In 1922, Italian immigrant Carlo Petosa founded the Petosa Accordion Company in the basement of his home. It joined the scores of similar stores and schools popping up all over the country. “Some towns had as many as four accordion schools in a couple of blocks,” said Grauman, who also added that by the 1950s the accordion was likely one of the most studied instruments in the country.

By 1938, the AAA was founded in New York, and its first president, Pietro Deiro, became fondly known as the “daddy of the accordion.” The group’s initial goal was to show the public that the instrument was as serious as any other. A year later, it succeeded by helping to facilitate the first-ever accordion performance at Carnegie Hall.

The Petosa Accordion Company survives till today, as the only US-owned-and-operated accordion manufacturer around. Many of its rivals started to die out as rock and roll came to prominence in the ‘60s. Acts like The Beatles popularized the guitar-drums-vocals setup that remained the pop-culture standard for decades to come, though ironically, according to Grauman, both Elvis and John Lennon played the accordion before beginning the guitar.

Petosa’s clientele has transitioned over the decades from early-century players who were trained in classical accordion from a young age, to lone solo accordionists pursuing it as a hobby, to, now, players affiliated with musical groups. Nirvana’s Novoselic just stopped in the store a few months ago. Owner Joseph M. Petosa said the age of customers has also changed, with 60 percent now under the age of 30, whereas 10 years ago it was only 10 percent. And over the last three years, “we’re almost selling more accordions then we’re making,” Petosa said. The company has responded to demand by introducing a second, cheaper line of instruments.

Shenandoah Davis is one of the recent musicians to join the accordion world. The 28-year-old grew up playing classical piano and studied opera performance in college. She discovered the accordion six years ago, and after only a few days playing it, was swept up into a country-rock band called Jack Wilson and the Wife Stealers.

Davis believes the rise in popularity of the accordion has a lot to do with today’s anything-goes music industry, enabled by the Internet. “I think in general people have felt a little bit braver about what kind of music they’re creating,” she said, “and more interested in stepping outside of the realm of what pop or rock music is supposed to sound like.”

There’s also the fact that the instrument is in line with the so-called “retromania” of the new millennium. While the accordion is, as Petrosa says, “one of the only instruments that’s basically found in every style of music throughout the world,” it’s largely associated with European and American folk music. Which, of course, is cool again, as seen in the popularity of acts like Mumford & Sons and Of Monsters and Men.