PHILIDELPHIA: the city of brotherly love, the Liberty Bell, soft cheese and soul music.

Now the cradle of American independence gives us another cause to celebrate – in the shape of a hip-hop duo who are mixing up the gritty sound of the streets with feelgood dance beats.

They are rapper Chidera ‘Chiddy’ Anamege, left, and production master Xaphoon Jones, right.

Trading under the name Chiddy Bang, Chiddy and Xaphoon (real name Noah Beresin) are already rewriting the hip-hop rule book – chucking out all those polished beats and that ridiculous posturing, and bringing in a funky, indie vibe – sampling everything from Gorillaz and Hot Chip to Ellie Goulding and grime artist Tinie Tempah. Even Radiohead gets the Chiddy Bang treatment (Because) – which, I suspect they are quite proud of.

“In the early days of Chiddy Bang, we sat down and tried to figure out what kind of music we were making,” says multi-instrumentalist and self-confessed “sample-fiend” Xaphoon, 19, who perfected his craft, like millions of other technical wizards, in his bedroom.

“Is it rap? Collage music? Is it this? Is it that? But then we decided sitting around trying to classify the music and being like a pretentious hipster was pointless. We didn’t need any rules – we just needed ‘dope’ beats. That’s our motto.”

The pair met at Philly’s Drexel University in 2008 where Xaphoon was fast becoming a legend in the studio, inspired by a broad palette of genres – from punk and hardcore to jazz and rap.

“Xaphoon’s production is unique,” says Chiddy, 19. “When people hear it, they ‘bug out’. They ask him how he did it, what equipment he used. They interrogate him; it happens all the time.”

Chiddy, who grew up in Newark, New Jersey, with his Nigerian family, has a more straightforward talent – he’s an unbelievable rapper.

“That’s what people would do at school – rap,” he recalls. “Everybody was rapping at recess. All my boys would call each other and rap to each other over the phone for hours. I knew I could do it better than most kids my age. I always had faith in myself. I knew that I’d make it, it was only a matter of time.”

Xaphoon agrees: “Chiddy rhymes like a chess player, in the sense that he sings the words now but he’s thinking about the next couple of bars.

“I’ve produced a lot of rappers working in studios in Philly and he is, hands down, the best freestyler I’ve ever met.”

Their first release, mixtape The Swelly Express, was a self-released autobiographical concept album, which tells the story of their trips to New York to be courted by the major labels. Since its release in October, it has been downloaded 100,000 times.

And it reached the ears of hip-hop royalty, with Kanye, Kid Cudi and Snoop Dogg all self-proclaimed fans.

But the pair remain grounded. “The Swelly Express was a journey – it was about us trying to break down doors but that’s done now,” says Chiddy.

As he says, it’s time to move on. And we can expect to hear a lot more from this Philly pair in the next few months.

* Chiddy Bang play the Oxford O2 Academy on Friday. New single Truth, sampling Passion Pit’s Better Things is out next week.