We’re still talking about mastering here, but this tip includes a cool technique that you may find other uses for..
When I’ve inserted my mastering chain into the mix, I sometimes like to use Spectrum to have a look at the difference between my mix and the track I’m referencing. This presents an interesting problem.
I want to put spectrum into the Master track, so I can quickly switch back and forth between my mix and the reference track while watching the graph. The problem is that I need to avoid running the reference track through the mastering chain. (As you may recall, I tend to run my reference track directly out of Ext. Out 1/2 to avoid listening to it through any devices on the Master track.)
The solution to this problem is a little trick using Compressor – not as a compressor, but as a tool that allows you to insert any signal anywhere. Drop the Compressor after the mastering chain, and before Spectrum.
Open up the Sidechain section and set the source to the reference track.
Then, use the Preview switch to monitor the reference track.
You’ve now silenced the audio flowing into the Master track, and replaced it with the reference track. Now you can switch back to your mix by turning the Compressor off.