# Fmod instance vs Fmod Audio component **URL:** \ **Category:** Unreal Engine\ **Created:** [December 18, 2021, 12:22am UTC](https://qa.fmod.com/t/fmod-instance-vs-fmod-audio-component/18115 "2021-12-18T00:22:35Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![zackregansounds](https://avatars.discourse-cdn.com/v4/letter/z/b5e925/32.png) [@zackregansounds](https://qa.fmod.com/u/zackregansounds)\ **Post date:** [December 18, 2021, 12:22am UTC](https://qa.fmod.com/t/fmod-instance-vs-fmod-audio-component/18115/1 "2021-12-18T00:22:36Z")
What exactly is the difference between these two and when should I use them? I am making my own occlusion system, bc I dont like unreals. ---
**Author:** ![Alcibiade](https://yyz2.discourse-cdn.com/flex036/user_avatar/qa.fmod.com/alcibiade/32/4284_2.png) [@Alcibiade](https://qa.fmod.com/u/Alcibiade)\ **Post date:** [December 18, 2021, 3:21pm UTC](https://qa.fmod.com/t/fmod-instance-vs-fmod-audio-component/18115/2 "2021-12-18T15:21:41Z")
Though I don’t really get the logic behind, the differences I’ve noticed are: FMOD component is the more convinient for moving sounds. The actor transform is automatically updated, to be used by the spatializer. FMOD component is the only way to use callbacks (unfortunately). FMOD instances are more convinient if you have to keep track of individual instances, like for stacking and pooling instances (though it may also be possible to pool audio components). If you don’t want callbacks or a moving sound, you probably should use instances. ---
**Author:** ![zackregansounds](https://avatars.discourse-cdn.com/v4/letter/z/b5e925/32.png) [@zackregansounds](https://qa.fmod.com/u/zackregansounds)\ **Post date:** [December 20, 2021, 7:56pm UTC](https://qa.fmod.com/t/fmod-instance-vs-fmod-audio-component/18115/3 "2021-12-20T19:56:56Z")
Thank makes a lot of since thank you