There are two different techniques for applying mastering processing to a mix: in the Master track of the Set you’re mixing in or in a separate Set just used for mastering. The conventional approach is, of course, to complete the mix then master it separately. However, there are always variations. If I’m doing a quick and dirty master so I can play a track I’m working on at a gig, I’m gonna do the processing right there in the Master track of the mix.
There are some folks out there who don’t believe in separating the process too much. (They’ve probably had too many unpleasant surprises!) I recall reading an interview with Dave Fridman (producer of the Flaming Lips and many others) who often gets credit for mixing and mastering the records he produces. In the interview he said that when the final mix is printed, that’s it. That’s what goes on the CD and nothing happens afterwards. This might be an extreme approach, but it goes to show that there are many ways to get this thing done.
For many engineers, the answer lies somewhere in the middle. This is the approach I’ve taken myself. I do the first 50 – 75% of my mixing with nothing on the master track. Then I usually add in some relatively gentle compression to smooth out the dynamics and help give the mix a more “glued together” sound. As I approach completion, I’ll get a mastering limiter into the mix and sometimes a complete chain including EQ and more compression. This helps me get a feel for what the finished product will sound like, and gives me an opportunity to sort out additional mixing issues.
More on these mixing issues next…