Finn Wolfhard, a 14-year-old actor with a shaggy haircut and a baby face, was perusing the aisles of Rough Trade NYC, a far-from-extinct music store in Williamsburg, Brooklyn. Flipping through stacks of vinyl, he stopped every so often to comment on a record.

“Oh, wow, they have ‘Pinkerton,’” he said of Weezer’s second album, which came out in 1996 and received mixed reviews. “This is so much better than their first one.”

Turns out, Finn is something of a pop-music fanatic, and has been ever since he was 6 and his mother introduced him to the Beatles (“Actually kind of late,” he said). He took up the bass guitar at 7, and now plays in a garage-rock quartet called Calpurnia, named after Atticus Finch’s housekeeper in “To Kill a Mockingbird.”

“Honestly, if acting never worked out, I would have done music,” said Finn, who was flanked by his father, Eric Wolfhard, a researcher on aboriginal land claims, and his publicist, Michael Geiser.