Forward-thinking jazz vocalist Kurt Elling follows up his progressive 2011 covers album The Gate with his equally ambitious 2012 release, 1619 Broadway: The Brill Building Project.

Where on his last outing, Elling drew upon an array of musical genres and time periods for his song choices, this time he focuses on the fertile pop songwriting Mecca that was the Brill Building in the '50s and '60s.

The creative epicenter for much of the pop music industry on the East Coast, the Brill Building was the work place for a bevy of legendary artists and songwriters including Carole King, Burt Bacharach and Hal David, and many others.

On The Brill Building Project, Elling picks from a cross-section of these songwriters, running the gamut from such obvious standards as the Sammy Cahn/James Van Heusen-Frank Sinatra vehicle "Come Fly with Me," to more idiosyncratic pop/rock choices like Elling's conceptually arty doo wop-meets-beatnik comedy sketch take on the Coasters' “Shoppin’ for Clothes.” Generally speaking, most of the songs here are reworked by Elling and his band into various contemporary jazz styles that allow Elling plenty of room for his expansive, vocalese-influenced singing style.

He even adds his own dark, socio-satirical point of view to the Monkee's already dark Gerry Goffin and Carole King-penned “Pleasant Valley Sunday,” which recalls the ‘70s jazz-rock of Steely Dan.

A few tracks, such as Duke Ellington's swinging "Tutti for Cootie" and the bluesy 1968 Lou Rawls number "I'm Satisfied," are done in a more straight-ahead, post-bop jazz style.

Others cuts, like the lead-off "On Broadway" and Sam Cooke's "You Send Me," are reimagined as languid, R&B-infused arrangements.

In fact, with his supple, velvet-lined voice, it is perhaps not surprising that it is the more introspective moments like Elling's afterglow ballad version of the Al Dublin/Harry Warren standard “I Only Have Eyes for You” and his atmospheric reworking of Carole King's, “So Far Away” that really stick with you.

Ultimately, though, it is just this diverse stylistic quality, both in the source material and Elling's arrangements, that make The Brill Building Project one of his most interesting albums.