This is a paid asset, but now you can download Visualizer Studio Free.
Detail this asset from Unity Store: Original Link
Visualizer Studio v1.4.4 (Latest version)
Version 1.4.0 and later now includes ALL source code!
Works with Unity 3.5, Unity 4, Unity 5, Unity 2017, and Unity 2018!
Visualizer Studio is a Unity Scripting Package which enables the developer to allow their game to react to music and sound effects. It exposes easy to use, powerful, and expandable base classes and interfaces that perform a lot of the difficult tasks of audio visualization. Using Visualizer Studio allows your game to create a range of effects, from trees that subtly sway to the music, to controlling all gameplay with the music!
Tutorials and more can be found on our website!
Altered Reality Website
If you want support for internet radio and more, please check out the amazing plugin, Radio! It works great with Visualizer Studio!