Gabe Simon is riding high as a member of one of the summer’s breakout acts, but right now, he’s sitting in a smelly van motoring toward Northampton, Mass., and all he’s thinking about is what he’s going to do when he gets to the Holy City.

“I can’t wait to get to Charleston, kick my shoes off, wade onto the beach, and have a good time,” says the Kopecky Family Band singer/guitarist and Greenville, S.C. native. “I had a bunch of friends growing up that were always going down” to Charleston.

Six years ago, Simon left South Carolina to study music at Belmont University in Nashville, where he met Kelsey Kopecky. The chemistry was immediate and the songs came quick. Together, their music mixed ’60s psych, shambling folk, roots rock, and adult pop fueled by rich harmonies and the boy-girl vocal interplay of Simon and Kopecky. Within a couple months the pair had recruited four bandmates to join them and started playing around the region.

“We toured every weekend while we were in college,” Simon says. “Kelsey says we really became a family in that and the name took on a whole new meaning.”

Since forming in 2007, Simon and the gang have recorded three EPs — 2008’s Embrace, and 2010’s The Disaster and Of Epic Proportions — and in October of last year self-released Kids Raising Kids. Several months after Kids‘ hit the racks, they signed with ATO. The label re-released the album in April and gave it the push necessary to propel the single “Heartbeat” to No. 8 on Billboard’s Triple A chart in June. Late night television and festival appearances ensued all summer. Their breakout is all the stranger because the Kopecky Family Band were co-headliners with the Lumineers last spring, just as that band blew up on the strength of “Ho Hey.”

“It’s bizarre to see new bands blow up and now to be one of those bands. We’re all taking everything with a grain of salt every time, but your song pops up on the radio and we’re still blown away,” says Simon, who fondly recalls the terror of appearing on The Tonight Show. Not only was he shaking in his boots but, Simon says, he was “having hair and makeup people drying my armpits with hair dryers because I was so nervous.”

A lot of the band’s appeal lies in their dynamism and vibrancy. Having six players allows them to marshal a wealth of sound. Since everyone’s fluent in multiple instruments, they’re often switching things up. It results in songs with plenty of character. “The biggest thing we learned early on was when not to play,” Simon says. “Everyone can make a lot of noise, so when you choose to play, you make every note count, and that’s kind of been our mantra.”

The band’s willingness to subjugate its individual members’ talents to the song produces spacious numbers with loose, unhurried grace. “Are You Listening” glides through spooky late-night shimmer behind a rubbery guitar riff and light keyboard washes, with a whistled bridge that subtly evokes the dreamy sway of Peter Bjorn and John’s “Young Folks.” “Hope” possesses orch-pop flourishes (credit cellist Markus Midkiff) and a delicate beauty, but it blooms into an upbeat, well-crafted number worthy of the New Pornographers. Simon and company embrace the eclecticism.

“You [can] go from a song like ‘Hope’ or ‘Are You Listening,’ which has everyone singing and yet is completely stripped down to the opposite side of the spectrum,” Simon says, noting the frenetic activity in tracks such as “My Way.” “Steven [Holmes is] playing drum and guitar, Kelsey’s playing bass, and our other guitarist is playing guitar and horns. Our cellist is running around playing keys, cello, glockenspiel, more guitar, and tambourines while singing, and our drummer’s carrying through it all.”

The flexibility of the Kopecky Family Band’s sound and its utter infectiousness have afforded the group the opportunity to play with a range of acts — the Lumineers, the Mowglis, Michael Franti and Spearhead. “We want to be known as the band that can play with anybody,” he says. “We want to be that band that people take out because we have fun with everybody, we get the crowd engaged, and we’re a fun band to work with.”

So far so good. The Kopecky Family Band has tours scheduled through the end of the year and hopes are the group will make their first trip to Europe within the first few months of the new year. As the songs comprising Kids Raising Kids are at least two years old, the act has built up a backlog of new material. The band even begun cutting tracks, both on the road and in the outfit’s Nashville hometown.

“The six of us in this band are definitely not the best six players we know in any capacity,” Simon says. “We put our hearts into it, but we got where we are because we work hard and we believe in our music. And we believe in one another. We aren’t the hired guns that play on all the John Mayer records.”