When the quiet half of Arizona indie-pop duo The Format, multi-instrumentalist Sam Means, decided to leave the touring life, his band’s fan base was crestfallen. But Format’s lead singer Nate Ruess pressed on, recruiting Andrew Dost and Jack Antonoff for Fun, who released their debut album “Aim and Ignite” in August of 2009.

Fun’s sound, still driven by Ruess’ straightforward lyricism and powerful, expressive tenor, is both a continuation of The Format’s grandiose pop compositions and an expansion.

“We all, at the time [we made the album] and maybe still, adhere to the concept of ‘anything worth doing is worth overdoing,’” Ruess says.

Whereas The Format experimented with chamber pop and brass bands, Fun is even bigger, referencing gospel, arena rock and even the epic-ness of Broadway.

“I really enjoy that at this point in my life because very few things are off limits,” Ruess says. “And very few things are impossible to do.”