A sidechain compression configuration can be useful to create a ducking or pumping effect on particular audio source. The effect is usually triggered by a transient heavy track (eg. a bass drum track). This article will explain how to create such an effect in Pro Tools using the Native Instruments VC 76 compressor on a pad.
- In Pro Tools there are two audio tracks: The first track (named Pad) contains a sustained pad sound. The second track (named BD) contains bass drum hits playing each quarter note of a bar.
- On the Pad track load VC 76-AAX (stereo) as an effect plug-in.
- Activate the Sidechain button (below the SC Gain knob) on the plug-in interface.
- Send your bass drum signal to a bus, here it is Bus 23.
- Adjust the volume of this bus with the volume slider.
- Set the VC 76's key input to receive audio from Bus 23.
- Press PLAY in your sequencer. You should hear the pad's volume being attenuated by the bass drum hits. Tweak the settings on the VC 76 to create a strong or subtle ducking effect.