> For the complete documentation index, see [llms.txt](https://emotiv.gitbook.io/emotivpro-builder/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://emotiv.gitbook.io/emotivpro-builder/building-an-experiment-in-builder/audio-overlay-soundtrack.md).

# Audio overlay (soundtrack)

Individual audio files can be added to each phase of an experiment and act as a soundtrack over other elements. 

You also have the option to customize audio files in your experiment. You can:

* loop an audio file several times during a phase; or 
* choose when you want an audio file to stop in a phase. 

If you don't loop an audio file or its duration is shorter than the duration of the phase, it will stop at the end of the file and not re-play.\
\
To add an audio file to a stimuli phase, click on the **Settings** button, then select **Audio Overlay**.

![](https://lh3.googleusercontent.com/bgm1m2jXT4e8ITF4Ce12COXrmB4bRA5f2Nphl1qQF32iZCKkGURe4geBnvZ2cf8b8HS1v9KADLy9KiaQk76j4vq7I-7hZy2RuMt4rSEgZyGhAK2ZJt2TENS5_l8eJru6hcGKqVGF=s0)


---

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