Sidechain compression with Cakewalk

I use the Cakewalk DAW (Digital Audio Workstation) for my musical "experiments". For one composition recently, I wanted to have a "cheesy" DJ intro and a "You've been listening to..." outro. Both of these voice parts would be over the playing song, so I needed to the track itself to "quiet down" when a voice part was active. 

I thought about using volume automation, but that's clumsy and the song itself has quite a few tracks. So it became obvious that using side chain compression was going to be the best approach.

So I've got n tracks that should lower in volume (get compressed) when a voice track is active. It's actually easy to do in Cakewalk once you know how!

First, create a new stereo bus with a compressor in the fx bin (I used the standard Sonitus compressor), and send it out to the master bus. I called it sidechain (perhaps because I lack imagination 😄).

Next, ensure that all tracks and other buses that you want to be compressed are routed through the new sidechain bus. Here's an image of bus to bus, the "Rhythm" and "Bass" buses routed to "sidechain":

Here's an image for some tracks, some of which go direct to the sidechain bus, others routed through intermediate buses - "solo break" goes direct, "Rhythm-R" goes via the "Rhythm" bus, which then goes to the "sidechain" bus: 

The key to making it work is making the the voice track an input to the compressor on the stereo "sidechain" bus. Cakewalk exposes the sidechain input of the compressor as a "send". So if I click on the "Send" plus sign in the voice track, and select the compressor sidechain input menu item, this sets up that association.

As you can see, the voice track goes straight to the master bus. Finally, a few tweaks of the compressor to change the threshold, attack and release times, ratio and knee, and you're done:

There is another way to add a compressor to the bus, without using an existing VST, and it may give more pleasing results depending on your circumstances. The Pro channel 'rack' associated with all tracks and buses allows the addition of a PC4K-S-Type compressor, which has a side chain enable switch; see image below, you can enable that compressor and send the controlling track to its input.