Bruno Mars: Penning tunes is tough

Bruno Mars says writing a "big" song is one of the "hardest things to do".

The singer hit the music scene with his first album Doo-Wops & Hooligans in 2010 and recently released Unorthodox Jukebox, which spawned smash-hit Locked Out of Heaven.

His tracks often have sexual connotations and daring lyrics, but Bruno is proud he treads a fine line with his music as he believes that takes guts.

"You know how hard it is to write a big song? That sh*t is hard, man. It's so hard to do. Might be one of the hardest things to ever do," he argued in an interview with GQ.

"I don't ever want to come out with something safe and get away with, 'It sounds good!' It's got to be more than sounding good."

His latest album includes track Gorilla, which comes complete with explicit lyrics.

The singer is happy to "shock", calling the song "awesome" and drawing on his own favourite tunes.

"The music I like are events. F**king Bohemian Rhapsody is my favourite song - that song's an event. And that's what I want to do. I'm sure that shocked the world, that song. Billie Jean [by Michael Jackson] shocked the world," he listed.

"Smells Like Teen Spirit. Those songs are events. That guy [Kurt Cobain] put everything he got into that, and he meant it. It's that unexplainable high. Why I keep doing it. That feeling that you keep on chasing and chasing. Because it's nothing, man. It's taking the air and turning it into something. That's the feeling."

Locked Out of Heaven also references sex, while 2010 hit Grenade lists the harm Bruno would be prepared to do to himself for his love, despite the feeling being unrequited.

While he doesn't mind shocking his audience, the 27-year-old hopes fans will also see the beauty in his music.

"If you think it's blasphemous, then obviously you don't know that it's poetry. You can pick apart all of my songs. 'A bullet through your brain,' man? That's not politically correct," he vented.

"You're not listening to it right if you're picking it apart like that. You know? I can't over-think everything I wrote or worry about that kind of stuff. Hopefully people should know. There's no blasphemy. Or insult to any religion. It's just f**king poetry, whether you believe me or not."

While Bruno is very animated about his songs, he also takes a moment to reflect on his success and the fickle nature of fame.

In 2010 the star was arrested in Las Vegas for drug possession, which gave him pause for thought.

"'I can take this sh*it away from you, young man.' That was the lesson. You've slaved away for years and years and years. You've prepped your whole life. It's all you know how to do. You're a kid experiencing life in f**king Sin City, and that was the lesson: it can all be taken away. Put you in a weird place. Embarrass you," he said.