Effect 2 of 15 · Pedals

The noise gate: silence between the notes

A volume control worked by a detector. Above the threshold it is open; below, it fades the output to nothing.

Play it alone All fifteen effects The whole board

Play it alone

Signal into the board

The test signals are synthesized by this page, sample by sample. Your instrument is asked for only when you press Start with “Your instrument” chosen, with the browser’s echo cancellation, noise suppression and automatic gain control switched off.

Output volume70%

Output levelsilent

Sample rate: not started
Processing latency: not started
Output latency: not started
Input latency: not started
Reported total: not started

Browser audio has latency: you hear each note a little after you play it. These are the browser’s own figures and they leave things out.

What the latency figures mean

The noise gate, alone

In, this one pedal, out. Drag a knob sideways, or focus it and use the arrow keys or the wheel. The whole board has the rest.

Noise gate
Threshold−50 dB
Release60 ms

The signal

What it does to the signal

A gate is a volume control that a level detector operates. While the signal is above the threshold the gate is open and the signal passes at full level. When the signal falls below it, the gate closes and the output fades to silence. It does not take noise out of the notes; it takes away what is left between them.

The detector follows the peaks of the signal: it rises with a time constant of 0.5 ms and falls with one of 15 ms. The gate opens the moment the detector reaches the threshold. It closes only when the detector has stayed 6 dB below the threshold for 30 ms. That gap between the opening level and the closing level, and the wait, are what stop a note that is dying away across the threshold from switching the gate on and off many times a second.

Opening, the gain rises with a time constant of 1 ms. Closing, it falls with the time constant the Release knob sets, all the way to zero.

General definition: Wikipedia, “Noise gate” (revision 1352653007, read 2026-09-28). Everything on this page about how this pedal works describes this page’s own code. It runs as an AudioWorklet processor.

The graph

The graph, drawn.

audiocontrol: moves a setting, is never heard

The detector, the decision and the gain are one AudioWorklet processor; the diagram shows what happens inside it.

The knobs

Every knob, in real units.

Knob	Range	Starts at	What it changes
Threshold	−80 dB to −20 dB	−50 dB	The level, in decibels below full scale, at which the gate opens. It closes 6 dB lower than it opens, so a note dying away across the threshold does not make it chatter.
Release	5 ms to 500 ms	60 ms	The time constant of the fade once the gate has decided to close: in this time the gain falls to 37% of what it was, and in 4.6 times this it falls 40 dB. The gate waits 30 ms under the closing level before it decides.

Measured

What the test measured

Rendered offline, then measured

Switched off and rendered over 48,000 samples of the plucked-string signal, the output was identical to the input in every sample, and the pedal was not in the graph. [as described]
Threshold −50 dB, Release 60 ms. A 1 kHz tone at −60 dBFS never opened the gate: the output peak was zero. [as described]
A 1 kHz tone at −20 dBFS opened it: after the first 100 ms the output was 0.000 dB from the input, and the output first reached 90% of the input’s peak 2.73 ms in. [as described]
After 200 ms of that tone the input fell to −70 dBFS. The output was 20 dB below the input 235 ms later and 60 dB below it 510 ms later. Those 40 dB took 275 ms; a 60 ms time constant predicts 4.6 × 60 = 276 ms. [as described]

Rendered in an OfflineAudioContext at 48,000 Hz in Chrome/154.0.8037.58, 2026-09-29 01:07 UTC. The test is work the page’s builder ran, not something your browser does when you open this page.

Limits

It cannot see the future. The gain starts to rise when the note arrives, not before, so the first couple of milliseconds of every note that opens the gate are turned down (the measurement below gives the figure).
A threshold set too high cuts the tails off notes. A threshold set below the noise never closes.
It closes completely. There is no control for how far down it turns the signal.

Where it goes in the chain

There are two usual places, and they do different jobs. Early, the gate decides on the instrument’s own level, which is the most predictable signal on the board. After the drive pedals, it closes on the hiss they have amplified. This board’s default puts it second. GuitarPlayer’s guide to pedal order does not give the gate a place. The whole order, and the reasons, are on the signal chain page.

← Tuner Octave →

Method

What is computed, and what is read.

Computed here, nothing fetched

Every sound on these pages is computed in your browser by the Web Audio API: 9 of the 15 pedals are graphs of the engine’s standard nodes, 5 are AudioWorklet processors, the wah is both, and the 3 test signals are synthesized sample by sample. No recording is loaded and no data feed is read. The one request the board’s own scripts make is for their AudioWorklet module, a file on labs.llc; the pitch detector is the one the Tuner uses.

Every effect was rendered offline with a known signal and measured: 73 of 73 checks came out as described. Nothing was tested on a real instrument or audio interface, only one browser was used, and nobody listened: the tests measure numbers, not tone. The method, the table of checks and what the latency figures mean are on the about page.

Sources

The W3C Web Audio API 1.1 and Media Capture and Streams specifications (W3C Document License); RFC 9110 and RFC 3986 for the share link’s fragment; GuitarPlayer’s guide to pedal order, quoted briefly; Wikibooks, “Guitar/Effects Pedals”; and each effect’s English Wikipedia article at a named revision (CC BY-SA). All read 2026-09-28; none is fetched by the page.

What happens to what you play

Audio from your input goes into the audio graph and out to your output device, and nowhere else: it is not recorded, stored or sent. Presets and the board as you left it stay in this browser’s local storage. A share link carries the board after the #, which browsers do not send to servers.