Over the course of his first three albums--"The College Dropout" (2004), "Late Registration" (2005) and "Graduation" (2007)--this larger than life son of the city's South Side established himself as one of the most innovative and adventurous forces in hip-hop, with music that has stretched the genre's boundaries further than any mainstream artist since the early '90s, and lyrics that offer a portrait of young African-American manhood which, for all its inconsistencies and flashes of rampant egotism, is as refreshing an alternative to the prevailing gangsta caricature as the one provided by his former neighbor, our President-elect.

West's fourth studio effort originally was intended to follow the progression of life established by its predecessors: After all that schooling, he was set to earn his reward with a disc called "A Good Ass Job." But that album title and, one presumes, the next installment of the hip-pop trajectory of his earlier sounds both were abandoned in favor of an unexpected and utterly unique detour prompted by the painful losses of his mother and his long-time love.

The star's mom, co-manager and mentor Donda West died as a result of complications from cosmetic surgery in November 2007, and Kanye's engagement with Alexis Phifer ended five months later, in April 2008. West already had rapped earnestly and movingly about Donda on "Late Registration," while many of the lyrics on "Graduation" found him bravely questioning his own boastful public persona, admitting the insecurities that it masks and wondering if he is worthy of true love. It's no surprise that he shares even more on the new album, which comes adorned with cover art of a deflated balloon fashioned in the shape of a heart.

West is not always successful in voicing the depths of his pain: The disc ends with a track called "Pinocchio Story" that opens with a paraphrase of the 1961 Elvis Presley hit "(I Can't Help) Falling in Love With You" before shifting into the fashion-plate rapper bemoaning, "There is no Gucci I can buy/There is no Louis Vuitton to put on/There is no finer smell that they could sell/To get my heart out of this hell/Or my mind out of this jail." Ouch.

But the artist can be forgiven this stumble by virtue of the facts that the song is a freestyle rap recorded live onstage in Singapore, and that he turns things around by slowly working an effective if not especially deep literary metaphor: "They always say, 'Kanye, he keeps it real, boy'/Pinocchio's story is, 'I just want to be a real boy'... It's funny: Pinocchio lied, and that's what kept him from it/I tell the truth, and I keep running... There is no Geppetto to guide me, no one right beside me/The only one who was behind me, I can't find her no more."

West is even more eloquent in the preceding track, "Coldest Winter," when he sings, "If spring can take the snow away/Can it melt away all our mistakes/Memories made in the coldest winter/Goodbye my friend/I won't ever love again/Never again."

All of us have felt that way at some point, and as with the great albums cited above, the best moments on "808s & Heartbreak" offer a sense of redemption and uplift via the power of music, though they require fans to set aside almost everything they think they know about the Kanye West sound. Even his familiar and beloved string sections are employed in a very different way here than we've heard on his stellar hits in the past.

In scattered comments to the press and on his blog, West has cited the naked, minimalist vibe of Phil Collins' first solo album "Face Value" (1981) as a big inspiration. (A raw account of his divorce, this was an entirely different Collins than the pandering pop star of "Sussudio" and later hits.) West gets the primal, tom-tom-heavy African drumming right--generated by the Roland TR-808 Rhythm Composer, one of the first programmable drum machines and the source of half the disc's title--but rather than the spare guitar and piano that subtly fleshed out songs such as "In the Air Tonight," the Chicago artist favors more elaborate synth sounds (shades of the Daft Punk electronica of "Stronger") and ubiquitous computer auto-tuning.

The only real rapping on the album comes from brief cameos by guests Young Jeezy and Lil' Wayne; West's vocals are all sung in a flat, Lou Reed- or Bob Dylan-like monotone that shows an almost punk disregard for key or melody. The auto-tune isn't used to improve the quality of his singing (it's doubtful that anything could), but to add a distant, metallic, echoey effect more akin to a vocoder, heightening the sense that this is a man reaching out from the bottom of a deep hole.

The formula is touching and very effective at times, notably on "Say You Will," "Welcome to the Heartbreak," "Coldest Winter" (which builds on the 1983 Tears for Fears song "Memories Fade"), "RoboCop" and "Love Lockdown." But a formula it is, and it wears thin and becomes slightly predictable and repetitive over the course of 12 tracks.

If West had interspersed the more mechanical tracks with some that were the exact opposite--say, simple piano interludes provided by his old collaborators John Legend or Jon Brion--he might have made a masterpiece. Instead, he's merely given us an extremely intriguing, sporadically gripping, undeniably fearless and altogether unexpected piece of his troubled soul.