Two entrepreneurs working out of a small shop tucked into a corner of a low-slung concrete building in Portland’s Bayside neighborhood are building a company they hope will soon go head-to-head with Bose and other giants of the audio electronics industry.

James Demer and Jayson Lobozzo, both longtime residents of the Portland area, have built a prototype boombox that is rugged, waterproof, wireless and Bluetooth-enabled so the music can be controlled from a smartphone. They call it the DemerBox (pronounced DEE-mer).

It’s a “David versus Goliath” situation, Demer said, “but we’re ready for the challenge.”

To date, Demer and Lobozzo have bootstrapped their business, investing their own money and taking time away from their families when they’re not at their day jobs – both work in the television and film industry, Demer as a sound mixer and Lobozzo as a camera operator. They have a small line of credit from Gorham Savings Bank, but Lobozzo estimates the pair have sunk $30,000 of their own money into the business.

Lobozzo, a 43-year-old Cape Elizabeth resident, said the past year and a half has been tough, but the experience has made the company stronger.

“It’s been good because the more tenacious you can be, the better foundation it will set up for you moving forward,” Lobozzo said.

The company, which was incorporated in February 2013, is on the verge of taking its prototype to the next level.

About a month ago, the pair launched a Kickstarter campaign to raise funds to begin manufacturing the DemerBox. The social media fundraising platform, which has its roots in the art and music industries, requires an organization to reach its fundraising goal for the money to be released. The DemerBox campaign deadline is Saturday at 7:43 p.m. As of Tuesday evening, backers had pledged $55,000 of the $60,000 goal.

On Tuesday, the company also got word that it will receive a $25,000 seed grant from the Maine Technology Institute. That’s in addition to a $5,000 TechStart grant the company received from MTI in May.

With the MTI grant and the presumed funds from the Kickstarter campaign, the company will be able to ramp up production for two styles of the DemerBox. The Bang is the size of a lunchbox, has one speaker and will retail for $299. The Big Bang is a bit larger, holds two speakers and will retail for $399.

What sets the DemerBox apart from competitors is that the boomboxes are built inside Pelican cases, which are used to protect high-priced camera equipment and military-grade hardware, among other things. Demer and Lobozzo have thrown a DemerBox off the back of a moving Jeep, frozen it in a block of ice, dropped it from a balcony onto a concrete floor 20 feet below and left it outside in a snowstorm for 24 hours. In all cases, the DemerBox kept cranking out music – although it did need time to thaw out after the ice episode. “And because it’s built using a Pelican case, the boombox doubles as a place to carry things, whether a few beers for a fishing trip or a packed lunch to bring to the worksite.”

“We love this thing,” Lobozzo said. “It’s kind of like a Tonka Truck. We’re hoping it’s a legacy product you could have banging around for years and years and years.”

NATURAL STEP FOR A TINKERER

The launch of DemerBox is a natural culmination for Demer, an inveterate tinkerer.

The 45-year-old Falmouth resident has tried his hand at making athletic clothing, building bicycle frames, and once made a hot tub out of a discarded wine barrel. When his daughter, now 17, went trick-or-treating as Cinderella many years ago, he pulled her around the neighborhood in a giant pumpkin carriage he built out of chicken wire and more than 500 Christmas lights powered by a car battery.

“For me, if I’m not making things I feel like I’m missing something in my life,” Demer said Tuesday while riding a ferry from Martha’s Vineyard, where he was working on a television show. “It’s way more fun for me to build my own thing than to buy it.”

In 2010, Demer decided to build his own set of portable and rugged speakers to bring with him to a movie location in Alaska that was north of the Arctic Circle. He took a Pelican case – which are ubiquitous in the film industry for equipment – cut a few holes in it, screwed in some old speakers he had lying around and built the first DemerBox, which he used as a playback device on the set.

Colleagues soon asked if he could make versions for them. When he got back to Maine, he went to his basement and tinkered with the design. In total, Demer estimates he’s made roughly 30 prototypes by hand, each iteration a slight improvement over the last.

But the DemerBox would have remained another of Demer’s hobbies if Lobozzo hadn’t become involved. The two became friends on a film set in the late 1990s. While Demer said he’s an “ideas guy,” it was Lobozzo who saw the business opportunity and has brought efficiencies to the manufacturing process.

“If Jayson didn’t come along I’d still be building prototypes, but he gets things done,” said Demer, who recently returned from a two-and-a-half-month job in Nicaragua on the set of the next season of the hit TV series “Survivor.” “Jayson is the guy who saw magic in the DemerBox and said, ‘Let’s bring this to the world.’ ”

They rented a manufacturing space on Preble Street in the Bayside neighborhood in August 2013.

Based on an earlier prototype, the pair built 50 DemerBoxes and quickly found buyers for them, including colleagues in the film and television industry. So they made 150 more. Same result. They were soon sold out.

“It’s a visceral product. People see it and say, ‘Oh my God! That’s so cool. I want one. … What is it?’ ” Lobozzo said. “And I don’t think that’s a bad place to be.”

CREATING A FOLLOWING

The product has garnered some big fans.

Chris Olesen, the East Coast sales and new-business development manager at Pelican, brings his two DemerBoxes to every trade show he attends. They bring a lot of clients to Pelican’s booth. He also brings them to sales meetings.

“You’re trying to sell asset protection, but to show them the different solutions that people come up with I can show them the DemerBox as a model and it gets them intrigued,” Olesen said. “If a meeting gets slow I can whip that out and they get engaged.”

The Torrance, California-based company has promoted DemerBox’s Kickstarter campaign on its Facebook page and assigned the company its own SKU code, so the Pelican cases arrive at the Bayside shop with the cover already removed and the case ready to be retrofitted.

Based on his 15 years as an audio professional, Demer believes the DemerBox offers sound quality second to none. But don’t take his word for it.

By virtue of his job, many of Demer’s early customers are fellow sound engineers. One big fan is Kamal Humphrey, lead audio supervisor on “American Idol,” who uses a DemerBox to monitor audio on the show’s set, Demer said.

“Being on the road half the year for work, the DemerBox provides portable sound reproduction with a nice round bottom in a small rugged case that packs a punch,” Humphrey says in a testimonial published on DemerBox’s website.

Demer and Lobozzo are hoping to manufacture as much of the DemerBox in Maine as they can. The circuit board is manufactured by Alternative Manufacturing Inc. in Winthrop. The pair have spent money to get 3D prototypes that will allow them to begin injection molding, hopefully at a plant in New England. All assembly and testing will stay in Portland.

“Jayson and I love Portland and want to be here with our families,” he said. “We’d love to have some employees and be contributing to the local and state economies, and be making something everyone in Maine could be proud to call a Maine product.”