Use Noise Gate in Logic Pro for iPad
Set the Reduction knob to the lowest possible value to make sure that sounds below the Threshold value are completely suppressed. Set to a higher value to reduce low-level sounds but still allow them to pass. You can also use the Reduction knob to boost the signal by up to 20 dB, which is useful for ducking effects.
The Attack, Hold, and Release knobs modify the dynamic response of Noise Gate. If you want the gate to open extremely quickly for percussive signals such as drums, set the Attack knob to a lower value. For sounds with a slow attack phase, such as string pads, set Attack to a higher value. Similarly, when working with signals that fade out gradually or that have longer reverb tails, set a higher Release knob value that allows the signal to fade out naturally.
The Hold knob determines the minimum amount of time that the gate stays open. You can use the Hold knob to prevent abrupt level changes—known as chattering—caused by rapid opening or closing of the gate.
The Hysteresis knob provides another option for preventing chattering, without needing to define a minimum Hold time. Use it to set the range between the threshold values that open and close the gate. This is useful when the signal level hovers around the Threshold level, causing Noise Gate to switch on and off repeatedly, thus producing the undesirable chattering effect. The Hysteresis knob essentially sets the gate to open at the Threshold level and remain open until the level drops below another—lower—level. As long as the difference between these two values is large enough to accommodate the fluctuating level of the incoming signal, Noise Gate can function without creating chatter. This value is always negative. Generally, −6 dB is a good place to start.
In some situations, the level of the signal you want to keep and the level of the noise signal may be close, making it difficult to separate them. For example, when you’re recording a drum kit and using Noise Gate to isolate the sound of the snare drum, the hi-hat may also open the gate in many cases. To remedy this, use the side chain controls to isolate the desired trigger signal with the High Cut and Low Cut filters.
Important: The side chain signal is used only as a detector/trigger in this situation. The filters are used to isolate particular trigger signals in the side chain source, but they have no influence on the actual gated signal—the audio being routed through Noise Gate.
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