Harry Nilsson's relatively short life was messy, complicated and not easily explained in a sentence or two. Likewise, his music was just as scattered, unfocused and undefinable.

It makes boxing up his career a tough and possibly futile task. Which is why, even at 17 discs, 'The RCA Albums Collection' can't really pinpoint the restless artist. Nothing can, really. But this massive set makes a valiant effort.

Collecting Nilsson's 14 albums on the label -- from 1967's 'Pandemonium Shadow Show' to 1977's 'Knnillssonn' -- along with three discs of session outtakes, alternate versions and foreign-language tracks, 'The RCA Albums Collection' gathers pretty much everything the singer-songwriter recorded for the company -- he cut a few early singles and later songs, but his best work was for RCA -- including terrific records like 1970's 'Nilsson Sings Newman' (made with Randy Newman, before either artist firmly established himself), 1971's commercial breakthrough 'Nilsson Schmilsson' and 1973's 'A Little Touch of Schmilsson in the Night,' a collection of standards Rod Stewart wouldn't get his hands on until decades later.

And from the start, Nilsson was a complex artist. His first few albums veer from paisley pop to ambling folk to Beatles covers (even though he made his rep as a songwriter penning songs like 'One,' a hit for Three Dog Night, Nilsson's two biggest hits were written by someone else). He even released a remix album decades before anyone else thought of it. But he began to find focus as the '60s turned to the '70s, and his best album, 'Nilsson Schmilsson,' was a Top 10 hit that included his only No. 1, a cover of Badfinger's 'Without You.' The rest of the album is just as good, mixing everything from sturdy rockers ('Jump Into the Fire') to playful pop ('Coconut').

The next five years of Nilsson's decade-long stay at RCA were occupied by a 'Schmilsson' sequel, the standards album, a sloppy but endearing collaboration with drinking buddy John Lennon and four little-heard and spotty LPs that pretty much ended his career (Nilsson despised performing live and gave up recording albums after a 1980 outing that was never even released in the U.S.).

The Brooklyn-born Nilsson died in 1994 at the age of 52 of a heart attack. But he kept plenty busy during the 10-year span 'The RCA Albums Collection' covers. In addition to the bonus tracks that round out each individual album, three discs of 'Sessions' pretty much compile every note Nilsson released. From demos of '1941' and 'Coconut' to alternate takes of 'One' and 'Rainmaker' to previously unreleased cuts like 'The Family' and 'Marry Me a Little' (all excellent), these leftovers help to fill in the gaps along the way. With the hundreds of songs collected on this monumental box, they go a long way in helping to explain a flawed but fascinating artist, even if he could never really be contained.


More From Ultimate Classic Rock