After Effects - Music and Visualization

So after Thursday's class I kept playing around with some of the expressions that we had worked with, and was interested in expanding the music pairing's that we had made. After getting absolutely nowhere for a while, I went onto Youtube and started looking for tutorials of different cool things to do with music in After Effects. I came across these two videos:

I chose to post these two because the music in each varies, so I thought it would be cool to compare them both. I haven't found a tutorial yet, mostly because after I found these I spent a bunch of time watching other music visualizations created in After Effects.