This post was inspired by the utterly ridiculous post in Loudwire who played off the Big 4 of thrash by revealing thier picks for the Big 4 of other genres. In some cases they nailed it...in some they failed miserably. Can I do better? Maybe, maybe not but I'm sure as hell gonna give it my best shot.
Big 4 of Prog Rock:
Rush
Yes
Emerson, Lake & Palmer
Kansas
Big 4 of Southern Rock
Lynyrd Skynyrd
Allman Brother
Molly Hatchet
ZZ Top
Big 4 of Power Metal
Blind Guardian
Helloween
Gamma Ray
Stratovarius
Big 4 of Doom
Black Sabbath
Candlemass
Trouble
Katatonia
Big 4 of Prog Metal
Dream Theater
Fates Warning
Opeth
Queensryche
More to Come