One of the reasons Green Day has managed to stay popular for so long is their ability to combine raw punk with commercial pop. The band's experimentation along the way on albums like the rock opera's 'American Idiot' and '21st Century Breakdown'  has allowed them to get outside the limited sound of pure punk.

Lead singer Billie Joe Armstrong says that Green Day is now "going into the unknown" with a trilogy of albums, aptly titled 'Uno!', 'Dos!' and 'Tré!'.  As the material kept flowing in the studio, the band decided to fill three records, with each band member getting their own cover. Armstrong will be on the first, Mike Dirnt on the second and Tre Cool, appropriately, on the third.

'Uno!' will be released on September 25, with 'Dos!' being released shortly thereafter on November 13. The band released the album cover for 'Dos!' and a teaser video this weekend. The trilogy is once again being produced by Rob Cavallo, and the unnamed track on the 'Dos!' teaser video has an almost Georgia Satelites meets punk vibe. Armstrong described the sound differently to Rolling Stone:

"We're changing the guitar sound. We're not going with the big Marshall-amp thing. We wanted something punchier, more power pop – somewhere between AC/DC and the early Beatles."

'Uno!' even has a dance track called "Kill the DJ" that Armstrong compares to the Tom Tom Club's "Genius of Love" or akin to the Clash's 'Sandinista' album. It's Green Day's vison of always looking forward and trying something "dangerous" that keeps the band interesting and relevant. In case you missed it, check out the trailer for 'Uno!' below.