1973
Aerosmith - Aerosmith
Alice Cooper - Billion Dollar Babies/Muscle of Love
Black Sabbath - Sabbath Bloody Sabbath
Blue Oyster Cult - Tyranny and Mutation
Budgie - Never Turn Your Back On a Friend
Deep Purple - Who Do We Think We Are
Genesis - Selling England By the Pound
King Crimson - Larks' Tongues in Aspic
Led Zeppelin - Houses of the Holy
Mahavishnu Orchestra - Birds of Fire
Montrose - Montrose
Queen - Queen
Thin Lizzy - Vagabonds of the Western World
Uriah Heep - Sweet Freedom
1973 is an interesting year. We've got some bands with their very first albums, some bands with albums that would be the last before a hiatus, lineup change, or change in sound altogether, and we also have a couple bands who have reemerged with a brand new sound.
First we have the debuts. Some big first albums here. Aerosmith, Queen, and Montrose would go on to become big influences on the Rock and Metal scenes. The Queen album in particular is very heavy, there's definitely a Metal influence in there. Montrose marks the recorded debut of Sammy Hagar, who would go on to bigger things later, but definitely had the edge and grit of a Metal singer. Aerosmith, on the other hand, definitely isn't Metal but they did pave the way for the more Blues based American bands, particularly in Glam Metal.
In the next category we have Alice Cooper and Deep Purple. Muscle of Love and Who Do We Think We Are would go on to be the last albums of the bands' original and classic lineups respectively. Both are sort of viewed as weak points in their careers, although Woman From Tokyo is a popular tune. And on the Alice Cooper front, they also released the future classic Billion Dollar Babies earlier this year.
Finally, we've got some comeback albums and overhauls of previous sounds. Led Zeppelin is the big one here, who released what is easily their most diverse album. The blues based hard rock really takes a back seat here in favor of folk, reggae, and even Indian music. It's even less of a Metal album than IV, but I think a lot of Metal groups today who embrace diverse influences likely got that from Zeppelin. We also have King Crimson with a brand new lineup and a totally different sound with their landmark Larks' Tongues in Aspic. This string of albums by Crimson contains easily their heaviest material, where in some ways they invented the progressive metal genre. I have a hard time listening to King Crimson and not thinking that they're pretty much directly responsible for bands like Tool, Meshuggah, and even the heavier side of Dream Theater.
As for everything else, the big eyebrow raiser is probably going to be Mahavishnu Orchestra. I included their album because it's probably the closest Jazz ever got to Metal. This album was seriously heavy stuff and Mahavishnu often toured with Hard Rock bands rather than Jazz groups. McLaughlin has a guitar style that's aggressive, frantic, and he seriously shreds. Dare I say he almost reminds me of Janick Gers? There's also one more Genesis album, mostly included for Dancing With the Moonlit Knight and it's Maiden-esque gallop. The rest of the bands included are pretty much continuing what they've been doing.
Also noteworthy is that this is the year Halford joins Judas Priest. They're coming soon!