FOUR years ago folk rockers the Lumineers enjoyed a hugely successful debut album.

For the follow-up, they wanted to get even more emotional than before.

And singer Wes Schultz reckons that’s exactly what they’ve managed on Cleopatra, which they bring to the Barrowland tonight.

“On the first record, I think we were full of an innocence and an enthusiasm that had less time for subtlety,” he says.

“On this second album we aimed to create an emotional arc to it... I think like a lot of writers, not isolated to music, I look for a story that is compelling and someone whose story does not follow a straight line, someone with beautiful contradictions. It is these contradictions that make the character real and believable.”

There is plenty of evidence of that approach on Cleopatra, which was released earlier this week. The title track is inspired by a taxi driver the Denver band encountered while on tour in Eastern European country Georgia, while other songs look at family members, including Wes’s own father.

The music, meanwhile, continues with the same uplifting, harmony heavy folk pop that marked the group out to begin with. Despite all the success for their first album, including the single Ho Hey becoming a radio fixture, the band were determined not to be affected by fame, a theme that pops up on recent single Ophelia.

“I think we did our best not to let fame affect us, but I find it fascinating how success often complicates a group,” says Wes.

“For us, it’s been an incredible journey, but also one that has its bumps and requires a good amount of work to keep it all going.

“I think we’re doing a lot better having learned a lot of lessons from all the previous tours, at living on the road and not just surviving.”

The Lumineers first formed when Wes started playing with drummer Jeremiah Fraites, the younger brother of Wes’s best friend Josh Fraites, who had passed away in 2002. The duo began making music as a way to get over their grief, and gigged around New York for years with little luck.

A move to Denver helped, and the duo soon expanded to a trio when they added cellist Neyla Pekarek. Although there have been several changes since those early days in Colorado, when it came to making Cleopatra the band wanted to root themselves back home again, meaning they rented a house in Denver as their base for working on the album.

“I think we felt like it was more important than ever to make a record exactly how we’d dreamed of making one,” adds Wes.

“The first album allowed us about 10 days of recording, while this one we gave ourselves 44 days so we were able to sink our teeth in a bit more and get the sounds in our head on the album.

“We also wanted for it to be in a place that was a bit rough around the edges and rural, and a barn was ideal, except this barn had state of the art acoustics and the Catskill Mountains.”

That’s not the only scenery the Lumineers have been sampling over the years. They’ve found themselves travelling far further afield than they’d ever have expected.

“It seemed that every time we thought we were finished touring a whole new country would invite us to tour,” recalls Wes.

“The last couple were in South America and South Africa. Once we felt like we’d given a show to all those fans, three years had passed.

“We would have loved to have come out with this album two years earlier, but at the same time we felt lucky to keep being asked to new places to play.

“On our piano player’s birthday, back in February 2013, a few of us rented a car and took a hike to Loch Lomond in the early morning. It was beautiful and felt like something out of a movie.”

They’ve also picked up a few famous fans along the way, with US President Barack Obama listing them as a favourite on a Spotify playlist.

“Yes, that was strange,” admits Wes.

“It begins to feel like nothing is surprising and everything is all at once - it was an honour. We’ve got to get him our new album now!”

The Lumineers, Barrowland, tonight, £22.50, 7pm