The Noise UI component allows to display a progress bar of the noise with the highest intensity heard by a Perception component, as well as the amount of din.
Update at an Interval
If your game is struggling with performance it is worth changing the Update field from Every Frame to Interval. This will allow to save some precious cycles and improve the performance of the game without barely affecting the gameplay.
The demos included in the Perception module come with a prefab that is ready to be dragged and dropped onto your scene.
If you want to build your own UI it is highly recommended duplicating and modifying the one that comes packed with the module.