How can I adjust volume in my project using Volume Envelopes?

You can raise or lower specific sections of audio in your Catalyst Edit project by using the Envelope tool.
Below the timeline in Catalyst Edit, there is a drop-down menu that displays the various available tool options. Open that menu and select Envelope Tool (or simply press V on your keyboard) to display the volume envelopes for your audio events; they will appear as horizontal yellow lines across the events. Double-click on the line to create points that allow you to manipulate the volume of specific areas, and click and drag the line to increase or decrease the volume of that area.

Anchor Points and Line Segments

You can add anchor points to the Volume Envelope line by Right Clicking and choose Add Point or just by Double Left Clicking.
When you have added points around the area that you wish to raise or lower (A), just place your mouse cursor over the line segment and Left Click and Drag up or down (B).

Right Click (A) and choose "Insert/Remove Envelope" and choose Volume.