Far as I know, a noise gate is a device that cuts a signal off once the
input drops below a certain level, its used on mics so that you don't get to
hear the vocalist breathing in too much. Basically, when the singer stops
singing, the noise gate closes, and no input from the microphone is recorded
until the singer starts again, when the gate open.
Most effects like reverb & delay are also gated, to prevent them from
sounding too mushy on the recording. I suppose they can be used to process
samples, is this how Roni Size creates the snapping cut-off effect with the
double bass on 'Brown paper bag'?
Hope this helps,
Tim K.
pp0u7078@liverpool.ac.uk