I'm a fan of Fortnite game, and the treasure chests sound on gameplay with dimming/amplifying sound effect: getting louder when you get close, is just amazing.

When I hear the sound I know I'm close to a treasure and that leads me to explore.

I wanted to port that experience to the web, the volume increases the closer you are to the action.

You can play with it here, you can also toggle the debug mode for more info.