Answers.Body: <ul>
  <li><p>Add a Slider to your Null Object.</p></li>
  <li><p>Alt-click on the stopwatch next to the one of the volume controls that you want to control.</p></li>
  </ul>
  
  <p>This will open the Expressions box for the volume control, and a pick-whip icon will appear.</p>
  
  <ul>
  <li>Drag from the pick-whip to the Slider in your Null.</li>
  </ul>
  
  <p>Some code will appear in the Expressions box, something like:</p>
  
  <pre><code>temp = thisComp.layer("Null 1").effect("Slider Control")("Slider");
  [temp, temp]
  </code></pre>
  
  <p>The numbers on the volume control will turn pink to indicate that they are being controlled by an expression.</p>
  
  <ul>
  <li>Now move the slider on the null, and the volume should change on the audio track.</li>
  </ul>
  
  <p>To do this to multiple audio tracks, just follow the same process.</p>
  
  <p>Here is a screen shot to illustrate this:</p>
  
  <p><img src="https://i.sstatic.net/m1vox.png" alt="screenshot"></p>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2013-07-26T22:11:52.373Z
Answers.LastActivityDate: 2013-07-26T23:03:11.027Z
Answers.LastEditDate: 2013-07-26T23:03:11.027Z
Answers.UserDisplayName: tomh
Body: <p>Null objects don't have volume controls, but I'd like to control many audio layers in my timeline at once. </p>
  
  <p>Anyone know of a way to adjust volume or toggle mute on a bunch of layers without having to precompose them?</p>
  
Tags: <after-effects>
Title: Null object to toggle volume in After Effects?
UserDisplayName: John
ThreadText: # Null object to toggle volume in After Effects?
  
  (Asked by: username_0 on 2013-06-07)
  
  Null objects don't have volume controls, but I'd like to control many audio layers in my timeline at once.
  
  Anyone know of a way to adjust volume or toggle mute on a bunch of layers without having to precompose them?
  
  **Tags:** after-effects
  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2013-07-26. Score: 2 | Accepted answer
  
  * Add a Slider to your Null Object.
  * Alt-click on the stopwatch next to the one of the volume controls that you want to control.
  
  This will open the Expressions box for the volume control, and a pick-whip icon will appear.
  
  * Drag from the pick-whip to the Slider in your Null.
  
  Some code will appear in the Expressions box, something like:
  
  ```
  temp = thisComp.layer("Null 1").effect("Slider Control")("Slider");
  [temp, temp]
  
  ```
  
  The numbers on the volume control will turn pink to indicate that they are being controlled by an expression.
  
  * Now move the slider on the null, and the volume should change on the audio track.
  
  To do this to multiple audio tracks, just follow the same process.
  
  Here is a screen shot to illustrate this:
  
  ![screenshot](https://i.sstatic.net/m1vox.png)
  
  
  ---
  
  