11
Noise Gate
A noise gate is a type of dynamics processor that mutes or attenuates the input signal until
its amplitude exceeds an adjustable threshold level, at which time the gate ‘opens’ to allow
audio through at its actual level.
They are often used during drum mixing in order to isolate drums within signals containing
bleed or spill from other drums. Another common use is to reduce the decay of toms and
kicks. Noise gates are often referred to simply as ‘gates’.
While BFD2 contains bleed in the kick and snare channels, it can easily be turned off
rather than having to use gates to minimize bleed. Likewise, the decay of kit-pieces can be
adjusted using the damping controls in the kit-piece inspector. However, using gates can be
good for creative effects, or simply for recreating the types of techniques used in real drum
mixing sessions.
BFD2’s Noise gate has a sidechain function, allowing you to create triggered pulsing effects very easily. For example, route any
channel such as a hihat or a user sample direct channel to the master channel’s sidechain input and insert a noise gate in one of
the master channel’s effect slots. Enable the sidechain button for the gate and adjust the threshold until the sidechain input trig-
gers the audio on the channel.
When setting very fast attack and release times, it is common to hear ‘clicks’ in the audio, especially with sounds predominantly
comprised of low frequencies such as kicks and toms – this is totally normal and you simply need to increase these times slightly
to eradicate the problem.
Attack
This controls the speed at which the gate opens once the threshold has been exceeded by the input signal’s amplitude.
Hold
This parameter controls the amount of time the gate remains open after the input signal has dropped below the threshold level.
Release
This controls the speed at which the gate closes at the end of the hold time.
Threshold
This control allows you to set the level at which the gate starts to open. When the input signal amplitude exceeds the level speci-
fied by the Threshold control, the gate starts to open to allow audio through.
SC
Like the compressors, the NoiseGate features a sidechain function. By enabling the SC (Sidechain) button, the gate reacts to the
channel’s sidechain input rather than the main input, while still applying the gating process to the main input. This allows you to
control the gating of the main input signal with another signal entirely.
LP Freq & HP Freq
These controls allow you to filter the input signal used to trigger the gate, while leaving the actual processed signal unfiltered. This
allows you to isolate certain frequencies in the input to improve the gating response – for example, excessive low frequencies in
the input can make the gate react more than required.
It is important to remember that these filters affect only the key signal used to trigger the gate, whether it is the main input or the
sidechain input. They are not applied to the processed signal.
Key Listen
Enabling the Listen button lets you hear the key input being used to trigger the NoiseGate’s amplitude detection circuit instead of
the processed input signal. The key signal can be either the main input or the sidechain input.
It is very useful when using the LP and HP filters and/or the sidechain input.
Hysteresis
Noise gates have a tendency to open and close very quickly when the input signal’s amplitude remains close to the threshold
level for longer periods, something that can result in ‘gate chatter’.
Increasing the Hysteresis control smooths out the gate response to reduce this problem, although the gate becomes less sensi-
tive to small changes around the threshold level.
Mix
With the Mix control at 100%, the BFD2 NoiseGate mutes the signal completely when closed. If you want to let the signal through
at a low level, decrease the Mix control to allow more of the dry signal through.
