Quite a few already mentioned but…
Pink Floyd (of course
) - DSotM, WYWH, PatGoD, Animals & The Wall
David Bowie - The Rise and Fall of Ziggy Stardust and The Spiders From Mars
Fleetwood Mac - Rumours
Led Zeppelin - Led Zeppelin II
Frank Zappa - Apostrophe (')
Bob Dylan - Highway 61
The Rolling Stones - Let It Bleed
Captain Beefheart And His Magic Band - Trout Mask Replica
The Who - Who’s Next
Anathema - Judgement
ELP - Tarkus
King Crimson - In the Court of the Crimson King
Tangerine Dream - Zeit
Muse - Black Holes and Revelations
The Beatles - Revolver
Syd Barrett - The Madcap Laughs
Opeth - Blackwater Park
Kate Bush - Hounds of Love
Radiohead - OK Computer
Steven Wilson - HAND. CANNOT. ERASE.
Tool - Ænima
Deep Purple - Machine Head
Fairport Convention - Liege And Lief
Neil Young - Harvest
Cream - Disraeli Gears
Crosby, Stills, Nash & Young - Déjà Vu
Rush - Fly By Night
Joni Mitchell - Blue
Black Sabbath - Paranoid
Sigur Rós - Takk…
The Moody Blues - Days of Future Passed
The Small Faces - Ogden’s Nut Gone Flake
Jethro Tull - Stand Up
I could go on…however I’ll finish with any of Nick Drake’s albums and I’m a big Porcupine Tree fan so… Stupid Dream, FoaBP, Deadwing & In Absentia would all be high up there