Instead of browsing songs listed alphabetically or by genre, listeners on the Web site Radiooooo explore playlists organized by decade and by geography. Photograph by Stan Wayman / Time Life Pictures / Getty

In 2012, Benjamin Moreau, an artist and d.j., was test-driving his car-collector father’s most recent acquisition, a white 1966 Renault Caravelle, in the French Riviera. “As we drove along this road, lost in time, my fingers came across the splendid old radio on the exquisite wooden dashboard,” he recalled. When Moreau switched it on, the speakers belched “a wave of awful commercial music,” he said, “instantly bursting the time bubble we were so happily swimming in.” The moment led to an idea: what if you could organize music, not based on genre or complex algorithms but instead as a part of time and space? What if, instead of scrolling through artists and songs arranged alphabetically, you could explore them historically and geographically?

He brought the concept to his friend Raphaël Hamburger, a music producer and soundtrack supervisor who had amassed a vast collection of music from all over the world. You pick a country on a world map, select a decade in the twentieth century or the aughts (or listen to contemporary music via a “Now” option), and enjoy a curated playlist of crowdsourced songs from that time and place.

They called their idea and company Radiooooo—the five o’s represent the five continental landmasses, all of which you can hear music from, though Antarctica’s stations contain mostly whale songs. (So as to avoid confusion, they bought all the domains from radiooo.com to radioooooooooooooooooooo.com.) In 2013, they secured funding and were able to launch the site. By this time they had partnered with Anne-Claire Troubat, an attorney specializing in international business, who left her job at an investment firm to become C.E.O. To get their time machine started, Moreau and Hamburger needed a community of contributors. They took advantage of one of the Internet’s great human resources, the obsessively specialized music nerd, to endow the collection.

Radiooooo employs curators who spend hours every day combing through hundreds of submissions from almost thirty thousand contributors, from all over the world (Troubat refers to them as “treasure hunters”). The curators make sure the audio files are high quality, and judge whether or not the song fits the Radiooooo aesthetic, which can be difficult to define. For Moreau, the decisions about which music to include are instinctive, and “the music is only selected based on how we feel when we start listening to a track. The ability of a song to touch us instantaneously, in a completely subjective way. I would almost say in a naive way . . . We are not trying to apply ethno-musical criteria. We are keeping what we believe are true musical treasures.” Troubat told me that the strength of the editorial line leaves lots of good music, about ninety per cent of submissions, out of the collection.

The result is that Radiooooo listeners, of whom there are now over a hundred and seventy thousand, have access to music from inveterate collectors of Mandopop, Afrobeat, Italo disco, Yé-yé, and many other genres. Attention to detail is apparent in the collection, but elsewhere, too. On loading Radiooooo’s site, you are presented with a map of the world that was hand-drawn by Moreau and his partner Noemi Ferst, an illustrator and Radiooooo’s artistic director, using a quill pen and ink. Even the user experience is pleasantly calculated: click on a country, select a decade, as well as a mood: slow, fast, or weird, for “those eager to take the trip a little further.” Afterward, you can enjoy song after song, as though you were listening to the best radio station in eighties Berlin, sixties Bangkok, or seventies Beirut. In Taxi Mode you can cobble together your own “musical road trip” by combining any number of countries and decades, for example Colombia, Ethiopia, and Sweden in the fifties, sixties and seventies. This feature allows you to experiment with space-time combinations—like a time-travelling d.j. in pursuit of the universe’s vibe.

And, like any great d.j., Radiooooo inspires a compulsive urge to find out what’s playing. I found myself clicking back and forth between browser tabs to capture the name of the Peruvian rock group from the sixties, or diving across the kitchen, spatula in hand, to jot down a song from the Shanghai jazz scene in the nineteen-twenties. I also found Radiooooo pleasantly limiting: you can’t scroll through an endless catalogue and pick the artist or song that you want to listen to. You aren’t allowed to skip songs you don’t like; instead, you’re forced to choose another decade or country. For Troubat, the choice that services like Spotify and Pandora provides is ultimately an illusion, in which abundance is actually constraining, “I think right now on the Internet there are so many choices that you end up listening to always the same things, like you have your habits and if you listen to Spotify the algorithms will always get you back to what you know,” she said.

It is rare to find a tech company so steeped in nostalgia, yet that is precisely what makes Radiooooo not only charming, and somehow quintessentially French, but also remarkably effective. The developers are relying not on algorithms or crowdsourcing or big data, but on the mercurial dictates of taste. An algorithm can never account for the intangible qualities of music the way a radio d.j. or older sibling might. Radiooooo fills this role elegantly. It takes advantage of one of the best things about the Internet, the ability of people from all over the world to contribute to a common cause, and rejects one of the worst, the dispiriting monotony of automated algorithmic curation.