How to configure Reaper for a song demo.

When you first run Reaper it has a project loaded to play a song. Here's how to set it up to use a 4x2 (four input, two output) version of AirTraffic Control.

Select track 12, then Track > Insert New Track. This creates track 13 where we'll put AirTraffic Control.

View > Show Routing Matrix. Switch four tracks - Vocals, Lead, Rhythm, and HiHat - from Master/Parent output to track 13 output. Toggle off the 1st column entry and toggle on the entry in the column for track 13.

Hide this matrix by selecting the Mixer tab at the bottom left.

On track 13 click "io". Set Track Channels to 4. There are four "receives" defined already on this form but they aren't quite right yet. Modify them so the first says 1/2 ==> 1, the second says 1/2 ==> 2, the third says 1/2 ==> 3, and the fourth says 1/2 ==> 4.

On track 13 click "fx". Choose the VST effect called "AirTrafficControl".

You are ready to go. Click the Play button in Reaper, then move the avatars around in AirTraffic. You will see/hear how it works.