Noise
Gate is a soft effect that can be used to lower or remove the perceptible
level of noise in an audio signal from an audio segment. A noise
gate does not remove noise from the audio signal.
A noise gate is commonly
used when the level of the desired signal generally stays above
the level of the noise. In this case, the threshold is set above
the level of the noise. When the level of the signal remains above
the threshold level, the gate is open and both the signal and the
noise are allowed to pass through.When the level of the signal falls
below the threshold level, the gate is closed and no signal is allowed
to pass. In effect the perceptible noise is attenuated.
The Noise Gate soft effect
has the following controls.
| Control |
Values |
Description |
| Threshold |
-96 dB - 0 dB |
Determines the level at which the noise gate stays open. Signals
exceeding the Threshold pass through unaffected. Signals not meeting
the Threshold are attenuated based on the Ratio and Floor settings.
|
| Ratio |
1:1 - 20:1 |
Defines the amount of gain reduction applied to the signal below
the Threshold level. For example, a Ratio of 2:1 means that for
every 2 dB the input signal increases, the output signal will only
increase by 1 dB.
|
| Attack |
0.01 ms - 10 ms |
Defines the speed at which the gate will open when the audio
level goes above the Threshold. A short attack rate means that the
early part of the signal will not be attenuated. If the attack time
is too short a click can be heard when the gate opens. A long attack
rate means that most of the early part of the signal is attenuated.
The result can be more natural sounding than using a short Attack.
|
| Hold |
0 ms - 1000 ms |
Defines the minimum time that the gate will stay open.
A longer hold time can help avoid chattering by preventing the gate
from closing prematurely. For example when used with speech, the
short pauses between words or sentences will not cause the gate
to close.
|
| Release |
10 ms - 2000 ms or Auto
|
Defines how quickly the gate will close once the level
has dropped below the threshold. A larger release value allows for
a smooth decay rather than an abrupt cut when the gate closes.
|
| Floor |
-96 dB - 0 dB |
Defines the amount of attenuation when the gate is closed. |
| Output Gain |
-60dB - 24 dB |
Defines the amount of gain to add to the output signal. |
