Sidechain compression is a powerful technique used in contemporary music production that involves using a sidechain source, such as a kick drum, to trigger compression on a different audio track, such as a bass track. This technique is commonly used to create a "pumping" effect, where the level of the bass track is lowered whenever the kick drum hits, allowing the kick drum to cut through the mix more effectively.
The process of setting up a sidechain compression effect is relatively simple. First, the audio track that will be used as the sidechain source, such as the kick drum, is sent to a separate audio channel, called a "sidechain input." Next, a compressor is placed on the track that will be affected by the sidechain, such as the bass track. The sidechain input is then used as the "key" input for the compressor, which means that the compressor will only be triggered when the sidechain input is active.
In the case of using the kick drum as a sidechain source to trigger compression on the bass, when the kick hits, it sends a signal to the sidechain input, which then triggers the compressor on the bass track to lower the level of the bass. This creates a "pumping" effect, where the bass level drops whenever the kick hits, allowing the kick drum to cut through the mix more effectively.
Sidechain compression can also be used for other purposes as well, like vocals. Doubling vocals is one of the most common uses of sidechain compression. In this case, Waves Doubler 4 plugin is used to thicken up the vocals. The plugin can be placed on the vocal track as an insert, but he's using it as a send effect, placing it on a Return track in Live. This way, it's a very good way to enhance your vocal effect.
Sidechain compression can also be used to create more subtle effects, like ducking the background music when dialogue occurs in a film or a video game. In this scenario, the dialogue track is used as the sidechain source to trigger compression on the background music track. This allows the dialogue to be more clearly heard by reducing the level of the background music whenever the dialogue is present.
Another example is in electronic music production, the use of sidechain compression can be used to create a rhythmic effect with synths and other electronic instruments. By using a sidechain source such as a kick drum, the synth or electronic instrument can be made to pump in time with the beat. This can create a more cohesive sound, making the electronic elements feel more integrated with the drums and other instruments.
It allows you to create a "pumping" effect by using a sidechain source, such as a kick drum, to trigger compression on a different audio track, such as a bass track. It's also used to enhance vocals by using doubling effects. Sidechain compression is a versatile technique that can be used in many different ways to improve the overall sound of a mix.