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Noise Gate
The Noise Gate is commonly used to suppress unwanted noise that is audible when the
audio signal is at a low level. You can use it to remove background noise, crosstalk from
other signal sources, and low-level hum, among other uses.
The Noise Gate works by allowing signals above the threshold level to pass unimpeded,
while reducing signals below the threshold level. This effectively removes lower-level
parts of the signal, while allowing the desired parts of the audio to pass.
Noise Gate Parameters
The Noise Gate has the following parameters.
• Threshold slider and field: Sets the threshold level. Signals that fall below the threshold
will be reduced in level.
• Reduction slider and field: Sets the amount of signal reduction.
• Attack knob and field: Sets the amount of time it takes to fully open the gate after the
signal exceeds the threshold.
• Hold knob and field: Sets the amount of time the gate is kept open after the signal falls
below the threshold.
• Release knob and field: Sets the amount of time it takes to reach maximum attenuation
after the signal falls below the threshold.
• Hysteresis slider and field: Sets the difference (in decibels) between the threshold values
that open and close the gate. This prevents the gate from rapidly opening and closing
when the input signal is close to the threshold.
• Lookahead slider and field: Sets how far ahead the Noise Gate analyzes the incoming
signal, allowing the effect to respond more quickly to peak levels.
81Chapter 4 Dynamics Processors