Ducking

"Effects ducking" refers to a technique where the volume of certain audio effects (such as reverb or delay) is automatically lowered when another audio track (usually lead or vocals) is playing.

This allows the lead or vocals to be more prominent and easier to hear, while still maintaining the desired effects in the background. This technique can be used to create a more dynamic and polished sound, by preventing the effects from overwhelming the main audio elements, and making them more subtle. It makes the overall mix less muddy.

Example

Without ducking

With ducking