Most astonishing two-album runs in the history of rock music

Van Morrison - Astral Weeks (1968) and Moondance (1970)

Morrison had previously been a pop singer with songs such as "Brown Eyed Girl" which was a fine piece of music, but art it was not. Instead, the performer remade himself on Astral Weeks by blending blues, folk, and jazz into something that seemed as if it might have come from California but was sifted through a fuse box of Belfast. We were treated to tunes such as "Sweet Thing."

Less experimental but almost more sure, Moondance churned out winners like "Into the Mystic." The song is perhaps the best example of how Morrison could take a simple melody and work his magic and make one have a nearly spiritual experience.

The record is more soulful than its predecessor and that was by intent. "And It Stoned Me" could never have been a folk song, but feels so much more timeless because of its implied hearkening to Motown.

Prince - 1999 (1982) and Purple Rain (1984)

Prior to 1999, Prince had released four studio albums. His previous two, Dirty Mind and Controversy, were well-received by critics but Prince had not yet earned a lot of commercial success. That would all change with this record. The first three songs - they made up the entire first side of the double LP - were all ridiculously good and worthy of being many artists' best track ever: "1999," "Little Red Corvette," and "Delirious."

Like much of Prince's previous work, some of the songs did stray into being overly sexual, but he also tempered those with more artistic songs such as "All the Critics Love You in New York." The album went platinum four times in the United States upon release.

This record set the tone for the iconic Purple Rain, which was also the soundtrack to the movie of the same name. The album would make Prince into an international superstar on the same level as Michael Jackson at the time. Purple Rain went platinum 13 times upon its initial release.

The record was completely worth it as well. From the intro "Let's Go Crazy," which showcased Prince's gift as a guitar god, to the unimaginably catchy "I Would Die 4 U" to literally one of the best songs ever created, "Purple Rain."

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