@maruaudio/dsp/dynamics/gate is a soft envelope gate: an absolute-value detector, a one-pole smoothed envelope e = c·e + (1 − c)·|x|, a logistic comparator g = 1 / (1 + exp(−60·(clamp(e) − clamp(threshold)))) with both terms clamped to 0 to 1, and a VCA y = x·g. The envelope is rounded to f32. The smoothing coefficient is exp(−1 / (t·rate)) with the gate's own bounds (t 0.0001 to 2 s, rate 8 to 384 kHz).

const state = initGateNode(48000)
setGateThreshold(state, -50)
const y = gateNodeTick(state, x)

Parameters

The logistic steepness is the constant GATE_STEEPNESS (60).

Lifecycle

initGateNode(sampleRate) → setters → gateNodeTick → resetGateNode, which zeroes the envelope and keeps the settings. prepareGateNodeSampleRate re-derives the coefficient from the stored smoothing time without allocating.

When to use it

Quieting the space between notes on a noisy guitar, drum or vocal track. The logistic curve fades the gain around the threshold instead of switching it.

Limits

• Mono sample tick. One smoothing time serves both opening and closing; there is no hold, range floor or lookahead.
• The comparator compares linear levels; at the threshold the gain is 0.5.
• Clamps are the kernel node's conditional clamp, not @maru/math-range.
• audio-kernels keeps the PCM16 render entries.