A few of my favourites from 1973:
Steely Dan - Countdown to Ecstasy
Roxy Music - For Your Pleasure / Stranded
Rick Wakeman - The Six Wives of Henry VIII
The Isley Brothers - 3 + 3
Judee Sill - Heart Food
Gentle Giant - In A Glass House
Doobie Brothers - The Captain & Me
Gong - Flying Teapot...
I can make a pretty decent case for 1969 ...
The Beatles - Abbey Road
Led Zeppelin 1 & II
King Crimson - In The Court of the Crimson King
Velvet Underground - Velvet Underground
The Stooges - The Stooges
The Rolling Stones - Let It Bleed
Nick Drake - Five Leaves Left
Frank Zappa - Hot Rats
Neil...