The difference, by ear
Several of these musicians came from prog and brought its technical standard, applying it to four-minute songs instead of suites.
Both are sung cleanly, but progressive rock swings further either way: 60 to 180 bpm against 100 to 130. Songs run longer in progressive rock: usually 6 to 20 minutes, against 3½ to 5 minutes in Arena rock / AOR. To hear the difference, play Journey next to King Crimson. They share a root in rock, and progressive rock came first, by eight years.
In figures
Arena rock / AOR
Where it sits
Rock › Blues rock › Hard rock › Arena rock / AOR
In short
Hard rock polished for stadiums and FM radio: huge choruses, keyboards and glossy production.
How it sounds
- Interlocking keyboards and guitars with choruses harmonised across several voices.
- Glossy production and heavy compression, everything audible on a car radio.
- Structures that are predictable by design: verse, pre-chorus, enormous chorus.
Key acts
- Journey
- Boston
- Foreigner
- Toto
Start here
The pickBoston - More Than a Feeling. Recorded almost entirely in an MIT engineer's basement.
Full page →Progressive rock
Where it sits
In short
Rock with classical ambitions: odd meters, twenty-minute suites, mellotron. The direct foundation of progressive metal.
How it sounds
- Odd meters - 7/8, 5/4, 13/8 - used routinely rather than as an effect.
- Mellotron, Hammond organ, Moog and later polyphonic synthesizers.
- Long suites, concept albums, sometimes a single piece per side of vinyl.
Key acts
- King Crimson
- Yes
- Genesis
- Rush
Start here
The pickKing Crimson - In the Court of the Crimson King. The first track tells you everything.
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