Number 1 is Number 1, but anything after is just kind of in there somewhere, in whatever order I remember them.
#1 - MONO - Hymn to the Immortal Wind Oh good Lord this album is PERFECT. I'm a huge fan of instrumental music, and this is the kingpin. Not only is the music astoundingly beautiful, but the art that goes along with it is fantastic and the story written alongside perfectly puts the album into words. It's the perfect combination of the three main art-forms.
Arcade Fire - The Suburbs This album is a grand, slightly dark piece that really encapsulates the feeling of a suburban raising, and I love it.
The Who - Quadrophenia The Who did some awesome, solid rock before this, but this album is a huge cohesive monster with an atmosphere that no album has replicated since.
The Beatles - Sgt. Pepper's Lonely Hearts Club Band There were good albums before this, but this was the first GREAT album. It's just great all the way through, and the fact that no other albums might have existed without this album helps as well.
Explosions in the Sky - All of a Sudden I Miss Everyone I can't even explain it, I just love it.
Godspeed You! Black Emperor - Lift Your Skinny Fists Like Antennas to Heaven Simple GEN!US.
Neutral Milk Hotel - In the Aeroplane Over the Sea If anything can be said about this album it's that it's simply interesting. It has great instrumentation and the lyrics are astoundingly cryptic and strange, but it just paints this big, beautiful picture and creates its own world. I doubt there will ever be an album like this again.
The Allman Brothers' Band - Eat a Peach There's something magical about this album. This list is filled with big, loud, serious albums, but this album just reminds me that sometimes simpler is better. You can tell the band had fun with this one, and the final track is among my favorite songs ever, for reasons I may post about at a later date.
Fleet Foxes - Helplessness Blues I just love this album, it's full of interesting rhythm and mature lyrics, plus a fair bit of experimentation that really sets them ahead of their contemporaries (i.e. The Shrine/ An Argument).
Explosions in the Sky - The Rescue EitS is my favorite band, so it makes sense that they're the only band with two albums on the list, but this last one isn't an album, it's an EP. This piece was spontaneously written and recorded in eight days, and the short incubation period somehow resulted in some really great stuff. Just by chance they came up with some of their best almost on the spot, with highlights being tracks five and six. Really this album is just casual.
Honorable mentions:
Bon Iver - Bon Iver
Pink Floyd - Animals
Arcade Fire - Funeral
The National - High Violet
Zammuto - Zammuto
This Will Destroy you - Young Mountain
The Beatles - Abbey Road
RadioHead - Ok Computer