# Feature request: Envelope follower or control parameter with sidechain **URL:** \ **Category:** FMOD Studio\ **Created:** [May 25, 2020, 10:17pm UTC](https://qa.fmod.com/t/feature-request-envelope-follower-or-control-parameter-with-sidechain/15813 "2020-05-25T22:17:56Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Tomavatars](https://yyz2.discourse-cdn.com/flex036/user_avatar/qa.fmod.com/tomavatars/32/49_2.png) [@Tomavatars](https://qa.fmod.com/u/Tomavatars)\ **Post date:** [May 25, 2020, 10:17pm UTC](https://qa.fmod.com/t/feature-request-envelope-follower-or-control-parameter-with-sidechain/15813/1 "2020-05-25T22:17:56Z")
Hello there! I’m surprised that there are not more topics about this feature. I would like to be able to internally control a parameter with an envelope follower module. Do you plan something like this? ---
**Author:** ![thuan](https://yyz2.discourse-cdn.com/flex036/user_avatar/qa.fmod.com/thuan/32/261_2.png) [@thuan](https://qa.fmod.com/u/thuan)\ **Post date:** [May 26, 2020, 2:09am UTC](https://qa.fmod.com/t/feature-request-envelope-follower-or-control-parameter-with-sidechain/15813/2 "2020-05-26T02:09:47Z")
Hi there, Not entire sure if we are referring to the same end result, but looking at various description of envelope follower it sounds similar to our sidechain modulator? Noting in 2.1 we have added the Peak/RMS mode to the sidechain modulator as well. Let us know if it is something else you have in mind. ---
**Author:** ![Tomavatars](https://yyz2.discourse-cdn.com/flex036/user_avatar/qa.fmod.com/tomavatars/32/49_2.png) [@Tomavatars](https://qa.fmod.com/u/Tomavatars)\ **Post date:** [May 26, 2020, 12:28pm UTC](https://qa.fmod.com/t/feature-request-envelope-follower-or-control-parameter-with-sidechain/15813/3 "2020-05-26T12:28:56Z")
I’m so sorry @thuan, what a waist of time for you! That has been some time I haven’t dig and experience in Fmod, more occupied by coding our game, I missed this implementation. This is absolutely fantastic! Thanks! I would have a suggestion, concerning command modules. Would it be possible to create a trigger module, like the Timeline Callbacks are working? Meaning that for example, when the parameter has a certain value, it can trigger an event in UE4? As we can’t add markers in a parameter sheet, this would be helpful. And in many other cases as well. Congratulations for all the great features you added in the past months, I can’t praise enough Fmod when speaking with other sound designers! ---
**Author:** ![thuan](https://yyz2.discourse-cdn.com/flex036/user_avatar/qa.fmod.com/thuan/32/261_2.png) [@thuan](https://qa.fmod.com/u/thuan)\ **Post date:** [May 26, 2020, 11:41pm UTC](https://qa.fmod.com/t/feature-request-envelope-follower-or-control-parameter-with-sidechain/15813/4 "2020-05-26T23:41:46Z")
Hi @Tomavatars, not a problem, glad to hear we have covered the feature you had in mind. Just to clarify, do you mean trigger an FMOD event (i.e. start a particular event) in UE4 or do you mean to have a callback that the user is free to execute some functionality in UE4? ---
**Author:** ![Tomavatars](https://yyz2.discourse-cdn.com/flex036/user_avatar/qa.fmod.com/tomavatars/32/49_2.png) [@Tomavatars](https://qa.fmod.com/u/Tomavatars)\ **Post date:** [May 29, 2020, 6:31pm UTC](https://qa.fmod.com/t/feature-request-envelope-follower-or-control-parameter-with-sidechain/15813/5 "2020-05-29T18:31:48Z")
@thuan I mean to have a callback ---
**Author:** ![LunaRyuko](https://yyz2.discourse-cdn.com/flex036/user_avatar/qa.fmod.com/lunaryuko/32/2086_2.png) [@LunaRyuko](https://qa.fmod.com/u/LunaRyuko)\ **Post date:** [April 8, 2021, 4:28pm UTC](https://qa.fmod.com/t/feature-request-envelope-follower-or-control-parameter-with-sidechain/15813/6 "2021-04-08T16:28:52Z")
Hey! Sorry for reviving an old thread, but this is also a feature I have need of. I really want to use FMOD, but the lack of this feature that exists in vanilla UE4 really bothers me and I want to avoid using both audio systems. What the Audio Component’s Envelope Follower does in UE4 is it basically calls an event that passes the envelope value which can be used for simple procedural lipsync ([Video example here](https://www.youtube.com/watch?v=4oDbkNVHTdw)) This is how I’ve set up that lipsync. Obviously I plan to make a bit of a different system for that, but the way I want to do it is basically the same. ![UE4Editor_ucDDrHCstj](https://canada1.discourse-cdn.com/flex036/uploads/fmod/original/2X/4/4f318e8a41519f23b56a515e8f51b33b3567401a.png) ---
**Author:** ![joseph](https://yyz2.discourse-cdn.com/flex036/user_avatar/qa.fmod.com/joseph/32/264_2.png) [@joseph](https://qa.fmod.com/u/joseph)\ **Post date:** [April 27, 2021, 5:10am UTC](https://qa.fmod.com/t/feature-request-envelope-follower-or-control-parameter-with-sidechain/15813/7 "2021-04-27T05:10:38Z")
> [@LunaRyuko](#): > > What the Audio Component’s Envelope Follower does in UE4 is it basically calls an event that passes the envelope value which can be used for simple procedural lipsync ([Video example here](https://www.youtube.com/watch?v=4oDbkNVHTdw)) As of the time of writing (April of 2021), we do not support getting the output value of a sidechain effect or envelope follower DSP effect. In code, you could potentially use [DSP::getMeteringInfo](https://www.fmod.com/resources/documentation-api?version=2.2&page=core-api-dsp.html#dsp_getmeteringinfo) to get the metered output of a DSP unit. This feature isn’t available through blueprints, but can be accessed via code. Would that serve your purposes? Alternatively, you could instead put a sidechain modulator on a parameter, link the modulator to a sidechain somewhere in your FMOD Studio project and use the value of the parameter. ---
**Author:** ![LunaRyuko](https://yyz2.discourse-cdn.com/flex036/user_avatar/qa.fmod.com/lunaryuko/32/2086_2.png) [@LunaRyuko](https://qa.fmod.com/u/LunaRyuko)\ **Post date:** [April 27, 2021, 2:04pm UTC](https://qa.fmod.com/t/feature-request-envelope-follower-or-control-parameter-with-sidechain/15813/8 "2021-04-27T14:04:34Z")
Thank you! I’ll check out both of the things you mentioned!