| Ducking is when you want one sound (recorded track) to trigger the compressor that is on another track. Her is an example...
Let’s say you are mixing audio for a football game on TV. In your mixer, you may have the audio from the crowd cheering. On another track, the announcer’s voice. The producer tells you he wants the cheering to always be loud because it helps to excite the Television audience. But when the announcer talks, you can hardly hear him. You don't want to sit there and turn the “crowd” track up and down all day so, enter the ducking technique. You want the compressor to turn down the crowd track when the announcer talks, and then back up when not talking. So the compressor must be "triggered" by the announcer track.
You run the crowd track through the compressor as normal so it can get compressed (turned down) when needed. You run the signal from the announcer’s voice into the sidechain input. You then set the sensitivity so that when the announcer is not talking, the compressor will do nothing. When the announcer is talking, the compressor will be triggered and turn down the crowd noise. If you set the attack and release times short enough, then not many people will even notice that it is occurring.
In studios we use this trick with kick drum and bass. Or perhaps with vocals and a loud instrument. |