# Timeline Callback for emitters

**URL:** <https://qa.fmod.com/t/timeline-callback-for-emitters/21062>\
**Category:** Unity\
**Created:** [January 5, 2024, 5:52pm UTC](https://qa.fmod.com/t/timeline-callback-for-emitters/21062 "2024-01-05T17:52:41Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![JackTheRobot](https://avatars.discourse-cdn.com/v4/letter/j/58f4c7/32.png) [@JackTheRobot](https://qa.fmod.com/u/JackTheRobot)\
**Post date:** [January 5, 2024, 5:52pm UTC](https://qa.fmod.com/t/timeline-callback-for-emitters/21062/1 "2024-01-05T17:52:41Z")

</div>

Is there any documentation for timeline callbacks and emitters? I suppose a further question is should I be moving away from using emitters and towards creating instances in script? There seems to be much more documentation around instances than emitters

---

<div class="post-metadata">

**Author:** ![Leah\_FMOD](https://yyz2.discourse-cdn.com/flex036/user_avatar/qa.fmod.com/leah_fmod/32/3685_2.png) [@Leah\_FMOD](https://qa.fmod.com/u/Leah_FMOD)\
**Post date:** [January 7, 2024, 11:25pm UTC](https://qa.fmod.com/t/timeline-callback-for-emitters/21062/2 "2024-01-07T23:25:10Z")

</div>

Unfortunately, we do not currently have any documentation regarding using timeline callbacks with event emitters. Event emitters are designed to manage the lifetime of a single event instance, and are relatively constrained in the scope of functionality they provide.

If you intend to make use of timeline callbacks, I would recommend creating instances in your own scripts and using our [Timeline Callbacks example](https://www.fmod.com/docs/2.02/unity/examples-timeline-callbacks.html) as a reference. However, if you still want to make use of event emitters, you could instead modify their source at `./Assets/Plugins/FMOD/src/StudioEventEmitter.cs` and add the required functionality.