Gate Normalized Amplitude

After NormalizeAmplitude you have a 0-to-1 curve where even the quiet parts are some nonzero number. GateNormalizedAmplitude is a threshold that makes a decision: anything below gate_normalized becomes exactly 0, anything above it passes through unchanged. The result is a burst signal - it's either "on" with the music or flatline silent - rather than a smooth gradient.

That's a genuinely different shape, and it's the right shape for a whole class of effects. If you want to switch a prompt or kick a strength parameter only when the track is actually hitting - not when it's merely audible - gating gives you a clean on/off instead of a mush where everything is technically nonzero. It's the binary version of NormalizedAmplitudeDrivenString's thresholding, useful when you want the amplitude itself (not a prompt list) to do the switching.

Inputs and output

• normalized_amp (NORMALIZED_AMPLITUDE) - the curve to gate.
• gate_normalized (float, 0–1, default 0) - the threshold. Values above it survive; everything at or below it becomes 0.

Output: normalized_amp, same type and length.

The code is a single comparison: np.where(normalized_amp > gate_normalized, normalized_amp, 0.0). That's it - no smoothing, no hysteresis, just the threshold. Which means the output can still flutter if the curve is noisy right around your threshold value. If you see that, run TransientAmplitudeBasic (or at least ClipAmplitude) before gating to tidy the curve.

Gotchas

The default gate_normalized is 0, and at 0 nothing gets zeroed - the node is a pass-through until you raise the threshold, which confuses people who plug it in, see no change, and assume it's broken. It's not; it's doing exactly what a gate at zero does. Also remember this operates on the normalized 0–1 curve, so your threshold lives in that space: 0.5 means "only the louder half of the track gets through."

Install: ComfyUI Manager search ComfyUI-AudioScheduler, or git clone https://github.com/a1lazydog/ComfyUI-AudioScheduler into custom_nodes and restart. CPU-only, no models.