The Thomas Edison National Historical Park in New Jersey hosts an online library of salvaged recordings from the original dolls. Recently, it added recordings from Robin and Joan Rolfs, who were in possession of two of the dolls but were unable to play the recordings. They feared that, after all these years, the steel phonograph needle might damage the grooves on the cylinder that plays back the sound.

Luckily, some cool technology solved that problem. The Lawrence Berkeley National Laboratory and the Library of Congress developed an optical scanning method called IRENE-3D. According to the National Park Service, “The IRENE-3D system creates a digital model of the surface of a phonograph record. With the digital model, image analysis methods are used to reproduce the audio stored on the record.”

So as long as the grooves still exist, they can be modeled, and a computer can recreate the sounds you would have heard if a needle were to move through them. The Northeast Document Conservation Center in Massachusetts is currently leading the effort to make the IRENE technology more widely used.

Technology aside, the recordings are still quite unsettling. Good luck sleeping tonight.

📬 Sign up for the Daily Brief

Our free, fast, and fun briefing on the global economy, delivered every weekday morning.