Managing Gain Structure Is Key To Audio Quality
When getting into any audio system there will be a few things that are constant and a few things that can vary depending on the gear you are using. One thing will always be extremely important and often overlooked by beginners. We are talking about gain structure. Basically gain structure is creating a bit of consistency from the beginning of the system to the end.
The Basics of Gain Structure
It is common to find users that think gain structure is simply just turning up the gain until it is loud enough or pushing it as hard as you can, when in actuality what you are trying to do is set a consistent level so all outputs can be matched. On an analog console, for example, the goal is to get your input source (whether it be a kick drum or a vocal mic) to be pushing about 0 db of gain or unity gain. You can push harder than 0 db but for this example will say unity to be safe. It is important to remember that the gain is set on the input and shared through all of the outputs. So if you have set you gain to 0 db, each output you decided to send signal to will have a consistent level. If you were to simply turn up the channel fader and then set gain you might be short on power going to the monitor mix or other output feeds.
Setting Gain Structure
When setting gain you must also remember that there is no magic number. Each input device will require a different amount of gain. For example, avocal mic might require less gain than aninstrument mic on a guitar cab. That being said, as you begin your sound check you will want to check all gain levels first. In addition, it is always a good idea to have performers play or sing at their loudest level so gain doesn’t jump up on you. This happens frequently with drummers who can sound check lighter than they perform.
Once your gain is set, you can feel safe that your output signals will be consistent. The concept is very simple, but often ignored when people start to dive into mixing sound. If you can master gain structure you will be able to quickly advance to other more complex mixing situations with greater confidence.