The microphone gate is a physical gate right behind the sound board. The gate is a very useful tool to use when in any recording environment, it can be used to help you get a crystal clear recording the first time around. The way a studio microphone works is it picks up certain ranges of frequencies better than others and most of the frequencies that your voice puts off are higher than the frequencies of the ambient noise of the room. This can cause a constant hum in the recording basically making it unusable.
The gate works to eliminate that noise by cutting out the lower bass tone out of your recording. A gate is very simple to use, you just turn the dial until you hear the hum disappear. Then re-listen to the recording because you may have taken it too far and cut out some of the bass tones in the track that you would’ve wanted there.