Progressive Rock

Yes in concert, 1977. Rick Dikeman, CC BY-SA 3.0 <http://creativecommons.org/licenses/by-sa/3.0/>, via Wikimedia Commons

Diligently searching for a clear definition of progressive rock, I happened upon this excerpt in a Master Class article entitled “Progressive Rock Guide: A Brief History of Progressive Rock.” The author or authors identified six characteristics of progressive rock:

Musical ambition: Sophisticated harmonies, mixed time signatures, and multi-part songwriting can be found on albums ranging from Yes’ Close to the Edge to Dream Theater’s The Astonishing.
Expanded instrumentation: Prog rock bands often push beyond the traditional rock instrumentation of guitar, bass, and drums. Whether they use a mellotron (an early synthesizer based on tape reels), a Moog (an early electronic keyboard), or actual orchestral instruments, many progressive bands seek a broad aural palette to work from.
Embrace of technology: Many prog groups have shown eagerness to incorporate the technology of their respective eras. The early German prog group Tangerine Dream, for instance, readily embraced synthesizers and helped launch the Krautrock movement.
Close ties to classical music: Prog bands like Emerson, Lake, and Palmer incorporated passages from classical composers like Tchaikovsky into their own music and were broadly inspired by classical composition techniques. Other rock musicians like Frank Zappa wrote chamber music to be performed by classical ensembles.
Concept albums: From Pink Floyd to Yes to Rush, bands of the prog-rock era saw concept albums as a way to match philosophical ambition to their musical prowess.
Literary lyrics: A great deal of progressive rock lyrics draw inspiration from works of literature, poetry, and film. Some prog rock lyricists, like Styx’s Dennis DeYoung, created science fiction scenarios in the lyrics for some of their records.

Not bad, but the concept is still loosey-goosey. Walter Murphy’s “A Fifth of Beethoven” has expanded instrumentation, embrace of technology and close ties to classical music but no one would classify that piece of disco crap as “progressive.” “Well, it’s not rock,” you say. “Tell that to the geniuses who let rappers and hip-hoppers into the Rock ‘n Roll Hall of Fame,” I respond.

Having always found genre definition maddening, I’m going to surrender to default mode in organizing this section: if Wikipedia says it’s progressive, it’s progressive.