Anticipating Pope Francis’ celebration of Mass on Saturday, the Cathedral Basilica of Saints Peter and Paul in Philadelphia installed speakers made by Brunswick-based Terra Speakers to upgrade its sound system.

The 15-year-old speaker manufacturer is not well known in Maine, primarily because it’s not a retailer – you can’t buy its speakers off a shelf at Best Buy or Target. But its network of custom dealers has installed Terra’s hand-built indoor and outdoor speakers across the country in high-end homes and commercial properties, primarily faith-based properties, according to James Banfield, a company co-founder.

Pope Francis' words will be amplified by Maine-made Terra Speakers at the Cathedral Basilica of Saints Peter and Paul in Philadelphia.

A custom dealer installed nearly three dozen of Terra’s speakers throughout the Philadelpia basilica a few weeks ago. The speakers are designed to be inconspicous and blend in with the church’s architecture, Banfield said.

The dealer who did the work has been a longtime customer of Terra and in the last 15 years has used the company’s speakers in roughly 2,500 jobs, primarily in the New York City area.

“It is sort of surreal to be involved in this historic event in even this small way,” Banfield said. “Our speakers have ended up in the hands of celebrities we admire as well as in restaurants we love. To have them be a part of this spectacle has been really incredible.”

Banfield and his business partner, Chris Perron, founded Terra Speakers in 2000 in Perron’s father’s garage in Sabattus. They had both previously worked for New England Audio Resource, better known as NEAR and still based in Gardiner, but they left the company after it outsourced its speaker manufacturing overseas. They decided to start manufacturing their own speakers when a former NEAR customer contacted them about making some custom speakers.

Banfield estimates his team of five full-time employees in Brunswick, including himself and Perron, manufactures between 5,000 and 6,000 speakers a year.

“We hand-make the drivers in Maine, as well as put them in cabinets and do a lot of the soup to nuts,” Banfield said. “That’s one of our benefits – we can control the quality.”

Terra’s speakers are installed in more than 100 churches and synagogoues in the New York metro area, so the installation in Philadelphia’s basilica is a typical job. Other high-profile customers include the New York Police Department, West Point, Pixar and Fordham University.

Terra Speakers isn’t the only Maine manufacturer involved in the pope’s visit to the United States. Auburn-based furniture maker Thos. Moser will provide custom-made armchairs for the pope and four cardinals during a stop at Independence Hall on Saturday and then again when the Pope Francis says goodbye at the airport.