Sidechain Compression

Lore & Background

In the context of Avicii's music, sidechain compression was a key technical tool for achieving his signature sound. The source material describes how compression is used in music production to make instruments 'sit' more nicely in the mix, ensuring they 'neither disappear during short periods of time, nor overpower the other instruments.' Sidechain compression applies this principle by using a specific instrument, like a kick drum, to trigger the compression on other elements, such as basslines or synth pads. This creates a deliberate, rhythmic 'pumping' effect where the bass ducks out of the way with each kick hit. This technique is not unique to Avicii but is a standard practice in electronic music production, particularly in genres like progressive house, to maintain a clean and powerful low end. The source notes that compression can 'increase average output gain' and 'add clarity under noisy circumstances,' which aligns with the goal of making a kick drum and bassline work together without muddying the mix.

In Their Own Story

The source material does not provide any specific narrative or anecdote about Avicii using sidechain compression in a studio setting. It only describes the general technical process and its common uses in music production.

Reader's Guide

To implement sidechain compression as Avicii might have, a producer would use a compressor with a side-chain input. The process begins by inserting a compressor on the track to be affected, such as a bassline or pad. The kick drum track is then routed to the compressor's side-chain input. The compressor's threshold is set so that the kick drum's signal triggers gain reduction. The ratio determines how much the bass level is reduced; a higher ratio (e.g., 4:1 or higher) creates a more pronounced ducking effect. The attack time controls how quickly the compression engages after the kick hits, while the release time determines how quickly the bass returns to its original level. A fast attack ensures the bass ducks immediately, while a slower release creates a longer, more gradual 'pump.' The source explains that 'attack is the period when the compressor is decreasing gain' and 'release is the period when the compressor is increasing gain.' By adjusting these parameters, a producer can fine-tune the rhythmic feel, making the track 'breathe' in time with the kick drum. This technique is a direct application of the downward compression described in the source, where 'loud sounds above a certain threshold' are reduced.

Did You Know?

• Sidechain compression is a form of downward compression, which reduces the volume of loud sounds above a threshold.
• The technique uses a 'side-chain' where the signal level of one audio source (e.g., a kick drum) is measured to control the gain reduction applied to another signal.
• A compressor with a high ratio (e.g., ∞:1) and short attack time is effectively a limiter, which can be used for extreme sidechain effects.
• The attack and release settings on a compressor determine how quickly the gain is reduced and restored, shaping the rhythmic 'pumping' character of the effect.
• Compression is used in music production to make instruments more consistent in dynamic range so they 'sit' better in a mix.