The Envelope tool lets you specify the volume at specific points within an audio track in VEGAS Pro, Movie Studio Platinum, ACID Pro and CD Architect.
The following guide explains how.

• To adjust the volume within a specific track, you want to first create a volume envelope by selecting the Envelope Edit Tool from the Transport and Editing toolbar or by going to "Edit" > "Editing Tool" > "Envelope".
• Right-click the audio track you want to edit and select "Insert/Remove Envelope" > "Volume". You should now see a blue line running through the audio track.
  

• Double-click the blue line to create an envelope point.
• You can adjust the volume by dragging individual envelope points or entire line segments up and down.

Note: If you don't see the envelope, make sure the option "Show Envelopes" is enabled under "View".