Featuring never before heard instrumentals, as well as covers of Stevie Wonder and Band of Gypsies classics.

Following quick on the heels of its first-ever vinyl release, The J.B.'s demo for James Brown is now available to stream.

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Unearthed and pressed by the good folks at Now-Again Records as a Record Store Day exclusive, the mythical three-track set compiles "Mess on My Thing" -- a raw, once-thought lost, demo recorded by the group (led by a barely 18-year-old Bootsy Collins) for Brown at King Studios in 1969 -- as well as the previously unreleased instrumental "The Wedge," and the complete 22-minute version of "When You Feel It, Grunt If You Can," which features interpolations of Stevie Wonder's "I Was Made to Love Her" and Band of Gypsies' "Power of Soul." And now it's making a digital debut.

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You can hear the J.B.'s demo that brought the group under James Brown's wing below. Head over to Rappcats to pick up your copy on vinyl.