This post is geared to all recording artists who own their own DAWs and mix their own material. It provides some insight into a commonly over-looked mixing issue which I refer to as “gain structure.” Gain structure is the amount of gain (volume increase) on a music track at each point it can be attenuated. For instance, if you have a vocal track, the volume of the vocals can be increased by any number of plug-ins, the channel fader, the auxiliary input if applicable, the bus input, and the master fader. Where the volume is set at each of these stages is what I refer to as the “gain structure.”
What most artists do not realize is that the more tracks you record, the more you have to pay attention to where you are boosting signals. It is a common practice to record a track, set it at a reasonable level and continue over-dubbing. As overall volume increases as a result of more tracks, then the master fader is typically turned down or possibly the sub mixes are lowered to compensate for headphone levels or speaker outputs. Once all the tracks are recorded the mixing will then ensue with fader levels all over the place.
Each DAW has its own mixing algorithm and will be sensitive to overall gain structure!
Lets do an experiment. Take a session that has 10 plus tracks, remove all plugins, and make a copy of it. With the first session, call it session “A”, we will set the master fader, every bus, and every send at 0db. Then lower all the track faders to -20db and try to reach a good mix without touching the master faders, buses and sends. Be CAREFUL not to push overall levels past 0.0db. OK got it? Now lets got to session “B.” With this copy we will set the buses, and sends to 0.0 and the master fader to +10db. Now begin your mix and try to obtain the same overall feel. You will notice that you wont need near as much attenuation from your individual track faders with the master fader so high. Try to get the mix similar and the overall master fader hitting at the same amplitude. Hopefully you can get the mix close.
Next, bounce both tracks down and compare. The results will vary depending on your DAW, but I am confident you will notice a difference and in some cases a significant difference. Which is better? You be the judge. But consider this, when you begin to add plugins on your buses and master fader which are sensitive to their input levels you can see how important an understanding of gain structure really is. Again, each system is a little different but take note of your good mixes and figure out where you are pushing the signal and where you are not, and learn from it. There is no magic answer or technique but if you pay attention to your gain structure you will start to see a trend and develop a good mixing method that is best for your DAW.