From their debut release “Parachute” in 1995 to the band’s latest album, “Keep It Together,” Guster is an ever-changing group that keeps fans guessing about where they’ll go next in terms of sound.

“I think every record is different,” said Adam Gardner, Guster’s guitarist/vocalist. “I think we just sort of go for what we’re feeling.”

With at least two years between each album, the way Gardner and band mates Ryan Miller, guitar/vocals, and percussionist Brian Rosenworcel feel can vary quite a bit.

Fans at Eastern will catch a glimpse of the band’s newest evolution during tonight’s concert at 7 p.m. at Lantz Arena. Guster will play many of the songs fans know and can sing along to, as well as some tracks off of their newest, unreleased and yet-to-be-named album.

The upcoming album reflects classic, vintage music straight out of the ’60s and ’70s, with influences like the Beatles, Led Zeppelin and even Pink Floyd, according to Gardner.

“We wear our influences more on our sleeve,” Gardner said. “You can hear a lot of early Kinks and Beach Boys.”

A classic rock album illustrates a steady progression of change, from their folksy debut album, “Parachute.”

“We keep learning and growing as writers from record to record,” Gardner said.

The band’s signature sounds have evolved as well, from mostly hand percussion and acoustic guitar to electric guitar, drums, keyboard and bass, which has been made possible with the addition of a fourth band member, Joe Pisapia on bass/keyboard/guitar, who joined two years ago.

The new album is the band’s first as a foursome, which also makes it possible for Guster to do more with live shows like this one and pull off a sound that just wasn’t possible with only three people, Gardner said.

Even with the evolution of the music, the band’s intricate guitar parts and careful arrangement of songs make the band stand out from others. Gardner explained that it’s hard to be compared to other bands.

“Offer something unique,” Gardner said. “Otherwise, don’t bother.”

Despite the band’s growing popularity with a largely college-aged audience, they play a variety of venues, from parking lots to amphitheatres, and also colleges, bringing them back to their roots.

Gardner, Miller and Rosenworcel met at their freshman orientation at Tufts University in Massachusetts, and started talking about their interests in music, Gardner said. When they got together as a band, they settled on the name Gus.

The name didn’t require a lot of thought, because they didn’t know they would go further than college, he added.

After the band learned that the music business wasn’t big enough for more than one act called Gus, they changed their name to Guster.

Guster progressed outside of their college atmosphere, even without an extensive amount of formal training, as the band members proclaim themselves mostly self-taught. By graduation time, they had enough money to buy a van, and they hit the road with their music, Gardner said.

“Everything progressed nicely so we were comfortable the whole way,” Gardner said.

“There was never an enormous break.”

There were plenty of highlights along the way though, including the first time they played their own headliner and sold out, the first time they played on national television and most recently, the first time they heard a 100-piece orchestra play their music at the Boston Pops Symphony, Gardner said.

Touring is something the band loves to do, visiting places they’ve been and people they’ve met, and meeting new people as well, he said.

Before the show, the band enjoys a little solo time, to focus on what’s ahead for the night. As far as pre-concert rituals go, “We don’t put on ‘Eye of the Tiger’ and start high-fiving or anything,” Gardner said.

Most of all, Guster plays to audiences that don’t feel inferior to them, which makes their live shows a big hit.

“We’re very normal,” Gardner said. “We don’t put up the rock ‘n’ roll wall between band and audience. We’re in it together.”

The new songs audience members will hear at the concert are expected to hit stores in album form this spring, and Gardner said fans won’t be disappointed.

“Every new album is our best,” he said. “We’re only getting better.”