Strangelight AudioEnvelope Follower
Tracks the amplitude envelope of an incoming audio signal and emits a remapped control value.
Tracks the amplitude envelope of an incoming audio signal and converts it into a smooth control value for driving modulation. Attack and release smoothing set how quickly the follower rises to transients and falls back on decays, and the detected level is remapped to a usable range so it can modulate filter cutoff, gain, pan, or any other target. Typical uses include auto-wah, ducking, and audio-reactive control.
Inputs
Audio In
Audio signal input
| ID | audio |
|---|---|
| Signal | audio · audio rate · stereo |
| Unit | normalized |
| Range | -1 to 1 normalized |
| Default | 0 |
| Coercion | Implicit |
Outputs
Value
Envelope follower output remapped between Out Min and Out Max.
| ID | value |
|---|---|
| Signal | control · control rate |
| Unit | normalized |
| Coercion | Implicit |
Parameters
Input Level
Pre-gain applied to the incoming signal before envelope detection.
| ID | inputLevelDb |
|---|---|
| Type | float |
| Control | slider |
| Range or Options | -24 to 24 dB, step 0.1 |
| Default | 0 |
| Group | Input |
Threshold
Gate threshold for the detector. Higher values require a louder input to open.
| ID | thresholdDb |
|---|---|
| Type | float |
| Control | slider |
| Range or Options | -60 to 0 dB, step 0.1 |
| Default | -60 |
| Group | Input |
Attack
How quickly the follower rises when the input level increases.
| ID | attackMs |
|---|---|
| Type | float |
| Control | slider |
| Range or Options | 0.1 to 1000 ms, step 0.1, log |
| Default | 10 |
| Group | Envelope |
Release
How quickly the follower falls when the input level decreases.
| ID | releaseMs |
|---|---|
| Type | float |
| Control | slider |
| Range or Options | 1 to 3000 ms, step 1, log |
| Default | 120 |
| Group | Envelope |
Out Min
Minimum remapped output value.
| ID | outMin |
|---|---|
| Type | float |
| Control | slider |
| Range or Options | -1 to 1 normalized, step 0.01 |
| Default | 0 |
| Group | Range |
Out Max
Maximum remapped output value.
| ID | outMax |
|---|---|
| Type | float |
| Control | slider |
| Range or Options | -1 to 1 normalized, step 0.01 |
| Default | 1 |
| Group | Range |
Details
| Canonical ID | an.envelopeFollower |
|---|---|
| Category | analysis |
| Runtime Surface | audio |
| Runtime Targets | audio-worklet |
| JUCE Early Access | Supported |
| Early Access Note | Native-supported in the plugin for the current catalog/runtime support contract. |
| Audio Channel Behavior | Analyze / Reduce (audio → control, or terminal sink) |
| Stereo Reduction | left channel only |