The upcoming Prince Sign O' the Times box set is going to be incredible - but not quite complete.

Forty-five previously unreleased tracks will make their debut on the long-awaited expanded edition of Prince's boundary-obliterating 1987 double album. But several tracks have been left off that would have helped create a more complete retelling of one of his most creative periods.

In an attempt to avoid including songs that have appeared on other official Prince releases, titles slated for inclusion on Sign O' the Times precursors such as Dream Factory, Camille and the original version of Crystal Ball have been left off the new collection.

Songs like "Dream Factory, "Last Heart," "Movie Star," "Sexual Suicide" and the full-length, 10-minute-plus version of "Crystal Ball" were recorded for possible inclusion on a proposed album named Dream Factory, which was to be Prince and the Revolution's follow-up to 1986's Parade. All five tracks were instead included on 1998's vault-excavating collection Crystal Ball. A 7" edit of "Crystal Ball" will appear on the new Sign O' the Times box.

Hear Prince's 'Last Heart'

After the breakup of the Revolution, Prince abandoned the Dream Factory project and briefly focused on Camille, an album that found him exploring a new alter ego with the help of pitch-shifted vocals.

Three songs from these sessions are absent from the Sign O' the Times box set: "Feel U Up" was released as the B-side to 1989's "Partyman" single; "Good Love" was released on the soundtrack to 1988's Bright Lights, Big City and on the 1998 version of Crystal Ball; and "Rockhard in a Funky Place" can be found on The Black Album, which was slated to be Prince's 1988 dance-floor-focused follow-up to Sign O' the Times, but was shelved until 1994.

Camille was soon put aside as well, in favor of a triple-disc project named Crystal Ball, which would feature songs from both the Dream Factory and Camille sessions. In addition to "Good Love" and "Rockhard in a Funky Place," the album was supposed to include "Joy in Repetition," which instead made its debut on 1990's Graffiti Bridge.

Prince’s record label ultimately balked at the idea of releasing a triple album, and the Crystal Ball tracks were boiled down to the double-disc Sign O’ the Times instead. Two decades later, Prince repurposed the Crystal Ball title for a 1998 compilation of rare and unreleased tracks that spanned his career.

Fans can recreating the Dream Factory, Camille and Crystal Ball albums by combining new tracks from the Sign O' the Times box with the nine previously released sessions songs, but it would be nice to have them all together in one collection, mixed and mastered to consistent audio standards. Who knows? Maybe some day all three albums will finally be assembled and released on their own?


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