According to a posting at Toolband.com, TOOL's brand-new album was mastered on Tuesday, January 31 at Gateway Mastering Studios in Portland, Maine by Bob Ludwig. The members of the band were present during the mastering, according to a posting on the site.TOOL's first CD since 2001's "Lateralus" is tentatively scheduled for release in late April or early May. A video directed by guitarist Adam Jones is also said to be in the works, with members of the band preparing to embark on an an international press tour for the new effort. Photos taken during the recording of the LP, which were posted on Jones' online blog, showed that QUEENS OF THE STONE AGE's Josh Homme, MELVINS guitarist King Buzzo and ISIS frontman Aaron Turner had stopped into the studio during the sessions. It's not yet known whether the guests will appear on the album. As previously reported, TOOL have been confirmed for the seventh edition of the Coachella Valley Music & Arts Festival, which will take over the small desert town of Indio, California on April 29 and 30. The band are one of the first acts to be confirmed for this year's Roskilde Festival, set to take place June 29 – July 2 in Roskilde, Denmark. It was also reported by Norwegian national TV channel TV2 that TOOL will play Norway's Quart festival in early July. Both the Roskilde and Quart performances are likely to be part of a European festival tour in the summer.