R.

When it was released in 1998, R. Kelly’s R. was the Chicago singer/writer/producer’s magnum opus: a sprawling 29-song album that testified to his creativity, productivity, and range. It was the era of the hip-hop double album, and this mammoth release helped confirm that Kelly saw his brand of R&B firmly in the context of rap music. Here, he works with some of the best in the game, from Jay-Z and Nas to Chicago’s own Crucial Conflict. Even when he wasn't specifically making rap songs, Kelly was perhaps the first R&B singer who felt wholly of that world. R. is everything a double album should be, in that it has a little of everything: the outlandish concepts behind “The Opera” and “2nd Kelly,” the darkened pleas of “Don’t Put Me Out” and “Suicide,” and the inspirational balladry of “I’m Your Angel.” That R. features appearances from both Celine Dion and the unhinged Queens emcee Noreaga speaks to the range of Kelly’s reach. While “I Believe I Can Fly” became a universal song in the tradition of Michael Jackson, the album’s shadowy heart resides in the timeless cloaked R&B of “Half on a Baby,” “When a Woman’s Fed Up," and “Down Low Double Life.”