Gain structure plays a great importance in audio system especially when you deal with sound reinforcement system. If you don not understand gain structure works then you won’t be able to get the optimum clean sound from your PA system.
To begin with, it is a good practice if you start looking at gain structure surrounding a mixing console.
You must always be aware of the gain structure surrounding a console. Look at the gain structure and how it works.
and adjust your gain at the mic preamp