Detecting an audio "Drop" in unity

Hey guys,

So I am creating my third Unity game for mobile now, and I am stuck on one thing. How can I detect a “Drop” in music that is playing in the background? So for instance, it would be playing a song with an audio listener attached, and then somehow I could possibly be able to measure a difference in the music from what it normally was doing and then it would execute some code?

Thank you for your time, if you need any more information please ask :slight_smile: