“Here you have a band that introduced me to the whole harmonic world, which I’d heard a little bit in classical music but never in rock. It had all these kind of cool, suspended chords, based on fourths, that Keith Emerson was so fond of. It probably stemmed from Aaron Copeland, the classical composer.

“Keith would use these chords, but he did it with such character. Instead of playing a major chord, he’d play a sus chord, and it would have a unique vibe to it. I remember hearing this album and then going over to my piano so I could find every fourth chord and sus chord possible. I wanted to be able to land on them without any trouble. I had to figure out what made that sound, and a big part of it was Keith’s harmonic ideas.

“His organ sound was so strong, too, and then you had Greg Lake’s voice along with it. The combination of everything they did was pretty great.”