The band, who gave away their album Radio: ACTIVE free with The Mail On Sunday in 2008, told The Guardian that the music industry has changed in recent years.
Of the decision to give away Radio: ACTIVE, drummer Harry Judd said: "At the time, we were trying to think about how we could do things differently and keep up with the record industry."
Discussing the planned Super City subscription service, available for £6 month, singer Tom Fletcher added: "We're just going to be completely open and show the fans everything. And why not? I think you have to be.
"The music industry is different now. In the olden days, that distance between you and your idols made it special. But now people are craving information, and you have to [provide it]."
He also suggested that he might put up demos of new material on the website before he even plays them to his bandmates and added that fans will have input on single choices and live setlists.
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