One Direction’s Four Album Will Be One Big 'Musical Rainbow'

1D collaborator reveals each song 'sounds nothing' like the other.

Between "Steal My Girl" and "Fireproof," I have to say that I'm so ready for One Direction's Four album to drop. Only problem is, there's still 47 days to go, but who's counting?

But I do come with some good news, Directioners, because I caught up with Julian Bunetta -- you know, the guy who co-wrote "Steal My Girl," "Best Song Ever" and lots more -- and he told me to expect the unexpected from the band's fourth LP.

"There is probably a whole bunch of stuff in between them ['Steal My Girl' and 'Fireproof'] that sound nothing like each other," Bunetta said. "So it's just one big One Direction musical rainbow; one song is green and one song is blue, one song is red."

And the reason for the array of sounds? Well, that's because Liam, Louis, Harry, Zayn and Niall were all very hands on in the creative process.

"I think most of them were written with the band, either with Louis and Liam or with Harry, and there is a couple of songs that the whole band wrote on at different stages," the songwriter revealed. "So there's five different individuals in this group and they all have five different tastes, so naturally I think the music is going to be pretty diverse because of that."

Bunetta, who said Four features the "best work" he's ever done, also revealed the reason that guys wanted to write about "girls" "love" and "having a really good time." For one, the guys grew up but seconly, the positive response to their last album, Midnight Memories, gave them a big boost of musical confidence.

"I think Midnight Memories was a huge album because they had so much creative input and it worked, and it separated them from the traditional boy band model," Julian said. "No one thought it could get any bigger, but it got so much bigger and I think this really gave them even more artistic confidence that they are more than just a band that was put together on a show ['The X Factor' in the U.K.]. They really deserve what they have and that they are special, talented guys, and I think they are starting to believe that. So going into this album, it was a little different because they had that extra bit of confidence of knowing the process, just internal confidence."