In this article
Sidechain compression uses a detector signal to control gain reduction. An external source, such as a kick, can make another part dip briefly. The result depends on routing, detector settings and the compressor’s timing.
1–2. Confirm the trigger and choose the goal
Route the intended source to the compressor’s external sidechain and verify that gain reduction follows it. Decide whether you want subtle separation or obvious pumping. Those goals require different amounts and timing; a large dip is not automatically a clearer mix.
3. Make space between kick and bass
Place the compressor on the bass and trigger it from the kick. Adjust the reduction so the kick is audible without unnecessarily removing the bass’s body. Compare with shorter bass notes or a different kick sound, which may solve the same problem more simply.
4. Shape the recovery with release
The bass or pad needs to return at a useful moment in the groove. A release that is too long can leave the part suppressed; one that is too short may create distracting modulation. Use tempo as context, then choose the timing by listening.
5. Duck effects around a lead
A vocal or lead can trigger compression on its reverb or delay return. The wet sound dips during the phrase and becomes more audible in the gaps. Check that breaths or noise do not trigger unwanted movement and that the tail returns smoothly.
6–7. Focus the detector or the affected range
A sidechain filter changes what the detector responds to; it does not necessarily restrict which output frequencies are reduced. For frequency-selective ducking, use a processor that supports dynamic bands or multiband control. Confirm the behavior in its documentation and listen to the complete signal.
Try this in your project
Set up kick-triggered bass ducking. Compare a short, medium and long release at the same reduction amount. Then reduce the amount until the effect does its job without drawing attention, unless pumping is the intended sound.
Quick reference
| Focus | What to try | What to listen for |
|---|---|---|
| Routing | Verify which signal triggers reduction | Predictable movement |
| Timing | Match recovery to the phrase | The part returning when needed |
| Frequency | Distinguish detector filtering from band processing | The intended range actually changes |
Write the parts before mixing them
Captain Plugins helps you write chords, melody, bass and drum parts. Balance and process those parts with the mixing tools in your DAW; composition tools do not replace a mix or mastering workflow.
Captain Plugins 8 overview
See the update video for the current canvas and editing workflow.
Common questions
Does filtering the sidechain EQ only that range of the bass?
Not in an ordinary broadband compressor. The filter affects detection, while gain reduction can still affect the whole signal.
Should the kick always trigger every instrument?
No. Choose the parts that need space or the rhythmic effect. Unnecessary ducking can weaken the arrangement.