Trying to whittle Isaac Hayes' mammoth output over 30 years down to a manageable single disc is a futile task. Not only is there so much material, but many of his best tracks, at least from the Stax years, are over ten minutes long. As much as this disc gives it a valiant shot, it's doomed by time constraints alone. Since the majority of Hayes' most memorable work after his non-performing, songwriting years was during the '70s, this collection nabs 13 of its 16 tracks from that decade and should probably have focused entirely on that period. The two later cuts that close the disc -- especially the meandering "Ike's Rap" from 1986 -- are disposable. More problematic, though, is the surreptitious editing of Hayes' longer material like "Never Can Say Goodbye," "Walk on By," and "Joy" (although interestingly not the nine-minute "Hyperbol"), which are all severely shortened from their original versions. Unfortunately, that essential information is nowhere to be found on the outside sleeve or liner notes. That said, the meat of those extended songs is still represented in the edits, and Hayes' trademarked slow-burn soul/funk permeates the bulk of this collection. The decision to eliminate most of his soundtrack work -- save for two tracks from Shaft -- was a smart one, and except for the cliché disco of "Don't Let Go" and the up-beat rubber band groove of "Out of the Ghetto," the album sticks primarily to the unhurried gooey funk formula that made Hayes' name synonymous with low lights, between-the-sheets, sweet, sizzling lovin'. Aside from the questionable choice of the loungy "It's Heaven to Me," where Hayes sounds like a soulful Engelbert Humperdinck, the disc does an admirable job of selecting its tracks. The duet with Barry White -- nicked from White's obscure 1991 Put Me in Your Mix disc -- finds the two love men going head to head with surprisingly effective results. Not as good as it could have been even with the single-disc restrictions, Ultimate Collection is a reasonable place to start, but falls short of providing a well-rounded look at the legendary musician.