This summer, the record industry stumbled. Despite plugging many of the holes in the dam separating music from Internet users, U.S. album sales hit historic lows

In hip-hop, several rappers—Kanye, Big Sean, 2 Chainz, Mac Miller—saw sales from their most recent record fail to match the one before it. Even Drake only managed to push his first-week total up slightly over his last, suggesting he might have already plateaued

Of course, the underground still produced thousands of mixtapes, uploaded to DatPiff, LiveMixtapes (and Indy.Livemixtapes), HotNewHipHop, Soundcloud, and Bandcamp. Promising new artists arrived, as did hundreds of retreads and unmemorable, bland trend-chasers.

Hopefully, this column will help draw attention to the songs that are worth your time, regardless of positioning or pedigree. So let's take a look at September's #DeepCuts: The Mixtape Tracks You're Sleeping On.

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