PROCESSING AND EFFECTS

GATING / EXPANSION

GATE / EXPANDER

A gate is an automatic mute that can be set to turn on or off when the sound reaches a certain loudness threshold.  This can be used for removing background noise on a track with a loud instrument, or even to change the attack (beginning) of a sound.  For example, if you put a gate on a sound that started from silence and slowly became louder, it would remain silent and then suddenly be heard once it reached the threshold.  If a sound that faded out was put into a gate it would suddenly cut off when it became quieter than the set threshold. 

Gates can be set to open and close quickly or slowly.  They can even be triggered from another source (called an EXTERNAL KEY), allowing you to make a long sustaining sound follow the rhythm of another part.  Gates can make sounds begin or end in an unnatural way.

An EXPANDER works like a very soft gate, sort of the reverse of a compressor.  Instead of being OFF when sound is below the threshold, it allows sound through but reduced in volume (a partially opened gate).  As the sound approaches the threshold level more of the sound is allowed through until it is 100% open.