Multi-track events are significantly more powerful than simple events. In fact, before adding any sound to a multi-track event, we must turn it into a sound def, which has almost the same functionality as a simple event. With a multi-track event, we can:
Create multiple layers of sounds that play at the same time
Apply one or more DSP effects to each layer
Create custom parameters to modify the sound in real-time
Play different sounds depending on the value of a parameter
Modify any of the sound or effect properties from a parameter
Before creating a multi-track event, we must prepare a sound def for each of the sounds that we intend to use. The process is similar to creating a simple event, although the interface is a bit different. Head over to the Sound Defs section, right-click on top of any folder, and select one of the Add sound def options:

The interface used to create a sound def is a bit like a condensed version of...