It’s a tedious process, making bespoke variants at Erika. For swirled vinyl, which when finished resembles tie-dye, each record takes a few minutes to manufacture. On this day, employee Guadalupe Herrera was setting a puck in what looked like a big waffle maker. But instead of batter, it was a pliable polymer disc; he sprinkled it with glitter, added another puck, pulled the top down and squished the vinyl to imprint microscopic grooves containing sound waves onto it. Another employee, Denise Hernandez, was inserting, by hand, newly minted “Madvillainy” records into each jacket.

Read Mr. Roberts LA Times story on the vinyl demand in Southern California: As superstars cash in on vinyl LP boom, small labels and manufacturers struggle to meet demand