Grunge music had a cool idea: Let's take punk simplicity and kind of make it a little more metal. "Fell On Black Days" is the height of this idea.

The guitar core of the song starts out with very low complexity, a pretty, dark blues riff in 6/4, and drums and bass just mirroring the guitar. The only thing higher order is the blues singing by Chris Cornell, one of his signature performances. His ideas and improvisations are so imaginative, finished with diabolical skill.

By the end, we are in a very different song. The backing instrumentation is blasting, metallic guitars escalating low-end chords and drums churning with heavy cymbal and fills. The shrieking vocals here are Chris Cornell's peak as a musician. He hit some superb crescendos after this, but none had the magical authenticity and dramatic timing of "Fell On Black Days."

This song is destined for its crescendo. It's the grunge "White Rabbit."