Enter in a time value and a parameter value for the particular keyframe. For parameters which are not number-based such as on/off switches, there will be a tooltip on the second control in the dialog which shows the name for the parameter value.