How to set up sidechain compression in Cubase SX3
This is just a quick one to show you how it's done, because I get asked about it a lot by confused people
Get hold of the plugin
The sidechaining compressor I use is the imaginatively titled "Side Chain Compressor" by Slim Slow Slider which is free and perfectly up to the job. Download it and install it to a suitable place in your vstplugins folder.
Setting up the sidechain bus
Because Cubase SX3 has no notion of a sidechain included as part of the plugin architecture, you must set up a special bus for the effect to go through. As you want to sidechain a stereo signal against another stereo signal, we need 4 inputs to the plugin, so we need a quadrophonic group channel
To add this, select Project->Add Track>Group Channel, then you will see this box:
Select Quadro from the "More..." selection and press ok
Splitting the Quadro bus into 2 stereo children
This is the part that people usually miss out, and it's what makes the whole thing work.
Open up the Devices-> VST Connections dialog and go to the Group/FX tab. You should see your newly created group channel there.
Right click on the group and select Add Child Bus->Stereo, then repeat with Stereo (Ls Rs). This will create separate buses for the front and rear channels of the quadrophonic group, and allow them to be treated as separate inputs.
Routing the signals
Now all thats left to do is to connect everything up:
- Set the signal you want compressed to be sent to the "Stereo" section of the Quadro group as the output path.
- Add a send to the signal you want as the sidechain input and route it to the "Stereo (Ls Rs)" section of the Quadro group.
- Add the "SideChCompSt" plugin as an insert to the Quadro group.
You should now be in business. All you now need to do is tweak the compressor settings to get the desired sound.