In the Edgartown Triangle there is a store with boxes of compact discs labeled “$1” out front, crates of used CDs inside, and a sizeable collection of new and used vinyl. Aboveground Records is adapting to the 21st century.

The heart of the business is Vineyard-born Mike Barnes. At 36, he has owned Aboveground for 16 years. The store began before the mp3 existed and has seen what that technology has done to the music industry.

“We’ve lost the casual music fan years ago, so now it’s a much different pace than it once was,” said Mr. Barnes, standing behind one of two counters in his poster-plastered store. “As we started this interview I was actually busy, and for two hours before that I hadn’t seen anyone.”

In the late 90s Aboveground Records did well enough that Mr. Barnes was able to expand to the space next door to the original, one-room store. He took out the wall separating the two spaces, creating one big room. He bought both spaces with the profits and was even able to go traveling, leaving a staff to manage and run the store.

But the pace of the operation has shifted. There are no longer the large mobs that would continuously flow through the store in past summers. Aboveground has a humbler and smaller business model than it did when people were looking for new discs of Top 40 music.

“[The new model is] used stuff that I can sell cheaper than iTunes,” said Mr. Barnes. “That’s the one place where we can have the copy of the Eagles Greatest Hits for $6.99 used, rather than having to buy it for $12 on iTunes.”

The foot traffic in the store is less these days, but the new business model is viable because of the cheap prices he pays for used CDs. When Mr. Barnes buys a used disc as part of a collection and sells it for $6, the profits are similar to what music stores used to make buying a new disc from a record label for, say, $13 and then sold at $16.

“The register at the end of the day looks like a lot less but hopefully the profits are still the same. So everybody is getting music for cheaper than they ever got it before.

“That’s the nice thing of going more used than new — it’s a much more reasonable price range to be working in for the consumer and for me as the retailer,” he said.

The Aboveground Records T-shirt also has done a lot for the business, said Mr. Barnes. While he emphasizes he is decidedly “not a clothing person,” the shirts sporting the a-with-an-asterisk logo have brought in a lot of revenue. They were less than a side note to the business for many years — until the New York Times printed a story about Martha’s Vineyard T-shirts. In its Sunday Magazine, the Times wrote that the Black Dog T-shirt was not, in fact, the T-shirt that Islanders would wear; the Aboveground T-shirt was the shirt of choice. From then on the a-with-an-asterisk T-shirts became a large moneymaker and advertiser for the business. They are also a motivational factor for Mr. Barnes.

“I always say I can’t close because all the people with our logo as a bumper sticker on their car, they’d have to take them off. And all the shirts ­— it’d be like, ‘Remember when that place was here?’ It’s one of the things that keeps me going,” he said.

Mr. Barnes lives with his wife, Alicia Barnes, and their 10-year-old sons, Henry and Ian. They have been brothers since Mike and Alicia got married seven years ago. Mr. Barnes has started them on playing several different instruments. And of course they both have iPods.

“My son, when I was filling up his iPod, wanted Black Sabbath and some Lady Gaga,” said Mr. Barnes.

He said that the boys often have pop music radio stations playing in the car. “They normally have, like, Fun 107 or Jammin 945 in the car and we listen to it for like an hour and then it’s like, ‘Okay! We’re going to switch to something else now!’

“But I’m actually more up on popular music than I ever have been,” he said, “because of my kids taking an active role, and I’m just excited that they like something. Whatever it is, whether I like it or not, just being passionate about music is exciting, just having your favorites, the things that get you.”

Some of Mr. Barnes’ favorite bands include The Archers of Loaf and the Island band Kahoots. He plays music as well but does not consider himself a musician simply because he doesn’t think it would be fun to listen to what he plays. But it is fun to play, he said.

Mr. Barnes has no regrets about staying on the Island over the years.

“There’s not much I like more than traveling, but every time, no matter what time of year, I’d go on the top of the boat coming in to Vineyard Haven harbor. And it’s like ‘I’m home,’” he said. “I have no problem leaving for months at a time and I don’t miss the Island, it’s not like the security of the Island is what keeps me here. I like the fact that you can walk five minutes in any direction and find something beautiful.”

His goal for the future is to retire to a mostly off-the-grid house which he wants to build on land his family owns on Chappaquiddick. In his imagination, it has solar panels and chickens. When his sons are old enough to take care of themselves, he hopes to travel with his wife.

A girl walked in to the store near the end of the interview. She asked if Mr. Barnes has Joni Mitchell’s Blue on vinyl.

“Yeah, we don’t have any on vinyl right now,” said Mr. Barnes quickly relaying his categorical knowledge of his store’s holdings.

“I’ve been looking everywhere,” said the exasperated customer.

“It’s funny, a year ago I had six copies and I think I was selling them for a dollar or three dollars, and now I get them in and they’re gone that day,” he said. “It’s like, wow, people realize how good of a record it is.”

She decided to buy another Joni Mitchell vinyl album.

“I’m sorry,” she said, perhaps thinking she had distracted Mr. Barnes from something.

“Oh, no, don’t apologize,” he said. “You want to buy a record from me!”

When the store was once again empty, he said, “There’s people who give really nice compliments to the store sometimes, like really genuine, ‘We’re really glad you’re here, we love it.’ It’s not the people spending a lot of money, it’s the real genuine ‘We like your store’ is what keeps it going. That’s the neat part.”

The article has been corrected from the original to correct spelling.