What about the sound of ice cubes tinkling around a chilled glass? That summertime cannonball splash from a kid jumping into a pool? Tires sliding across wet pavement on a dark, empty road? These sound descriptions are clear and distinct, and create a great mental visual for the reader, but did you notice something else? Each sound incorporated a seemingly meaningless but actually important secondary sensory cue. The sound of ice cubes doesn't change much if the glass is chilled or not, but that added sense of touch solidifies our understanding of the sound. Now we can see the frost on the glass or the condensation dripping down the side, even when the attention is on the sound. Does a jump in the pool sound different in summer? Do tires skid louder at night? No - but the sound stands out more.
Let's use that jump-into-the-pool one some more, and start exploring. It can be a splash if we want, or it can be that great ker-plunk sound of the kid cannonballing into the water, followed by the water clapping together behind the child. If I describe that splash with a little bit of variation in the action, the sound changes. Depending on how we close the sentence, the start of the sentences changes shape. Listen to all these different sounds that happen even though all the sentences start the same:
"I heard a splash in the water, like...
- ...a diver piercing through the surface."
- ...a bowling ball dropped in a fish tank."
- ...a mob informant's bound body hitting the Chicago River."
Each sentence starts the reader from the same place, then a simile changes the scene and brings other concepts into the image, all while engaging the reader. It's just a sound, right? Not anymore. The senses blend with the imagination, and your description gains a new dimension. It takes on a new quality. It gains life.
Look back at that dodge ball. My guess - you're thinking about its sound again. That's what vivid description does.