Hit play to loop a speech sample with noise and try to adjust the threshold to mute the otherwise audible noise in between speech segments.
Sound registering beneath the threshold level will be muted. Threshold is measured in dBFS (decibels relative to full scale), where 0 is the maximum level, and -6 dBFS is 50% of the maximum level.
Attack controls how long time it takes (in seconds) for the noise gate to mute the sound once it registers beneath the threshold. Release controls how long time it takes (in seconds) for the noise gate to unmute the sound once it registers above the threshold. In both cases, the volume linearly changes to its new value.
With the noise volume set at 1, the noise gate should mute noise in between pauses at a threshold of -40db. If you hear glitching, try adjusting the attack and release settings.
If your browser supports the AudioWorklet node, you can switch between the ScriptProcessor and AudioWorklet NoiseGate implementations.
Noise Gate is