A gate is an audio processing tool that is used to control the level of an audio signal.
The gate attenuates (reduces the level of) the signal when it falls below a certain threshold. The threshold is set so that only the desired signal is passed through while unwanted noise is suppressed. This means that the signal will only be heard at all when it exceeds the minimum threashold.
Gates can be used to control the level of any type of audio signal, but they are most commonly used with microphones. When using a gate with a microphone, the gate can be used to reduce or eliminate background noise and bleed from other instruments.
Gates typically have two controls: threshold and release. The threshold control sets the level at which the gate will start to attenuate the signal. The release control sets the amount of time it takes for the gate to return to its normal state after the signal falls below the threshold.
Audio gates are a valuable tool for controlling audio levels in any situation where unwanted noise needs to be eliminated. By setting the proper threshold and release settings, gates can help to ensure that only the desired signal is amplified or recorded.