Talib Kweli and Hi-Tek Reflection Eternal -- rapper Talib Kweli and producer Hi-Tek -- have pushed back the release of their sophomore album, 'Revolutions Per Minute.' The long-awaited follow-up to their 2000 debut, Train of Thought,' will now hit stores on April 20, two weeks after the original street date of April 6.

Following the overwhelming critical success of 'Train of Thought,' fans clamored for a new album as the pair went their separate ways professionally. Kweli released a trio of albums starting with 2002's 'Quality,' which Hi-Tek matched with his own 'Hi-Teknology,' 'Hi-Teknology 2: The Chip,' and 'Hi-Teknology 3: Underground,' in addition to working as an in-house producer with Dr. Dre's Aftermath Entertainment. 'Revolutions Per Minute' represents eight years of independent growth and has already received favorable reviews, including a four and half mic rating from The Source magazine.

To his Twitter followers, Kweli announced, "Every all 126K of you buy 'Revolutions Per Minute' the week of April 20th, you will guarantee a Number 1 record for Reflection Eternal ... " 'The RE:Union' mixtape, featuring the duo's classics as well as new tracks like the 'Just Begun' collaboration with Mos Def, Jay Electronica, and Roc Nation signee J. Cole, provides a taste of what the full-length will offer, and is available for free download now at YearOfTheBlacksmith.com.

'Revolutions Per Minute''s lead single 'Back Again' is currently on iTunes, with 'In This World' available on March 23 following its video premiere Sunday, March 7 on MySpace music. A preview for the video can be seen after the jump.

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