Originally Posted by grindy

Oh boy...
As you might have guessed I'm all about the free jazz, but I do know a bit about the older, less experimental stuff.

Miles Davis - Kind Of Blue
One of the most famous and, as far as I remember, most successful jazz albums. It's considered a masterpiee of modern jazz and I can't imagine any kind of jazz education without it.

Miles Davis - A Tribute To Jack Johnson
Let's stay with Miles here for a second. He made a lot of amazign albums in his fusion phase. Most people would recommend "Bitches Brew", but I'm gonna go with this one since it's shorter and more concise. Soem great jazz-rocking here.

Sonny Rollins - Saxophone Colossus
Great, fun, swinging hard bop album. As you might have guessed it's alla bout the saxophone here, although I also really like the drums here. Soem say Roach's drumming is too heavy-handed here, but screw those people. It's great.

Bill Evans Trio - Waltz For Debby
Beautiful piano trio music. It works well as background easy listening, but it'd be a waste. Wonderful, delicate, but complex playing. Bill Evans is an amazing pianist, but LaFaro's lyrical bass and Motian's mostly brushed drums are equally part of the magic.

Oscar Peterson Trio - Night Train
Another piano trio. Peterson is one of the jazz piano virtuosos. Amazing, groovy stuff. YOu immediately feel cool as hell when putting this one on.

Ornette Coleman - The Shape Of Jazz To Come
This one is regarded as one of the first free jazz albums. Don't let that scare you off. No wild screeching here. It's looser than the albums previously mentioned, but in no way chaotic. Lonely Woman is one of the most gorgeous jazz songs in existence and one of the most played standards. Overall very emotional and vital music on this album.

Eric Dolphy - Out To Lunch
Another free jazz classic whose genre shouldn't scare you off. Weirder than the album above, but so amazingly tight and inventive, you'll be entertained from start to finish.

John Coltrane - A Love Supreme
One of the last more accessible Coltrane albums. Still pretty wild, his sax is amazing and there is some amazing piano playing from McCoy Tyner on that. Rhythm section freaking rocks as well.

Charles Mingus - The Black Saint and the Sinner Lady
A relatively big ensemble plays Mingus's amazing composition. Unique and mindblowing music. Hard to describe it or write about it at all, it has to be experienced.

Art Blakey & The Jazz Messengers - A Night In Tunisia (1961)
Nicely showcasing Blakey's drumming this album has some more conventional pieces, as well as some wilder, almost tribal stuff. Great soloing from all involved.

Gonna take a break now. I'm sure I missed a lot of absolutely essential albums. Also sure Frownland will fill in some of the gaps and possibly contest some of the albums I chose.
So much older stuff I haven't mentioned yet, not to mention newer jazz I haven't covered at all.

Originally Posted by Pet_Sounds

It is 9/8, but it's not counted like a normal 9/8. The whole album uses funky time signatures, hence the title.