Fitz and the Tantrums

Fitz and the Tantrums headline Rams Head Live this weekend. (Handout / April 9, 2013)

It took Michael Fitzpatrick, the 42-year-old lead singer of Fitz and the Tantrums, many years of toiling as a self-taught studio engineer and aspiring musician in Los Angeles to find the success he craved.

When it finally came, courtesy of his sextet's breakthrough 2010 debut album "Pickin' Up the Pieces," Fitzpatrick knew it could be his only shot, so he and his band refused to turn down any opportunity to gain new fans. Whether it was a late-night talk show performance or a festival gig, Fitz and the Tantrums were there, playing its soulful, guitar-less take on indie-pop.

"As a band starting out, it's so hard to break through the mire, you know?" said Fitzpatrick, whose band headlines Rams Head Live on Sunday. "You don't have the liberty to say no. That was our rule: We said no to nothing in almost three-and-a-half years of pushing the band."

With last month's release of "More Than Just a Dream," the band's second album, Fitz and the Tantrums are still pushing, but in new ways. They brought in veteran producer Tony Hoffer (Beck, M83) to blend synthetic sounds with the band's bombastic live instrumentation. There's even guitar on this record because, according to Fitzpatrick, "everything was on the table."

One of the major goals of "Dream" was to shed the band's "retro" label, which quickly came with the success of "Moneygrabber," the driving hit single from "Pieces."

"It felt dismissive or too easy," Fitzpatrick said of the "retro" tag.

In the process of losing the label, the sextet pushed its sound even further outside of easy categorization, he says.

"We just wanted to be more bold and brazen in that attempt to create those cross-genre moments, and really kind of define ourselves even further," Fitzpatrick said.

The sophomore album still sounds like Fitz and the Tantrums, but with grander ambitions. There are elements of '60s soul, '80s British Invasion new wave, indie-rock and hip-hop throughout the album's 12 tracks. In almost every case, "Dream" sounds bigger than its predecessor, which seems appropriate for a band whose profile and stages have grown as well.

What hasn't changed is the chemistry between Fitzpatrick and co-vocalist Noelle Scaggs, which he says was apparent from his first rehearsal with the 33-year-old female singer. Their voices blend together smoothly, he says, but the duo's dynamic is built on something stronger than mere notes and phrases.

"Because we're such fierce performers, we kept pushing each other to do more — dance harder, engage more with the audience," Fitzpatrick said. "It really created this healthy competition to push ourselves constantly, further and further."

Fitzpatrick talks about "pushing forward" multiple times during our 20-minute conversation, to the point where it seems to be the main thing fueling his creativity. He talks happily about the reaction the new album has received from fans and that the lead single, "Out of My League," is finding its footing on the radio. But for someone who spent a long time trying to find national success as a songwriter and performer, Fitzpatrick seems acutely aware that satisfaction can quickly turn into complacency.

"You can always want more," he said. "That's what I've learned from success: You can always be dissatisfied with where you are."

If you go

Fitz and the Tantrums perform Sunday at Rams Head Live, 20 Market Place in Power Plant Live. Doors open at 7 p.m. Saints of Valory and Ivy Levan will also perform. Tickets are $25. Call 410-244-1131 or go to ramsheadlive.com.