'The Joshua Tree' re-release: details of new tracks revealed

The remastered version of the album features several unreleased demos from The Joshua Tree sessions. Bono recently added new vocals to one of them, 'Wave of Sorrow’, and this week talked about the inspiration for the song on the band's official website.

Interviewed in New York, he explained that 'Wave of Sorrow' "...was one of the songs from the Joshua Tree sessions that we never finished… a song that was trying to describe experiences that myself and Ali had when we were working in Ethiopia during the famine."

As well as a fourteen track bonus-CD of B-sides and rarities, the 2007 release of the classic album features a live concert DVD from Paris in 1987, liner notes from band and producers and previously unseen photos in a limited edition booklet.