When you drop a beat to your FL Studio playlist, add it to a mixer track. To begin mastering with FL Studio 12, a preferred tool is Maximus. Mixing is adding all tracks to the mixer and leveling all volumes. Mastering is making the track as loud as possible without “clipping,” while still trying to maintain the dynamic range of the song. What is mastering? In FL Studio, mastering is leveling the sound of any audio file, preferably an instrumental.