A noise gate turns a sound down, or off, whenever it drops below a level you choose, so the quiet gaps where only noise, hum or bleed lives fall silent while the wanted part passes through untouched. It is the mirror image of a compressor: instead of taming the loud parts, it cleans up the quiet ones.
None of this is tied to one plugin. A gate works from a threshold and a handful of timing controls, so the ideas here apply the same way whatever tool you reach for. The settings below are common starting points, not strict rules.
A noise gate is a tool that turns audio down or off when it falls below a threshold you set, so it silences the quiet gaps where only noise, hum or bleed lives. The wanted part passes through, and the moments between the parts go quiet.
It works by watching the incoming signal against that threshold. While the signal stays above the threshold, the gate is open and the sound passes through untouched. The moment the signal falls below the threshold, the gate closes and turns the sound down or off, so whatever is left in the gap, tape hiss, amp hum, the bleed from another instrument nearby, drops away. When the wanted sound comes back above the line, the gate opens again and lets it through.
The idea is the opposite of a compressor. Where a compressor turns down the parts of a sound that are louder than a threshold, a gate turns down the parts that are quieter than one. A compressor works on the peaks; a gate works on the gaps. That is the whole difference in one line.
A gate does not clean the noise that sits underneath a sound while it is playing. It only removes noise in the gaps, when the wanted sound is not there to open it. Once the part comes back in, whatever hiss or hum was riding along with it comes back too, masked by the louder sound rather than removed. A gate makes the pauses clean, not the notes.
The threshold sets the level a sound has to fall below before the gate closes, and the timing controls, attack, hold and release, set how fast and how smoothly it opens and shuts. A range or floor control sets how far it turns the sound down when it closes, so you can lower the noise rather than mute it completely. Here is what each one does and a sensible place to start.
| Control | What it does | A place to start |
|---|---|---|
| Threshold | The level a signal has to fall below for the gate to close. Above it the gate is open, below it the gate shuts. Set it above the noise in the gaps but below the quietest part you want to keep. | Just above the noise, below the softest wanted note |
| Attack | How quickly the gate opens once the signal rises back above the threshold. Too slow and it clips the front off each note; a fast attack keeps the start of the sound intact. | Fast, so the front of each note is not clipped |
| Hold | How long the gate stays open after the signal drops below the threshold, before it begins to close. This stops it flickering open and shut on a sound that hovers near the line. | Enough to stop it chattering, often tens of ms |
| Release | How quickly the gate closes once the hold time has passed. A fast release cuts tight and abrupt; a slower release fades the tail out so the close is less obvious. | Slow enough that natural tails are not chopped |
| Range or floor | How far the gate turns the sound down when it is closed. Set it to full for total silence, or to a partial reduction to just lower the noise rather than mute it. | A partial cut, quieter but not silent, often sounds more natural |
Attack and release are what give a gate its feel. A fast attack lets the sharp front of a note through the instant it crosses the threshold, which keeps a snare or a plucked string sounding crisp; too slow an attack and the gate is still opening when the hit arrives, so the front gets softened or clipped. Release decides the other end: a quick release snaps the gate shut for a tight, deliberate cut, while a longer release lets the sound fade as the gate closes, so the tail is not lopped off in a way the ear notices.
The common problem is chattering, where a sound sits right at the threshold and the gate rapidly opens and closes on it, which sounds like stuttering. The hold control is the main cure, keeping the gate open long enough to ride over those wobbles, and many gates add a small amount of hysteresis, a gap between the level that opens the gate and the lower level that shuts it, for the same reason. A range or floor that only turns the sound down part way, rather than cutting it to full silence, also hides the switching and usually sounds more natural.
Reach for a gate when a recording has noise, hum or bleed in the gaps between the parts you want, or when you want to tighten a sound by cutting its tail short. In short, whenever the problem lives in the quiet moments rather than the loud ones. The common jobs:
Gating is most at home on recorded, noisy sources, a mic in a room or an amp with a hum. A clean source, such as a software instrument, rarely needs it, because its gaps are already silent. Small moves tend to win: set the threshold just high enough to catch the noise, and lean on a partial range rather than a hard mute when you can, so the gate does its job without announcing itself.
One famous use is not cleanup at all. Put a big reverb on a drum and then a gate straight after it: the reverb tail blooms out huge, and the gate slams shut partway through, so the sound is enormous but stops dead instead of ringing on. That abrupt, slammed shut snare is one of the signature drum sounds of 1980s records, and it is still reached for when a drum needs to sound big without washing over the next beat.
A gate and an expander do the same job, turning quiet audio down, but a gate does it abruptly while an expander does it gently. An expander is the softer, ratio-based version of the same idea: instead of snapping fully shut below the threshold, it turns the sound down by a ratio, so a little below the threshold means a little quieter and further below means quieter still.
A hard gate is really an extreme setting of that same behaviour. Below the threshold it drops the level right down, often all the way to silence, in one step. That is decisive and useful when you want a part to stop dead, but it can sound obvious, cutting in and out. An expander eases into it instead: for every dB the signal falls under the threshold it turns down by a set ratio, so the reduction grows smoothly as the sound gets quieter. That gentler action tends to sound more natural on parts where a hard cut would be too blunt, like a breathy vocal or a note with a long, soft decay.
In practice the line between the two is blurry. Many plugins labelled as gates are really expanders with a range control, and setting an expander to a steep ratio and a low floor turns it into a gate in all but name. It helps to think of a gate as an expander turned up to its most extreme: reach for the gentle end when you want to reduce noise without it being noticed, and the hard end when you want a sound to stop completely.
Gate and expander are not rival tools so much as two ends of one dial. Both listen for a threshold and turn down whatever falls below it; the only real question is how steeply. Pick the gentle end to tidy up noise you would rather not hear, and the steep end when you want a clean, deliberate cut. Neither removes noise from under the wanted sound, so both work best on a source that was reasonably clean to begin with.
A gate is a repair tool. It matters when a recording came in with noise, hum or bleed in the gaps, and the honest truth is that a clean source rarely needs one at all. Fixing a messy recording is a real job; not making the mess in the first place is a better one.
We do not sell a gate plugin, so this is not a pitch for one. But it is worth saying plainly: The Collection is our three instruments together, ARGISH, SILT and REHEAT, with three separate licence keys, and they are clean digital sources. There is no mic, no amp hum and no room bleed, so the gaps between notes are already silent and there is nothing to gate out in the first place. ARGISH is a self-playing drone synth, SILT is a tape-loop instrument, and REHEAT writes acid lines, and whatever you make with them is yours to release. Each one ships as AU, VST3, AAX and a standalone app on macOS, signed and notarized, and a VST3 on Windows.
You can hear one free in your browser first, no install and no account, then decide.
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