Two dueling projectors splashed trippy images on sheets draped behind the stage at The Barley Pub in Dover on Nov. 17. At one projector, a volunteer held a blue rubber bathmat under the light, casting an image of large azure bubbles on the wall behind the band. She continually folded and rotated the mat, making the bubbles appear to pulsate and undulate. At the other projector, another volunteer manipulated a plastic bag full of multi-colored fluids to produce a liquid lightshow on the adjacent wall. The two projected images overlapped in the middle, resulting in a strangely visceral effect, like bodily fluids coursing between throbbing internal organs.

It felt like a hazy flashback to a Jefferson Airplane concert in San Francisco, circa 1967. But the band onstage was Mmoss, a Dover-based quartet of 20-somethings featuring Doug Tuttle on electric guitar, Rachel Neveu on organ and flute, Justin DeArmitt on bass and Brian Levin on drums.

The group offered a psychedelic stew of retro rock, often with harmonized vocals and strong organ presence from Neveu. Even their physical appearance harkened back to the late ’60s, with Tuttle sporting a mustache, Levin wearing a bushy beard and DeArmitt flaring thick sideburns and wavy hair.

And yet it would be an oversimplification to call Mmoss a derivative band. They have aptly been described as “garage folk” and “garage prog,” mixing elements of post-punk, and shoegaze into their droning, psychedelic sound. During a cigarette break outside the pub, the band members struggled to qualify their style.

“I’m personally afraid of the term ‘psych,’ because it’s very misleading,” Levin said.

“It’s very popular to throw that term around,” Tuttle agreed.

For one thing, the word “psychedelic” raises hippie connotations, while this group is solidly ensconced in the modern indie rock movement. “Maybe our parents are hippies and we’re the product of that,” Neveu offered.

DeArmitt provided a more concise assessment of the music. “I would describe it as enjoyable,” he said, eliciting laughter from his band mates.

Tuttle and Neveu started Mmoss in 2007. They shared a mutual fondness for Syd Barrett-era Pink Floyd, although Neveu’s favorite band is Crosby Stills Nash and Young. They met DeArmitt while he was working at Bull Moose in Portsmouth.

“He’d always compliment whatever CDs we were buying. So then one day we were like, ‘Let’s start a band,’” Neveu said.

“We actually asked him to be in the band before we even knew he played an instrument,” Tuttle joked.

They later brought Levin onboard and soon recorded their debut album, “i,” offering it exclusively on cassette tape. They initially produced just 100 copies of the tape, and California-based indie label Burger Records churned out another 250. The album is now sold out (there might be a single copy left at Odyssey & Oracle in Portsmouth), and Burger will soon produce another batch of 250.

The entire album is also downloadable online, and Burger plans to release a vinyl printing early next year. Wild Honey Records in Italy is also producing “i” on vinyl, but the album is still not available on CD. The old-school recording formats reflect a general nostalgia for lo-fi cassettes and vinyl records, a modest backlash against the digital iPod age. Even as Sony announced last month that it would stop manufacturing cassette Walkmans, tapes are making a bit of a comeback.

“The cassette’s just kind of a quick, easy way to put it out,” Tuttle said. “There seems to be some kind of cassette revival thing going on, so people are willing to do it.”

Tapes also demonstrate the same sort of DIY mentality that made the makeshift lightshow at The Barley Pub so endearing. Without a budget for mass marketing, Mmoss has built a healthy following through sheer word of mouth. “We like doing it ourselves. Why not? Why have someone else do it?” Neveu said.

Mmoss embarked on a brief tour of California in October and recently played at Deep Heaven Now, a small psychedelic rock festival in Boston. Two nights after their gig in Dover, they performed at the Memorial Union Building at the University of New Hampshire in Durham. They’re planning a nationwide tour for next March, including a stop at the South by Southwest festival in Austin, Texas.

Mmoss has already won over Seacoast audiences, as evidenced by the dense Schlitz-schwilling crowd at The Barley Pub on a Wednesday night. The show began with fellow New Hampshire band The Migs, with whom Neveu sat in on organ. The Migs have a similarly fuzzy garage rock sound, channeling acts of yore like 13th Floor Elevators, Quicksilver Messenger Service and Love. They implemented the same lightshow (with DeArmitt operating one of the projectors) and prepped the crowd with a raw and boisterous performance.

Mmoss showcased a slightly more polished delivery and progressive sound, blending into the lightshow like a sonic kaleidoscope. Their style calls to mind early Floyd albums like “Piper at the Gates of Dawn” and “A Saucerful of Secrets,” with a folk sensibility akin to the Incredible String Band and four-way harmonies that echo CSNY.

Mmoss is also prone to delightfully rollicking jams, as demonstrated in a raucous flute solo by Neveu at the end of the first set. Usually offering soft melodic touches on flute, she let loose before the break with an unrestrained, Ian Anderson-esque attack, drawing whoops of approval from the crowd.

While the show would not have seemed out of place at a late-’60s acid test party, the vibe was still energetic in 2010. And, in an age when cassette tapes increasingly seem like relics from a past epoch, the band’s DIY approach feels fresh. Mmoss takes listeners on a virtual tour of a bygone musical era, and all without leaving the pub.

For more on Mmoss, visit www.myspace.com/themmoss or www.mmoss.bandcamp.com.