> For the complete documentation index, see [llms.txt](https://manual.minimal.audio/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://manual.minimal.audio/current-manual/modulation/envelope-follower.md).

# Envelope Follower

***

### Overview

The envelope follower can be used to create modulation signals from nearly any point within the polyphonic synthesis engine. It can track the amplitude of individual sound sources, both pre and post level control, allowing you to apply the dynamics of one sound source onto another, create internal sidechain ducking, and much more.

<figure><img src="https://427345021-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fvbat4pds7C4cELReQ739%2Fuploads%2FzOhBZIy3tWUfzbbUwPfi%2Fmod_follower.png?alt=media&amp;token=a542c9a0-4f63-44e4-b7d8-30034a4f3268" alt=""><figcaption></figcaption></figure>

***

### 1. Input Source

**Follower Source.** Choose which sound source(s) the envelope should follow.

* The **Engine out** option will use all active sound sources after they have passed through the **Engine** filters, but before they pass through the **Effects** rack.
* Individual sound sources are also available, enabling you to create ducking effects between modules.
* The **Post Level** options include the gain from the module's **Level** control, while the **Pre Level** options do not.
* **Sidechain** follows the plugin's sidechain input, so an external track can drive modulation.

***

### 2. Follower Controls

**Invert Level.** When activated, the envelope follower will be inverted, making it easier to use for ducking effects.

**Attack Time.** Set the amount of time it takes for the envelope follower to reach the maximum level of the input signal.

**Release Time.** Set the amount of time it takes for the envelope follower to return to a lower value when the input signal becomes quieter.

**Sync.** Enable BPM synchronization for the envelope follower's attack and release.

**Level.** Scale the follower's output, to attenuate it or to boost it on quiet sources. This will impact the modulation wherever it is assigned.


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